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Bright Lu2 O3 :Eu Thin-Film Scintillators for High-Resolution Radioluminescence Microscopy. - Advanced healthcare materials
The performance of a new thin-film Lu2 O3 :Eu scintillator for single-cell radionuclide imaging is investigated. Imaging the metabolic properties of heterogeneous cell populations in real time is an important challenge with clinical implications. An innovative technique called radioluminescence microscopy has been developed to quantitatively and sensitively measure radionuclide uptake in single cells. The most important component of this technique is the scintillator, which converts the energy released during radioactive decay into luminescent signals. The sensitivity and spatial resolution of the imaging system depend critically on the characteristics of the scintillator, that is, the material used and its geometrical configuration. Scintillators fabricated using conventional methods are relatively thick and therefore do not provide optimal spatial resolution. A thin-film Lu2 O3 :Eu scintillator is compared to a conventional 500 Î¼m thick CdWO4 scintillator for radioluminescence imaging. Despite its thinness, the unique scintillation properties of the Lu2 O3 :Eu scintillator allow us to capture single-positron decays with fourfold higher sensitivity, which is a significant achievement. The thin-film Lu2 O3 :Eu scintillators also yield radioluminescence images where individual cells appear smaller and better resolved on average than with the CdWO4 scintillators. Coupled with the thin-film scintillator technology, radioluminescence microscopy can yield valuable and clinically relevant data on the metabolism of single cells.Â© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Foot sensation testing in the patient with diabetes: introduction of the quick & easy assessment tool. - Wounds : a compendium of clinical research and practice
Sensory testing of patients with diabetes is an integral part of preventing new and recurrent wounds. The Semmes- Weinstein monofilament (SWM) test is considered the gold standard to screen for loss of protective sensation; however, the authors' experience has shown that it is not only time consuming, but is of negligible value for a patient with a diabetic foot ulcer (DFU).This article discusses the shortfalls with regard to the SWM test and reviews other techniques for sensory evaluation. In addition, the Quick & Easy system is introduced, which combines sensory assessment with guidance for anesthesia requirements during wound debridements or other surgical interventions.A scale ranging from grade 2 (normal sensation) to grade 0 (absent sensation) reflects the patient's responses to wound manipulation, palpation of an underlying deformity, and/or evaluation of the difference between light touch sensation with the patient's hands compared to the feet. For patients with total loss of sensation (grade 0), no anesthesia is needed for surgical procedures. If there is diminished sensation (grade 1), surgical intervention can be performed following administration of either topical or local anesthesia. For patients with normal sensation (grade 2), complete anesthesia of the surgical site will be required. A preliminary observation was conducted on 50 patients with DFUs using the Quick & Easy system. Anesthetic requirements were accurately predicted in all cases without the need to modify the type of anesthesia during the procedure.The Quick & Easy system serves as a simple sensory evaluation for a patient with a DFU and provides valuable anesthesia guidance for wound care procedures.
Inflammatory cytokines and cellular metabolites as synovial fluid biomarkers of posttraumatic ankle arthritis. - Foot & ankle international
There is a paucity of research on posttraumatic ankle arthritis (PTAA). We aimed to identify synovial fluid PTAA biomarkers using cytokine analysis and metabolic profiling.Ankle joint synovial fluid was obtained from 20 patients with PTAA and 20 patients with no ankle pain and no radiographic evidence of ankle arthritis (control group). Synovial fluid samples were analyzed for IFN-Î³, TNF-Î±, MIP-1Î², MCP-1, IL-1Î², IL-1Ra, IL-4, IL-6, IL-8, IL-10, IL-13, and IL-15 using ELISA and for more than 3000 metabolites using liquid and gas chromatography with mass spectroscopy. To compare presence of cytokines and metabolites between groups, t tests were used. Random forest analysis was performed on metabolites to determine whether control and PTAA samples could be differentiated based on metabolic profile.IL-1Ra, IL-6, IL-8, IL-10, IL-15, and MCP-1 were significantly elevated in the PTAA group. In addition, 107 metabolites in the PTAA group were significantly altered, including derangement in amino acid, carbohydrate, lipid, and energy metabolism, extracellular matrix turnover, and collagen degradation. Random forest analysis yielded a predictive accuracy of 90% when using the metabolic profiles to distinguish between control and PTAA samples.This study identified inflammatory cytokines and metabolites present in the synovial fluid of PTAA.Several of these entities have previously been implicated in rheumatoid arthritis and osteoarthritis of the knee, but many could potentially be used as novel biomarkers of PTAA. Most importantly, the findings suggest that metabolites could be used to distinguish synovial fluid from patients with PTAA.Â© The Author(s) 2014.
Acute effects of a loaded warm-up protocol on change of direction speed in professional badminton players. - Journal of applied biomechanics
It has previously been shown that a loaded warm-up may improve power performances. We examined the acute effects of loaded dynamic warm-up on change of direction speed (CODS), which had not been previously investigated. Eight elite badminton players participated in three sessions during which they performed vertical countermovement jump and CODS tests before and after undertaking the dynamic warm-up. The three warm-up conditions involved wearing a weighted vest (a) equivalent to 5% body mass, (b) equivalent to 10% body mass, and (c) a control where a weighted vest was not worn. Vertical jump and CODS performances were then tested at 15 seconds and 2, 4, and 6 minutes post warm-up. Vertical jump and CODS significantly improved following all warm-up conditions (P < .05). Post warm-up vertical jump performance was not different between conditions (P = .430). Post warm-up CODS was significantly faster following the 5% (P = .02) and 10% (P < .001) loaded conditions compared with the control condition. In addition, peak CODS test performances, independent of recovery time, were faster than the control condition following the 10% loaded condition (P = .012). In conclusion, the current study demonstrates that a loaded warm-up augmented CODS, but not vertical jump performance, in elite badminton players.
