ABSTRACT
The beamline optics and endstations at branch B of the Versatile Soft X-ray (VerSoX) beamline B07 at Diamond Light Source are described. B07-B provides medium-flux X-rays in the range 45-2200â eV from a bending magnet source, giving access to local electronic structure for atoms of all elements from Li to Y. It has an endstation for high-throughput X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine-structure (NEXAFS) measurements under ultrahigh-vacuum (UHV) conditions. B07-B has a second endstation dedicated to NEXAFS at pressures from UHV to ambient pressure (1â atm). The combination of these endstations permits studies of a wide range of interfaces and materials. The beamline and endstation designs are discussed in detail, as well as their performance and the commissioning process.
ABSTRACT
BACKGROUND: Failure of the glomerular filtration barrier, primarily by loss of slit diaphragm architecture, underlies nephrotic syndrome in minimal change disease. The etiology remains unknown. The efficacy of B cell-targeted therapies in some patients, together with the known proteinuric effect of anti-nephrin antibodies in rodent models, prompted us to hypothesize that nephrin autoantibodies may be present in patients with minimal change disease. METHODS: We evaluated sera from patients with minimal change disease, enrolled in the Nephrotic Syndrome Study Network (NEPTUNE) cohort and from our own institutions, for circulating nephrin autoantibodies by indirect ELISA and by immunoprecipitation of full-length nephrin from human glomerular extract or a recombinant purified extracellular domain of human nephrin. We also evaluated renal biopsies from our institutions for podocyte-associated punctate IgG colocalizing with nephrin by immunofluorescence. RESULTS: In two independent patient cohorts, we identified circulating nephrin autoantibodies during active disease that were significantly reduced or absent during treatment response in a subset of patients with minimal change disease. We correlated the presence of these autoantibodies with podocyte-associated punctate IgG in renal biopsies from our institutions. We also identified a patient with steroid-dependent childhood minimal change disease that progressed to end stage kidney disease; she developed a massive post-transplant recurrence of proteinuria that was associated with high pretransplant circulating nephrin autoantibodies. CONCLUSIONS: Our discovery of nephrin autoantibodies in a subset of adults and children with minimal change disease aligns with published animal studies and provides further support for an autoimmune etiology. We propose a new molecular classification of nephrin autoantibody minimal change disease to serve as a framework for instigation of precision therapeutics for these patients.
Subject(s)
Autoantibodies/blood , Membrane Proteins/immunology , Nephrosis, Lipoid/blood , Nephrosis, Lipoid/etiology , Adult , Child , Child, Preschool , Cohort Studies , Female , Humans , Male , Nephrosis, Lipoid/pathology , Podocytes/pathologyABSTRACT
PURPOSE: Imaging characteristics in bladder cancer (BC), such as hydronephrosis, are predictive of ≥ pT3 disease at time of radical cystectomy (RC). The predictive capacity of other findings, such as perivesical stranding (PS), remains unclear. We investigated whether PS was associated with ≥ pT3 BC in patients who did not receive neoadjuvant chemotherapy (NAC). METHODS: We identified 433 patients with BC who underwent RC from 2003 to 2018 of which 128 did not receive NAC. Evidence of PS on pre-TURBT imaging was determined by radiologist review and a stranding grading system was created. Factors associated with PS and hydronephrosis were identified. Multivariable logistic regressions evaluated PS and hydronephrosis as predictors for ≥ pT3 BC. RESULTS: Of the 128 patients who did not receive NAC, 48 (38%) had pT3 and 12 (9%) had pT4 BC. 125 (98%) patients had CT and three (2%) had MRI. PS and hydronephrosis on imaging were identified in 19 (15%) and 45 (35%) patients. PS was not associated with imaging type (p = 0.38), BMI (p = 0.18), or pathologic T stage (p = 0.24). Hydronephrosis was more frequently associated with higher pathologic T stage (p = 0.034). Multivariable analysis demonstrated that PS was not predictive of ≥ pT3 BC (p = 0.457), while hydronephrosis was positively associated (p = 0.003). Stratification by grade of stranding did not improve the predictive capacity of PS (p = 0.667). CONCLUSION: While hydronephrosis is an indicator of higher stage BC, PS failed to be a reliable predictor of ≥ pT3 stage. These observations should give pause in using PS on imaging to guide decisions until further investigations can be explored.
