1,105 research outputs found
Have changes in computerised tomography guidance positively impacted detection of cervical spine injury in children? A review of the Trauma Audit and Research Network data
Background
Clinically significant damage to the cervical spine in children is uncommon, but missing this can be life-changing for patients. The balance between rarity and severity leads to inconsistent scanning, with both resource and radiation implications. In 2014, the United Kingdom’s National Institute for Health and Care Excellence updated their computerised tomography neck imaging guidance in children. The aim of this study was to assess if the change in guidance had resulted in a change in diagnosis or imaging rates.
Methods
A retrospective review of the national Trauma Audit and Research Network’s data for computerised tomography spine imaging in children in 2012–2013 was compared to the same data sample collected in 2015–2016.
Results
The percentage of children presenting with neck trauma who were imaged reduced from 15.5 to 14.1% with an increase in confirmed cervical spine injury from 1.6 to 2.3% between the two time periods. The specificity of computerised tomography scanning increased from 10 to 16.4%. There was variation in scan rates, with major trauma centres scanning a greater percentage of children of all ages and with all injury scores, than trauma units.
Discussion
This study suggests national guidance can impact clinical care in a relatively short timeframe. Variation in how guidance is applied, with major trauma centres scanning proportionately more children with a lower yield, could be because scanning is more readily available, or because trauma protocols encourage more scans. Twenty per cent of injuries were not found on the initial computerised tomography, in keeping with previously reported data, because the injuries were ligamentous or cord contusion. This suggests a role for early magnetic resonance imaging in children with suspected spinal injury
Pulsed Doppler lidar airborne scanner
This report covers the work accomplished during the reporting period on Pulsed Doppler Lidar Airborne Scanner and describes plans for the next reporting period. The objectives during the current phase of the contract are divided into four phases. Phase 1 includes ground testing of the system and analysis of data from the 1981 Severe Storms Test Flights. Phase 2 consists of preflight preparation and planning for the 1983 flight series. The flight test itself will be performed during Phase 3, and Phase 4 consists of post-flight analysis and operation of the system after that flight test. The range profile from five samples taken during Flight 10, around 1700 Z is given. The lowest curve is taken from data collected upwind of Mt. Shasta at about 10,000 feet of altitude, in a clear atmosphere, where no signals were observed. It thus is a good representation of the noise level as a function of range. The next curve was taken downwind of the mountain, and shows evidence of atmospheric returns. There is some question as to whether the data are valid at all ranges, or some ranges are contaminated by the others
Effects of Acute and Sustained Pain Manipulations on Performance in a Visual‐Signal Detection Task of Attention in Rats
Preclinical ResearchPatients with pain often display cognitive impairment including deficits in attention. The visual‐signal detection task (VSDT) is a behavioral procedure for assessment of attention in rodents. Male Sprague Dawley rats were trained in a VSDT and tested with three different noxious stimuli: (i) intraperitoneal injection of lactic acid; (ii) intraplantar injection of formalin; and (iii) intraplantar injection of complete Freund's adjuvant (CFA). The muscarinic acetylcholine receptor antagonist, scopolamine was also tested as a positive control. Scopolamine (0.01–1.0 mg/kg) dose dependently reduced accuracy and increased response latencies during completed trials with higher scopolamine doses increasing omissions. Lactic acid (0.56–5.6% ip) also increased response latencies and omissions, although it failed to alter measures of response accuracy. Formalin produced a transient decrease in accuracy while also increasing both response latency and omissions. CFA failed to alter VSDT performance. Although VSDT effects were transient for formalin and absent for CFA, both treatments produced mechanical allodynia and paw edema for up to 7 days. These results support the potential for noxious stimuli to produce a pain‐related disruption of attention in rats. However, relatively strong noxious stimulation appears necessary to disrupt performance in this version of the VSDT. Drug Dev Res 76 : 194–203, 2015. © 2015 Wiley Periodicals, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111955/1/ddr21255.pd
