Active aerosols.

We report the dynamics and control of the orientational and positional order of ensembles of gold nanorods suspended in air at standard temperature and pressure using externally applied electric fields, demonstrating an active aerosol. Light filter, valve and gradient responses are shown, establishing active aerosols as a unique type of optical element we term component-less optics.

Light tunable plasmonic metasurfaces.

Self-assembled plasmonic metasurfaces are promising optical platforms to achieve accessible flat optics, due to their strong light-matter interaction, nanometer length scale precision, large area, light weight, and high-throughput fabrication. Here, using photothermal continuous wave laser lithography, we show the spectral and spatial tuning of metasurfaces comprised of a monolayer of ligand capped hexagonally packed gold nanospheres. To tune the spectral response of the metasurfaces, we show that by controlling the intensity of a laser focused onto the metasurface that the absorption peak can be reconfigured from the visible to near-infrared wavelength. The irreversible spectral tuning mechanism is attributed to photothermal modification of the surface morphology. Combining self-assembled metasurfaces with laser lithography, we demonstrate an optically thin (λ/42), spectrally selective plasmonic Fresnel zone plate. This work establishes a new pathway for creating flat, large area, frequency selective optical elements using self-assembled plasmonic metasurfaces and laser lithography.

Iron Bioavailability from Ferric Pyrophosphate in Extruded Rice Cofortified with Zinc Sulfate Is Greater than When Cofortified with Zinc Oxide in a Human Stable Isotope Study.

Background: Extruded rice grains are often cofortified with iron and zinc. However, it is uncertain if the addition of zinc to iron-fortified rice affects iron absorption and whether this is zinc-compound specific.Objective: We investigated whether zinc, added as zinc oxide (ZnO) or zinc sulfate (ZnSO4), affects human iron absorption from extruded rice fortified with ferric pyrophosphate (FePP).Methods: In 19 iron-depleted Swiss women (plasma ferritin ≤16.5 µ/L) aged between 20 and 39 y with a normal body mass index (in kg/m2; 18.7-24.8), we compared iron absorption from 4 meals containing fortified extruded rice with 4 mg Fe and 3 mg Zn. Three of the meals contained extruded rice labeled with FePP (57FePP): 1) 1 meal without added zinc (57FePP-Zn), 2) 1 cofortified with ZnO (57FePP+ZnO), and 3) 1 cofortified with ZnSO4 (57FePP+ZnSO4). The fourth meal contained extruded rice without iron or zinc, extrinsically labeled with ferrous sulfate (58FeSO4) added as a solution after cooking. All 4 meals contained citric acid. Iron bioavailability was measured by isotopic iron ratios in red blood cells. We also measured relative in vitro iron solubility from 57FePP-Zn, 57FePP+ZnO, and 57FePP+ZnSO4 expressed as a fraction of FeSO4 solubility.Results: Geometric mean fractional iron absorption (95% CI) from 57FePP+ZnSO4 was 4.5% (3.4%, 5.8%) and differed from 57FePP+ZnO (2.7%; 1.8%, 4.1%) (P < 0.03); both did not differ from 57FePP-Zn: 4.0% (2.8%, 5.6%). Relative iron bioavailabilities compared with 58FeSO4 were 62%, 57%, and 38% from 57FePP+ZnSO4, 57FePP-Zn, and 57FePP+ZnO, respectively. In vitro solubility from 57FePP+ZnSO4 differed from that of 57FePP-Zn (14.3%; P < 0.02) but not from that of 57FePP+ZnO (10.2% compared with 13.1%; P = 0.08).Conclusions: In iron-depleted women, iron absorption from FePP-fortified extruded rice cofortified with ZnSO4 was 1.6-fold (95% CI: 1.4-, 1.9-fold) that of rice cofortified with ZnO. These findings suggest that ZnSO4 may be the preferable zinc cofortificant for optimal iron bioavailability of iron-fortified extruded rice. This trial was registered at clinicaltrials.gov as NCT02255942.

Rheumatoid meningitis.