Subject(s)
Cystectomy , Magnetic Resonance Imaging , Tomography, X-Ray Computed , Urinary Bladder Neoplasms/diagnostic imaging , Urinary Bladder Neoplasms/pathology , Aged , Humans , Hydronephrosis/diagnostic imaging , Hydronephrosis/etiology , Middle Aged , Neoplasm Staging , Predictive Value of Tests , Preoperative Period , Retrospective Studies , Urinary Bladder Neoplasms/complications , Urinary Bladder Neoplasms/surgeryABSTRACT
Among the major challenges in the development of biopharmaceuticals are structural heterogeneity and aggregation. The development of a successful therapeutic monoclonal antibody (mAb) requires both a highly active and also stable molecule. Whilst a range of experimental (biophysical) approaches exist to track changes in stability of proteins, routine prediction of stability remains challenging. The fluorescence red edge excitation shift (REES) phenomenon is sensitive to a range of changes in protein structure. Based on recent work, we have found that quantifying the REES effect is extremely sensitive to changes in protein conformational state and dynamics. Given the extreme sensitivity, potentially this tool could provide a 'fingerprint' of the structure and stability of a protein. Such a tool would be useful in the discovery and development of biopharamceuticals and so we have explored our hypothesis with a panel of therapeutic mAbs. We demonstrate that the quantified REES data show remarkable sensitivity, being able to discern between structurally identical antibodies and showing sensitivity to unfolding and aggregation. The approach works across a broad concentration range (µg-mg/ml) and is highly consistent. We show that the approach can be applied alongside traditional characterisation testing within the context of a forced degradation study (FDS). Most importantly, we demonstrate the approach is able to predict the stability of mAbs both in the short (hours), medium (days) and long-term (months). The quantified REES data will find immediate use in the biopharmaceutical industry in quality assurance, formulation and development. The approach benefits from low technical complexity, is rapid and uses instrumentation which exists in most biochemistry laboratories without modification.
Subject(s)
Antibodies, Monoclonal/chemistry , Protein Conformation , Protein Stability , Spectrometry, FluorescenceABSTRACT
The ambient-pressure endstation and branchline of the Versatile Soft X-ray (VerSoX) beamline B07 at Diamond Light Source serves a very diverse user community studying heterogeneous catalysts, pharmaceuticals and biomaterials under realistic conditions, liquids and ices, and novel electronic, photonic and battery materials. The instrument facilitates studies of the near-surface chemical composition, electronic and geometric structure of a variety of samples using X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine-structure (NEXAFS) spectroscopy in the photon energy range from 170â eV to 2800â eV. The beamline provides a resolving power hν/Δ(hν) > 5000 at a photon flux > 1010â photonsâ s-1 over most of its energy range. By operating the optical elements in a low-pressure oxygen atmosphere, carbon contamination can be almost completely eliminated, which makes the beamline particularly suitable for carbon K-edge NEXAFS. The endstation can be operated at pressures up to 100â mbar, whereby XPS can be routinely performed up to 30â mbar. A selection of typical data demonstrates the capability of the instrument to analyse details of the surface composition of solid samples under ambient-pressure conditions using XPS and NEXAFS. In addition, it offers a convenient way of analysing the gas phase through X-ray absorption spectroscopy. Short XPS spectra can be measured at a time scale of tens of seconds. The shortest data acquisition times for NEXAFS are around 0.5â s per data point.
ABSTRACT
The discovery of novel catalytic materials is predicated on understanding contemporary synthetic processes. With this fundamental knowledge in place it becomes possible to modify the final material with subtle changes to the synthesis process. In this vein, hierarchical materials, formed by the addition of a mesoporogen within the hydrothermal synthesis, have attracted a significant amount of attention due to their catalytic benefits over analogous microporous species. In this work we monitor the hydrothermal synthesis in situ of a hierarchical and a microporous aluminophosphate, for the first time, combining total scattering and pairwise distribution function data. In doing so we observe the local formation of the species, and the longer range crystallisation processes concurrently.