Interaction between Mu and Delta Opioid Receptor Agonists in an Assay of Capsaicin-Induced Thermal Allodynia in Rhesus Monkeys
Delta opioid agonists enhance antinociceptive effects of mu-opioid agonists in many preclinical assays of acute nociception, but delta/mu interactions in preclinical models of inflammation-associated pain have not been examined. This study examined interactions between the delta agonist SNC80 [(+)-4-[(αR)-α-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide] and the mu agonist analgesics methadone, morphine, and nalbuphine in an assay of capsaicin-induced thermal allodynia in rhesus monkeys. Thermal allodynia was produced by topical application of capsaicin to the tail. Antiallodynic effects of methadone, morphine, and nalbuphine were evaluated alone or in combination with fixed proportions of SNC80 identical to proportions previously shown to enhance acute thermal antinociceptive effects of these mu agonists in rhesus monkeys (0.9 : 1 SNC80/methadone; 0.29 : 1 SNC80/morphine; 3.6 : 1 SNC80/nalbuphine). Methadone, morphine, and nalbuphine each produced dose-dependent antiallodynia. SNC80 produced partial antiallodynia up to the highest dose tested (5.6 mg/kg). SNC80 produced a modest, enantioselective, and naltrindole-reversible enhancement of methadone-induced antiallodynia. However, SNC80 did not enhance morphine antiallodynia and only weakly enhanced nalbuphine antiallodynia. Overall, SNC80 produced modest or no enhancement of the antiallodynic effects of the three mu agonists evaluated. These results suggest that delta agonist-induced enhancement of mu agonist antiallodynia may be weaker and less reliable than previously demonstrated enhancement of mu agonist acute thermal nociception
A new narrow-beam, multi-frequency, scanning radiometer and its application to in-flight icing detection
AbstractA one degree beamwidth, multi-frequency (20 to 30 and 89GHz), dual-polarization radiometer with full azimuth and elevation scanning capabilities was built with the purpose of improving the detection of in-flight icing hazards to aircraft in the near airport environment. This goal was achieved by collocating the radiometer with Colorado State University's CHILL polarized Doppler radar and leveraging the similar beamwidth and volume scan regiments of the two instruments. The collocated instruments allowed for the liquid water path and water vapor measurements derived from the radiometer to be merged with the radar moment fields to determine microphysical and water phase characteristics aloft. The radiometer was field tested at Colorado State University's CHILL radar site near Greeley, Colorado during the summer of 2009. Instrument design, calibration, and initial field testing results are discussed in this paper
The Twinning Problem
In the field of crystallography, some crystals are not made of a single component but are instead twinned.In these cases, the observed intensities at some points in the lattice will be far larger than predictions. If we find the rotation associated to the twinned component, we can model this twin and improve our agreement with observations. In this report, we explore many routes to improve the process of identifying twins: Generation of fake data for better understanding and accurate testing. The representation of a rotation as defined by an axis and angle. The representation of a rotation as a quaternion. Using lattice points which must be equidistant from the origin to create our viable rotations. An algorithm focused on restricted possibilities. An exploration of 2D lattices for which twinning is mathematically impossible. We find that there is much to be investigated in the field of twinning
Transcranial direct current stimulation with functional magnetic resonance imaging: a detailed validation and operational guide [version 1; peer review: 1 approved with reservations]
Introduction: Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique used to modulate human brain and behavioural function in both research and clinical interventions. The combination of functional magnetic resonance imaging (fMRI) with tDCS enables researchers to directly test causal contributions of stimulated brain regions, answering questions about the physiology and neural mechanisms underlying behaviour. Despite the promise of the technique, advances have been hampered by technical challenges and methodological variability between studies, confounding comparability/replicability. /