Rheumatoid meningitis is a rare, potentially treatable condition that can mimic a wide range of neurological conditions, including vascular syndromes and encephalopathies. Despite a concurrent history of rheumatoid arthritis, patients often have no active synovitis. Here we describe a patient with rheumatoid meningitis who presented to a hyperacute stroke unit with dysarthria on waking and transient facial droop.

Imaging nano-objects by linear and nonlinear optical absorption microscopies.

Absorption based microscopy measurements are emerging as important tools for studying nanomaterials. This review discusses the three most common techniques for performing these experiments: transient absorption microscopy, photothermal heterodyne imaging, and spatial modulation spectroscopy. The focus is on the application of these techniques to imaging and detection, using examples taken from the authors' laboratory. The advantages and disadvantages of the three methods are discussed, with an emphasis on the unique information that can be obtained from these experiments, in comparison to conventional emission or scattering based microscopy experiments.

Myopericytoma of the posterior cranial fossa.

Myopericytoma is a soft tissue tumour believed to be derived from perivascular myoid cells. They are typically found in subcutaneous tissues in the extremities. Intracranial myopericytomas are exceptionally rare. Here we report a man with an asymptomatic posterior fossa myopericytoma with evidence of dural infiltration.

The relative bioavailability of the calcium salt of ß-hydroxy-ß-methylbutyrate is greater than that of the free fatty acid form in rats.

BACKGROUND: ß-Hydroxy-ß-methylbutyrate (HMB) supplementation has been demonstrated to enhance muscle protein synthesis and attenuate loss of muscle mass by multiple pathways. The beneficial effects of HMB have been studied by using either the calcium salt, monohydrate, of HMB (CaHMB) or the free acid form (FAHMB). OBJECTIVE: The present study was designed to compare the pharmacokinetics and relative bioavailability of the 2 forms of HMB administered as a liquid suspension in male Sprague-Dawley rats. METHODS: CaHMB at 30, 100, and 300 mg/kg and equivalent doses of FAHMB at 24.2, 80.8, and 242 mg/kg were administered orally as a liquid suspension to male Sprague-Dawley rats. A single i.v. dose of 5 mg/kg CaHMB, corresponding to an equivalent dose of 4.04 mg/kg FAHMB, was also administered. Plasma concentrations of HMB were analyzed by liquid chromatography tandem mass spectrometry, and pharmacokinetic variables and relative bioavailability of the 2 forms of HMB were determined. RESULTS: After oral administration, the area under the plasma concentration time curve (AUC) from time 0 to time t (0-t) and from time 0 to infinity (0-∞) and the maximum (peak) plasma concentration (Cmax) for CaHMB were significantly greater than for FAHMB, whereas the time to reach Cmax did not differ from that of FAHMB. The relative bioavailability of CaHMB was 49%, 54%, and 27% greater than that of FAHMB for the 3 respective oral doses tested. After i.v. administration, the AUCs 0-t and 0-∞ of the calcium salt were significantly greater than those of FAHMB. The relative bioavailability of CaHMB was 80% greater than that of FAHMB. The higher relative bioavailability of CaHMB may be attributable to its low systemic clearance compared with FAHMB. CONCLUSIONS: This study demonstrates the enhanced relative bioavailability of CaHMB compared with FAHMB. Further studies are warranted to understand the physiologic mechanisms contributing to the differences in systemic clearance.

Upbeat nystagmus in anti-Ma2 encephalitis.

Anti-Ma2 encephalitis is a paraneoplastic disorder characterised by brainstem and/or limbic involvement. Eye movement abnormalities can occur in this condition, often with confusion or somnolence. We describe a patient with progressive oscillopsia (with upbeat nystagmus) and unsteadiness, followed by acute pancreatitis. She did not respond to immunomodulatory treatment and subsequently died of complications related to pancreatitis and sepsis. There was no tumour identified at autopsy, but the anti-Ma2 antibodies in her serum and the discovery of a brainstem-predominant inflammatory infiltrate at autopsy strongly suggest a paraneoplastic disorder. Our case illustrates that upbeat nystagmus can be a predominant feature in anti-Ma2 encephalitis; clinicians should consider testing for anti-Ma2 antibodies in patients with upbeat nystagmus of unknown cause.