Subject(s)
Glomerulosclerosis, Focal Segmental , Nephrotic Syndrome , Podocytes , Humans , ProteinuriaABSTRACT
Tripartite ATP-independent periplasmic (TRAP) transporters are secondary transporters that have evolved an obligate dependence on a substrate-binding protein (SBP) to confer unidirectional transport. Different members of the DctP family of TRAP SBPs have binding sites that recognize a diverse range of organic acid ligands but appear to only share a common electrostatic interaction between a conserved arginine and a carboxylate group in the ligand. We investigated the significance of this interaction using the sialic acid-specific SBP, SiaP, from the Haemophilus influenzae virulence-related SiaPQM TRAP transporter. Using in vitro, in vivo, and structural methods applied to SiaP, we demonstrate that the coordination of the acidic ligand moiety of sialic acid by the conserved arginine (Arg-147) is essential for the function of the transporter as a high affinity scavenging system. However, at high substrate concentrations, the transporter can function in the absence of Arg-147 suggesting that this bi-molecular interaction is not involved in further stages of the transport cycle. As well as being required for high affinity binding, we also demonstrate that the Arg-147 is a strong selectivity filter for carboxylate-containing substrates in TRAP transporters by engineering the SBP to recognize a non-carboxylate-containing substrate, sialylamide, through water-mediated interactions. Together, these data provide biochemical and structural support that TRAP transporters function predominantly as high affinity transporters for carboxylate-containing substrates.
Subject(s)
Arginine/metabolism , Bacterial Proteins/metabolism , Membrane Transport Proteins/metabolism , Adenosine Triphosphate/metabolism , Amino Acid Substitution , Arginine/chemistry , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Binding Sites/genetics , Crystallography, X-Ray , Genes, Bacterial , Haemophilus influenzae/genetics , Haemophilus influenzae/metabolism , Kinetics , Ligands , Membrane Transport Proteins/chemistry , Membrane Transport Proteins/genetics , Models, Molecular , Mutagenesis, Site-Directed , N-Acetylneuraminic Acid/metabolism , Protein Conformation , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolismABSTRACT
Water-soluble trialkylphosphines such as tris(carboxyethyl)phosphine (TCEP) and trishydroxypropyl phosphine (THPP) are effective agents for reducing disulfide bonds in proteins and are increasingly becoming the reagents of choice for bioconjugation strategies that modify cysteine (thiol containing) amino acids. These reducing agents are often considered as being chemically compatible with Michael acceptors such as maleimides and, as such, are often not removed prior to performing protein conjugation reactions. Here, we demonstrate the rapid and irreversible reaction of both TCEP and THPP with derivatives of the commonly employed thiol alkylating groups, maleimide and vinyl sulfone. Mechanistic investigations revealed distinct differences between the reactions of TCEP and THPP with maleimide, leading to the production of either nonproductive ylenes or succidimidyl derivatives, respectively. Importantly, we also demonstrate the incorporation of nonproductive ylenes formed between maleimide and TCEP into the Pneumococcal capsular polysaccharide Pn6b following strategies employed toward the production of conjugate vaccines.
Subject(s)
Phosphines/chemistry , Proteins/chemistry , Alkylating Agents/chemistry , Disulfides/chemistry , Magnetic Resonance Spectroscopy , Maleimides/chemistry , Polysaccharides/chemistry , Solubility , Sulfhydryl Reagents/chemistry , Sulfones/chemistry , WaterABSTRACT
Microscopic plastic debris (microplastics, <5 mm in diameter) is ubiquitous in the marine environment. Previous work has shown that microplastics may be ingested and inhaled by the shore crab Carcinus maenas, although the biological consequences are unknown. Here, we show that acute aqueous exposure to polystyrene microspheres (8 µm) with different surface coatings had significant but transient effects on branchial function. Microspheres inhaled into the gill chamber had a small but significant dose-dependent effect on oxygen consumption after 1 h of exposure, returning to normal levels after 16 h. Ion exchange was also affected, with a small but significant decrease in hemolymph sodium ions and an increase in calcium ions after 24 h post-exposure. To further asses the effects on osmoregulation, we challenged crabs with reduced salinity after microplastic exposure. Neither microspheres nor natural sediments altered the crab's response to osmotic stress regardless of plastic concentration added. Carboxylated (COOH) and aminated (NH2) polystyrene microspheres were distributed differently across the gill surface, although neither had a significant adverse impact on gill function. These results illustrate the extent of the physiological effects of microplastics compared to the physiological resilience of shore crabs in maintaining osmoregulatory and respiratory function after acute exposure to both anthropogenic plastics and natural particles.