Tibialis anterior moment arm: effects of measurement errors and assumptions. - Medicine and science in sports and exercise
Accurate estimates of tibialis anterior (TA) muscle force are important in many contexts. Two approaches commonly used to estimate moment arms are the tendon excursion (TE) and geometric (GEO) methods. Previous studies report poor agreement between the two approaches.The purposes of this study were to 1) assess the effect of methodological variations in the two methods of moment arm estimation and 2) determine how these variations affect agreement between the methods.TA moment arms were determined using TE and GEO. Errors associated with tendon stretch/hysteresis, talus rotation relative to the foot, and the location of the line of action were investigated.For TE, large errors in moment arm estimates across the range of motion were found when tendon length changes (P = 0.001) were not corrected for. For GEO, the estimated moment arm was reduced at an ankle angle of -15Â° when discrepancies between talus and foot rotations were accounted for or when an alternative tendon line of action was used either separately (effect size (ES), 0.46 and 0.58, respectively; P > 0.05) or together (ES, 0.89; P > 0.05). TE-derived moment arms were smaller than GEO-derived moment arms (ES, 0.68-4.86, varying by angle) before accounting for sources of error. However, these differences decreased after error correction (ES, 0.09-1.20, P > 0.05). Nonetheless, the shape of the moment arm-joint angle relation was curvilinear for TE but linear for GEO.Of all methodological modifications, accounting for tendon length changes had the largest effect on TA moment arm estimates. We conclude that the TE method is viable to determine TA moment arms as long as changes in tendon length are accounted for.
In situ energy-dispersive X-ray diffraction for the synthesis optimization and scale-up of the porous zirconium terephthalate UiO-66. - Inorganic chemistry
The synthesis optimization and scale-up of the benchmarked microporous zirconium terephthalate UiO-66(Zr) were investigated by evaluating the impact of several parameters (zirconium precursors, acidic conditions, addition of water, and temperature) over the kinetics of crystallization by time-resolved in situ energy-dispersive X-ray diffraction. Both the addition of hydrochloric acid and water were found to speed up the reaction. The use of the less acidic ZrOCl2Â·8H2O as the precursor seemed to be a suitable alternative to ZrCl4Â·xH2O, avoiding possible reproducibility issues as a consequence of the high hygroscopic character of ZrCl4. ZrOCl2Â·8H2O allowed the formation of smaller good quality UiO-66(Zr) submicronic particles, paving the way for their use within the nanotechnology domain, in addition to higher reaction yields, which makes this synthesis route suitable for the preparation of UiO-66(Zr) at a larger scale. In a final step, UiO-66(Zr) was prepared using conventional reflux conditions at the 0.5 kg scale, leading to a rather high space-time yield of 490 kg m(-3) day(-1), while keeping physicochemical properties similar to those obtained from smaller scale solvothermally prepared batches.
High-speed detector for time-resolved diffraction studies. - Journal of physics. Conference series
There are a growing number of high brightness synchrotron sources that require high-frame-rate detectors to provide the time-scales required for performing time-resolved diffraction experiments. We report on the development of a very high frame rate CMOS X-ray detector for time-resolved muscle diffraction and time-resolved solution scattering experiments. The detector is based on a low-afterglow scintillator, provides a megapixel resolution with frame rates of up to 120,000 frames per second, an effective pixel size of 64 Âµm, and can be adapted for various X-ray energies. The paper describes the detector design and initial results of time-resolved diffraction experiments on a synchrotron beamline.
Herpes simplex meningo-encephalitis following cochlear implantation: a case study. - Cochlear implants international
Herpes simplex virus (HSV) is reported to be the most common cause of viral encephalitis. Although extremely rare, reactivation of the virus has been reported following central nervous system surgery. To the best of our knowledge, there is no report in the literature that describes HSV encephalitis following cochlear implantation.We report a case of meningo-encephalitis occurring 17 days after cochlear implantation using an electro-acoustic stimulation device, with oerioperative steroid medication. Intensive anti-viral therapy was given and the patient recovered from the acute illness over 2 weeks. Agitation and anxiety followed the encephalitis and subsequent progress with the cochlear implant was slow. Twelve months after cochlear implantation this patient shows a gradual and steady progress with her hearing rehabilitation.Cochlear implantation surgery was either coincidental or was the trigger factor for reactivation of the HSV. Surgeons must be vigilant to post-surgical meningism symptoms particularly if patients have a history of herpes infections.
Nondestructive method for quantifying thallium dopant concentrations in CsI:Tl crystals. - Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine
We report a quantitative method for using X-ray fluorescence (XRF) to nondestructively measure the true content of Tl dopant in CsI:Tl scintillator crystals. The instrument is the handheld LeadTracerâ„¢, originally developed at RMD Instruments for measuring Pb concentration in electronic components. We describe both the measurement technique and specific findings on how changes in crystal size and growth parameters affect Tl concentration. This method is also applicable to numerous other activator ions important to scintillators, such as Ce(3+) and Eu(2+).Â© 2013 Elsevier Ltd. All rights reserved.
A rare example of a porous Ca-MOF for the controlled release of biologically active NO. - Chemical communications (Cambridge, England)
A 1D-microporous 3D calcium tetracarboxylate MOF has been solvothermally prepared and its structure solved from single crystal data. It exhibits coordinatively unsaturated Ca(2+) Lewis acid sites able to trap and deliver nitric oxide at a biological level.
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