Interhemispheric temporal lobe connectivity predicts language impairment in adolescents born preterm.

Although language difficulties are common in children born prematurely, robust neuroanatomical correlates of these impairments remain to be established. This study investigated whether the greater prevalence of language problems in preterm (versus term-born) children might reflect injury to major intra- or interhemispheric white matter pathways connecting frontal and temporal language regions. To investigate this, we performed a comprehensive assessment of language and academic abilities in a group of adolescents born prematurely, some of whom had evidence of brain injury at birth (n = 50, mean age: 16 years, mean gestational age: 27 weeks) and compared them to a term-born control group (n = 30). Detailed structural magnetic resonance imaging and diffusion-tractography analyses of intrahemispheric and interhemispheric white matter bundles were performed. Analysis of intrahemispheric pathways included the arcuate fasciculus (dorsal language pathway) and uncinate fasciculus/extreme capsule (ventral language pathway). Analysis of interhemispheric pathways (in particular, connections between the temporal lobes) included the two major commissural bundles: the corpus callosum and anterior commissure. We found language impairment in 38% of adolescents born preterm. Language impairment was not related to abnormalities of the arcuate fasciculus (or its subsegments), but was associated with bilateral volume reductions in the ventral language pathway. However, the most significant volume reduction was detected in the posterior corpus callosum (splenium), which contains interhemispheric connections between the occipital, parietal and temporal lobes. Diffusion tractography showed that of the three groups of interhemispheric fibres within the splenium, only those connecting the temporal lobes were reduced. Crucially, we found that language impairment was only detectable if the anterior commissure (a second temporal lobe commissural pathway) was also small. Regression analyses showed that a combination of anatomical measures of temporal interhemispheric connectivity (through the splenium of the corpus callosum and anterior commissure) explained 57% of the variance in language abilities. This supports recent theories emphasizing the importance of interhemispheric connections for language, particularly in the developing brain.

Detection of single gold nanoparticles using spatial modulation spectroscopy implemented with a galvo-scanning mirror system.

The optical extinction of single nanoparticles can be sensitively detected by spatial modulation spectroscopy (SMS), where the particle is moved in and out of a tightly focused laser beam with a piezo-device. Here we show that high sensitivity can be obtained by modulating the beam with a galvo-mirror system, rather than by moving the sample. This work demonstrates an inexpensive method for making a SMS microscope, and shows how an existing laser scanning microscope can be adapted for SMS measurements. The galvo-mirror technique also allows SMS measurements to be performed in a liquid, which is difficult to do with piezo-modulation.

Rogue ocean waves and the St. Petersburg paradox.

Powerful rogue ocean waves have been objects of fascination for centuries. Elusive and awe-inspiring, with the potential to inflict catastrophic damage, rogue waves remain unpredictable and imperfectly understood. To gain further insight into their behavior, we analyzed 3 441 188 683 ocean surface waves to determine the statistical height distribution of the largest waves. We found that the distribution of rare events which resolves the St. Petersburg paradox also describes the relative height distribution of the largest waves. This result is expected to contribute to the modeling of ocean surface dynamics and improve the accuracy of marine weather forecasts.

Development and assessment of an x-ray tube-based multi-beam x-ray scatter projection imaging system.