Subject(s)
Brachyura/drug effects , Gills/drug effects , Animals , Hemolymph , Plastics/pharmacology , SalinityABSTRACT
In the UK, the Norway lobster (Nephrops norvegicus) supports its most important shellfish fishery. Nephrops are sold either whole, or as "tails-only" for the scampi trade. In the "tailing" process, the "head" (cephalothorax) is discarded as waste. A smaller crustacean species, the Antarctic krill Euphasia superba, represents an economically valuable industry, as its extractable oil is sold as a human dietary supplement. The aim of this study was to determine the amount and composition of the oil contained in discarded Nephrops heads and to compare its composition to the oil extracted from krill. Differences due to Geographical variation and seasonal patterns in the amount and composition of lipid were also noted. Results indicated that Nephrops head waste samples collected from more southern locations in Scotland (Clyde Sea area) contained higher levels of oil when compared to samples collected from northern locations in Iceland. Moreover, seasonal differences within the Clyde Sea area in Scotland were also observed, with oil extracted from Nephrops head waste peaking at around 11.5% during the summer months when larger and more mature females were caught by trawl. At this time of the year, the valuable fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) accounted for around 23% of the total fatty acid content in oil extracted from Nephrops head waste. A seasonal effect on EPA content was found, with higher levels obtained in the summer, while no trend was found in DHA percentages. Finally, oil from Nephrops head waste contained a higher proportion of EPA and DHA than krill oil but these fatty acids were more abundantly linked to the neutral lipids rather to than polar lipids. The characterization of lipid that could be extracted from Nephrops head waste should be seen as a first step for the commercial use of a valuable resource currently wasted. This approach is extremely relevant given the current limited supply of EPA and DHA and changes in the Common Fisheries Policy.
Subject(s)
Euphausiacea/chemistry , Lipids/chemistry , Nephropidae/chemistry , Oils/chemistry , Animals , Antarctic Regions , Dietary Supplements , Docosahexaenoic Acids/chemistry , Eicosapentaenoic Acid/chemistry , Fatty Acids/chemistry , Female , Fish Oils/chemistry , Male , Norway , Scotland , ShellfishABSTRACT
Microscopic plastic fragments (<5 mm) are a worldwide conservation issue, polluting both coastal and marine environments. Fibers are the most prominent plastic type reported in the guts of marine organisms, but their effects once ingested are unknown. This study investigated the fate of polypropylene rope microfibers (1-5 mm in length) ingested by the crab Carcinus maenas and the consequences for the crab's energy budget. In chronic 4 week feeding studies, crabs that ingested food containing microfibers (0.3-1.0% plastic by weight) showed reduced food consumption (from 0.33 to 0.03 g d(-1)) and a significant reduction in energy available for growth (scope for growth) from 0.59 to -0.31 kJ crab d(-1) in crabs fed with 1% plastic. The polypropylene microfibers were physically altered by their passage through the foregut and were excreted with a smaller overall size and length and amalgamated into distinctive balls. These results support of the emerging paradigm that a key biological impact of microplastic ingestion is a reduction in energy budgets for the affected marine biota. We also provide novel evidence of the biotransformations that can affect the plastics themselves following ingestion and excretion.
Subject(s)
Brachyura/drug effects , Brachyura/physiology , Ecotoxicology/methods , Energy Metabolism/drug effects , Plastics/analysis , Water Pollutants, Chemical/analysis , Animals , Aquatic Organisms , Brachyura/growth & development , Eating , Polypropylenes/administration & dosage , Polypropylenes/analysis , Toxicity Tests, Chronic , Water Pollutants, Chemical/administration & dosageABSTRACT
Microplastics, plastics particles <5 mm in length, are a widespread pollutant of the marine environment. Oral ingestion of microplastics has been reported for a wide range of marine biota, but uptake into the body by other routes has received less attention. Here, we test the hypothesis that the shore crab (Carcinus maenas) can take up microplastics through inspiration across the gills as well as ingestion of pre-exposed food (common mussel Mytilus edulis). We used fluorescently labeled polystyrene microspheres (8-10 µm) to show that ingested microspheres were retained within the body tissues of the crabs for up to 14 days following ingestion and up to 21 days following inspiration across the gill, with uptake significantly higher into the posterior versus anterior gills. Multiphoton imaging suggested that most microspheres were retained in the foregut after dietary exposure due to adherence to the hairlike setae and were found on the external surface of gills following aqueous exposure. Results were used to construct a simple conceptual model of particle flow for the gills and the gut. These results identify ventilation as a route of uptake of microplastics into a common marine nonfilter feeding species.