Coherent scatter x-ray imaging systems are sensitive to material structure and chemical composition, and generate soft-material images with contrast superior to conventional transmission x-ray imaging. For practicality in medical or security applications, the image data acquisition time should be <10 min. Our approach is a multi-beam projection imaging design. Previously, as a development stage, we implemented a synchrotron-based system with five coplanar pencil beams and continuous motion of the object. In the work reported here, we developed a more practical coherent scatter projection imaging system using a conventional x-ray tube source. The object is irradiated by an array of up to three rows by five columns of pencil beams, and motorized stages translate the object through the beams for step-and-shoot acquisition. For the same tube loading, broad spectrum beams, such as 110 kVp filtered with 2.25 mm Al, were found to provide a higher signal-difference-to-noise ratio between soft materials in scatter images than lower kVp, more heavily filtered beams that have a narrower, lower intensity spectrum. The shortest acquisition time for a 6.0 × 10.0 cm2 object with 6000 pixels was 8.8 min. The width of a sharp edge in the scatter image was consistent with the pencil beam diameter. Contrast-detail performance was similar to our synchrotron-based system. In this first x-ray tube-based system, for simplicity, the transmitted x rays are measured through attenuators using the same flat-panel detector that measures scattered x rays. As a result, the primary image quality was reduced.

Substantial Depletion of Vicine, Levodopa, and Tyramine in a Fava Bean Protein-Based Nutritional Product.

A commercial fava bean protein isolate and a liquid nutritional product formulated with it were tested by validated HPLC methods for the favism-associated pyrimidine glycoside vicine, the dopamine precursor levodopa, and the biogenic amine tyramine. The vicine, levodopa, and tyramine concentrations in the protein isolate-306, 13.3, and <0.5 mg/kg, respectively-when expressed on a protein basis-34, 1.5, and <0.06 mg/100 g protein, respectively-were at least 96% lower than the vicine, levodopa, and tyramine (protein-based) concentrations reported for fava beans (≥900, ~200, and ~4 mg/100 g protein, respectively). This was also true for the vicine (13 mg/kg or 22 mg/100 g protein), levodopa (≤0.17 mg/kg or ≤0.3 mg/100 g protein), and tyramine (0.08 mg/kg or 0.14 mg/100 g protein) concentrations in the nutritional product. On the basis of these data, one serving (11 fl. oz.) of the nutritional product would deliver approximately 5 mg of vicine, <1 mg of levodopa, and <0.1 mg of tyramine.

Cocoa Flavanols Improve Vascular Responses to Acute Mental Stress in Young Healthy Adults.

Mental stress has been shown to induce cardiovascular events, likely due to its negative impact on vascular function. Flavanols, plant-derived polyphenolic compounds, improve endothelial function and blood pressure (BP) in humans, however their effects during stress are not known. This study examined the effects of acute intake of cocoa flavanols on stress-induced changes on vascular function. In a randomised, controlled, double-blind, cross-over intervention study, 30 healthy men ingested a cocoa flavanol beverage (high-flavanol: 150 mg vs. low-flavanol < 4 mg (-)-epicatechin) 1.5 h before an 8-min mental stress task). Forearm blood flow (FBF), BP, and cardiovascular activity were assessed pre- and post-intervention, both at rest and during stress. Endothelial function (brachial flow-mediated dilatation, FMD) and brachial BP were measured before the intervention and 30 and 90 min post-stress. FMD was impaired 30 min post-stress, yet high-flavanol cocoa attenuated this decline and remained significantly higher compared to low-flavanol cocoa at 90 min post-stress. High-flavanol cocoa increased FBF at rest and during stress. Stress-induced cardiovascular and BP responses were similar in both conditions. Flavanols are effective at counteracting mental stress-induced endothelial dysfunction and improving peripheral blood flow during stress. These findings suggest the use of flavanol-rich dietary strategies to protect vascular health during stress.

Dietary flavanols improve cerebral cortical oxygenation and cognition in healthy adults.

Cocoa flavanols protect humans against vascular disease, as evidenced by improvements in peripheral endothelial function, likely through nitric oxide signalling. Emerging evidence also suggests that flavanol-rich diets protect against cognitive aging, but mechanisms remain elusive. In a randomized double-blind within-subject acute study in healthy young adults, we link these two lines of research by showing, for the first time, that flavanol intake leads to faster and greater brain oxygenation responses to hypercapnia, as well as higher performance only when cognitive demand is high. Individual difference analyses further show that participants who benefit from flavanols intake during hypercapnia are also those who do so in the cognitive challenge. These data support the hypothesis that similar vascular mechanisms underlie both the peripheral and cerebral effects of flavanols. They further show the importance of studies combining physiological and graded cognitive challenges in young adults to investigate the actions of dietary flavanols on brain function.

DNA methylation-based profiling for paediatric CNS tumour diagnosis and treatment: a population-based study.

BACKGROUND: Marked variation exists in the use of genomic data in tumour diagnosis, and optimal integration with conventional diagnostic technology remains uncertain despite several studies reporting improved diagnostic accuracy, selection for targeted treatments, and stratification for trials. Our aim was to assess the added value of molecular profiling in routine clinical practice and the impact on conventional and experimental treatments. METHODS: This population-based study assessed the diagnostic and clinical use of DNA methylation-based profiling in childhood CNS tumours using two large national cohorts in the UK. In the diagnostic cohort-which included routinely diagnosed CNS tumours between Sept 1, 2016, and Sept 1, 2018-we assessed how the methylation profile altered or refined diagnosis in routine clinical practice and estimated how this would affect standard patient management. For the archival cohort of diagnostically difficult cases, we established how many cases could be solved using modern standard pathology, how many could only be solved using the methylation profile, and how many remained unsolvable. FINDINGS: Of 484 patients younger than 20 years with CNS tumours, 306 had DNA methylation arrays requested by the neuropathologist and were included in the diagnostic cohort. Molecular profiling added a unique contribution to clinical diagnosis in 107 (35%; 95% CI 30-40) of 306 cases in routine diagnostic practice-providing additional molecular subtyping data in 99 cases, amended the final diagnosis in five cases, and making potentially significant predictions in three cases. We estimated that it could change conventional management in 11 (4%; 95% CI 2-6) of 306 patients. Among 195 historically difficult-to-diagnose tumours in the archival cohort, 99 (51%) could be diagnosed using standard methods, with the addition of methylation profiling solving a further 34 (17%) cases. The remaining 62 (32%) cases were unresolved despite specialist pathology and methylation profiling. INTERPRETATION: Together, these data provide estimates of the impact that could be expected from routine implementation of genomic profiling into clinical practice, and indicate limitations where additional techniques will be required. We conclude that DNA methylation arrays are a useful diagnostic adjunct for childhood CNS tumours. FUNDING: The Brain Tumour Charity, Children with Cancer UK, Great Ormond Street Hospital Children's Charity, Olivia Hodson Cancer Fund, Cancer Research UK, and the National Institute of Health Research.

Carbonyl-chlorido(1-methyl-sulfanylpenta-1,3-dien-1-yl-5-yl-idene)bis-(triphenyl-phosphane)osmium(II).

The crystal structure of the title compound, [Os(C(6)H(7)S)Cl(C(18)H(15)P)(2)(CO)], confirms the formulation as an osmabenzene. There is a slightly distorted octa-hedral coordination environment at the Os(II) ion, with the triphenyl-phosphane ligands mutually trans and the chloride cis to the carbon bearing the -SMe substituent. Within the metallacyclic ring, the C-C distances are appropriate for aromatic bonds and the two Os-C distances are shorter than typical Os-C single bonds. The maximum deviation from the least-squares plane through the osmabenzene ring occurs for the carbon bearing the SMe substituent [0.1037 (18) Å].

Development and assessment of a multi-beam continuous-phantom-motion x-ray scatter projection imaging system.