Subject(s)
Brachyura/metabolism , Mytilus edulis/metabolism , Plastics/pharmacokinetics , Water Pollutants, Chemical/pharmacokinetics , Animals , Brachyura/chemistry , Feeding Behavior , Food Chain , Gills/metabolism , Microscopy, Fluorescence , Microspheres , Models, Biological , Mytilus edulis/chemistry , Plastics/chemistry , Plastics/toxicity , Polystyrenes/chemistry , Polystyrenes/pharmacokinetics , Polystyrenes/toxicity , Spectrum Analysis, Raman , Tissue Distribution , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/toxicityABSTRACT
Glomus tumors are rare mesenchymal neoplasms of the subcutaneous tissue, most frequently found in the distal extremities. They are typically benign, but malignant glomus tumors have been described in the literature. Here we present a patient found to have a unilateral renal mass with pathology displaying a primary renal glomus tumor with malignant features. Review of the literature reveals only three cases of malignant glomus tumors and five glomus tumors with malignant potential. As such, previous initial presentations, current criteria for glomus tumor malignancy, and previous treatment outcomes of these cases were reviewed.
ABSTRACT
Monoclonal antibodies (mAbs) have revolutionised the biopharmaceutical market. Being proteinaceous, mAbs are prone to chemical and physical instabilities. Various approaches were attempted to stabilise proteins against degradation factors. Ionic liquids (ILs) and deep eutectic solvents (DESs) have been established as green solvents for ever-increasing pharmaceutical and biopharmaceutical applications. Hence, amino acid (AA)-based ILs, were used for the first time, for mAb stabilisation. Choline (Ch)-based DESs were also utilised for comparison purposes. The prepared ILs and DESs were utilised to stabilise Atezolizumab (Amab, anti-PDL-1 mAb). The formulations of Amab in ILs and DESs were incubated at room temperature, 45 or 55 °C. Following this, the structural stability of Amab was appraised. Interestingly, Ch-Valine retained favourable structural stability of Amab with minimal detected aggregation or degradation as confirmed by UV-visible spectroscopy and protein Mass Spectroscopy. The measured hydrodynamic diameter of Amab in Ch-Valine ranged from 10.40 to 11.65 nm. More interestingly, the anticancer activity of Amab was evaluated, and Ch-Valine was found to be optimum in retaining the activity of Amab when compared to other formulations, including the control Amab sample. Collectively, this study has spotlighted the advantages of adopting the Ch-AA ILs for the structural and functional stabilising of mAbs.
Subject(s)
Amino Acids , Antibodies, Monoclonal, Humanized , Antineoplastic Agents , Ionic Liquids , Ionic Liquids/chemistry , Antibodies, Monoclonal, Humanized/chemistry , Antibodies, Monoclonal, Humanized/pharmacology , Humans , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Amino Acids/chemistry , Colloids/chemistry , Drug Stability , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/pharmacology , Protein Stability , Temperature , Cell Line, Tumor , Solvents/chemistryABSTRACT
Two series of peptidomimetics were designed, prepared and evaluated for their anti-HCV activity. One series possesses a C-terminal carboxylate functionality. In the other series, the electrophilic vinyl sulfonate moiety was introduced as a novel class of HCV NS3/4A protease inhibitors. In vitro based studies were then performed to evaluate the efficacies of the inhibitors using Human hepatoma cells, with the vinyl sulfonate ester (10) in particular, found to have highly potent anti-HCV activity with an EC(50) = 0.296 µM. Finally, molecular modeling studies were performed through docking of the synthesized compounds in the HCV NS3/4A protease active site to assess their binding modes with the enzyme and gain further insight into their structure-activity relationships.