X-ray image formation using scattered radiation can yield a superior contrast-to-noise ratio compared to conventional transmission x-ray imaging. A barrier to practical implementation of scatter imaging systems has been slow image acquisition. We have developed a projection imaging system which uses five monoenergetic pencil beams in combination with continuous phantom motion to achieve acquisition times that are practical for medical and security applications. The system was configured at the Canadian Light Source synchrotron and consists of a primary collimator, motorized stages for phantom translation, a flat-panel x-ray detector for measuring scattered x rays, and photodiodes for simultaneously measuring transmitted x rays. Image generation requires several corrections to raw data artifacts arising from the nature of the detector, x-ray source, and acquisition procedure. We developed a novel correction for pixel location inaccuracy arising from continuous phantom motion. A five-beam system had nearly five times faster acquisition than a single-beam system. Continuous motion acquisition was approximately 30 times faster than step-and-shoot acquisition. The total acquisition time for a 9 cm × 5 cm phantom with 8425 pixels was just over 2 min. Image quality was also assessed, in part to determine its relation to acquisition speed. The width of sharp material boundaries was found to be at a minimum equal to the pencil beam width (1.75 mm) and to have an additional width equal to the product of the phantom translation speed and the acquisition time per pixel (up to 1.0 mm in our experiments). Contrast-detail performance was independent of acquisition speed, depending only on phantom entrance x-ray fluence. Pixel signal-to-noise ratio measurements indicate that detector readout noise is important for the scatter data, even for phantom air kerma as high as 30 mGy. Images could be improved with a detector having lower readout noise and higher sensitivity. Its spatial resolution could be moderate. We confirmed that for the same range of λ-1 sin(θ/2), where λ is the x-ray wavelength and θ is the scattering angle, scatter images acquired using different beam energies (33-70 keV) had nearly identical contrast.

Polyphenol-Enriched Plum Extract Enhances Myotubule Formation and Anabolism while Attenuating Colon Cancer-induced Cellular Damage in C2C12 Cells.

Preventing muscle wasting in certain chronic diseases including cancer is an ongoing challenge. Studies have shown that polyphenols derived from fruits and vegetables shows promise in reducing muscle loss in cellular and animal models of muscle wasting. We hypothesized that polyphenols derived from plums (Prunus domestica) could have anabolic and anti-catabolic benefits on skeletal muscle. The effects of a polyphenol-enriched plum extract (PE60) were evaluated in vitro on C2C12 and Colon-26 cancer cells. Data were analyzed using a one-way ANOVA and we found that treatment of myocytes with plum extract increased the cell size by ~3-fold (p < 0.05) and stimulated myoblast differentiation by ~2-fold (p < 0.05). Plum extract induced total protein synthesis by ~50% (p < 0.05), reduced serum deprivation-induced total protein degradation by ~30% (p < 0.05), and increased expression of Insulin-Like Growth Factor-1 (IGF-1) by ~2-fold (p < 0.05). Plum extract also reduced tumor necrosis factor α (TNFα)-induced nuclear factor κB (NFκB) activation by 80% (p < 0.05) in A549/NF-κB-luc cells. In addition, plum extract inhibited the growth of Colon-26 cancer cells, and attenuated cytotoxicity in C2C12 myoblasts induced by soluble factors released from Colon-26 cells. In conclusion, our data suggests that plum extract may have pluripotent health benefits on muscle, due to its demonstrated ability to promote myogenesis, stimulate muscle protein synthesis, and inhibit protein degradation. It also appears to protect muscle cell from tumor-induced cytotoxicity.

Analyzing fidelity and reproducibility of DNA templated plasmonic nanostructures.

Synthetic DNA templated nanostructures offer an excellent platform for the precise spatial and orientational positioning of organic and inorganic nanomaterials. Previous reports have shown its applicability in the organization of plasmonic nanoparticles in a number of geometries for the purpose of realizing tunable nanoscale optical devices. However, translation of nanoparticle-DNA constructs to application requires additional efforts to increase scalability, reproducibility, and formation yields. Understanding all these factors is, in turn, predicated on in-depth analysis of each structure and comparing how formation changes with complexity. Towards the latter goal, we assemble seven unique plasmonic nanostructure symmetries of increasing complexity based on assembly of gold nanorods and nanoparticles on two different DNA origami templates, a DNA triangle and rhombus, and characterize them using gel electrophoresis, atomic force- and transmission electron microscopy, as well as optical spectroscopy. In particular, we focus on how much control can be elicited over yield, reproducibility, shape, size, inter-particle angles, gaps, and plasmon shifts as compared to expectations from computer simulations as structural complexity increases. We discuss how these results can contribute to establishing process principles for creating DNA templated plasmonic nanostructures.