Methods: Here tDCS-fMRI at 3T was developed for a series of experiments investigating language recovery after stroke. To validate the method, one healthy volunteer completed an fMRI paradigm with three conditions: (i) No-tDCS, (ii) Sham-tDCS, (iii) 2mA Anodal-tDCS. MR data were analysed in SPM12 with region-of-interest (ROI) analyses of the two electrodes and reference sites. /
Results: Quality assessment indicated no visible signal dropouts or distortions introduced by the tDCS equipment. After modelling scanner drift, motion-related variance, and temporal autocorrelation, we found no field inhomogeneity in functional sensitivity metrics across conditions in grey matter and in the three ROIs. /
Discussion: Key safety factors and risk mitigation strategies that must be taken into consideration when integrating tDCS into an fMRI environment are outlined. To obtain reliable results, we provide practical solutions to technical challenges and complications of the method. It is hoped that sharing these data and SOP will promote methodological replication in future studies, enhancing the quality of tDCS-fMRI application, and improve the reliability of scientific results in this field. /
Conclusions: The method and data provided here provide a technically safe, reliable tDCS-fMRI procedure to obtain high quality MR data. The detailed framework of the Standard Operation Procedure SOP (https://doi.org/10.5281/zenodo.4606564) systematically reports the technical and procedural elements of our tDCS-fMRI approach, which we hope can be adopted and prove useful in future studies
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Sustained pain-related depression of behavior: effects of intraplantar formalin and complete freund’s adjuvant on intracranial self-stimulation (ICSS) and endogenous kappa opioid biomarkers in rats
Background: Intraplantar administration of complete Freund's adjuvant (CFA) and formalin are two noxious stimuli commonly used to produce sustained pain-related behaviors in rodents for research on neurobiology and treatment of pain. One clinically relevant manifestation of pain is depression of behavior and mood. This study compared effects of intraplantar CFA and formalin on depression of positively reinforced operant behavior in an assay of intracranial self-stimulation (ICSS) in rats. Effects of CFA and formalin on other physiological and behavioral measures, and opioid effects on formalin-induced depression of ICSS, were also examined. Results: There were four main findings. First, consistent with previous studies, both CFA and formalin produced similar paw swelling and mechanical hypersensitivity. Second, CFA produced weak and transient depression of ICSS, whereas formalin produced a more robust and sustained depression of ICSS that lasted at least 14 days. Third, formalin-induced depression of ICSS was reversed by morphine doses that did not significantly alter ICSS in saline-treated rats, suggesting that formalin effects on ICSS can be interpreted as an example of pain-related and analgesic-reversible depression of behavior. Finally, formalin-induced depression of ICSS was not associated with changes in central biomarkers for activation of endogenous kappa opioid systems, which have been implicated in depressive-like states in rodents, nor was it blocked by the kappa antagonist norbinaltorphimine. Conclusions: These results suggest differential efficacy of sustained pain stimuli to depress brain reward function in rats as assessed with ICSS. Formalin-induced depression of ICSS does not appear to engage brain kappa opioid systems. Electronic supplementary material The online version of this article (doi:10.1186/1744-8069-10-62) contains supplementary material, which is available to authorized users
Monocyte chemoattractant protein-1 serum levels in ovarian cancer patients
The chemokine monocyte chemoattractant protein (MCP)-1 is an important mediator of monocyte infiltration in various solid tumours of epithelial origin. The aim of the present study was to evaluate the role of MCP-1 in the natural history of ovarian cancer and to determine its value as differentiation marker and prognostic marker regarding disease free and overall survival. This retrospective study comprises 86 patients with ovarian cancer, 48 with primary ovarian cancer and 38 with recurrent ovarian cancer, 67 patients with benign ovarian cysts and 42 healthy women. Median serum levels in patients with primary ovarian cancer, recurrent ovarian cancer, benign ovarian cysts and in healthy women were 535.6 (range 129.6–1200) pg ml–1, 427.3 (range 193.4–1101) pg ml–1, 371.2 (range 222–986.8) pg ml–1 and 318.7 (range 241.3–681.4) pg ml–1 respectively (Mann–Whitney U-test, P < 0.001). Univariate logistic regression models revealed a significant influence of MCP-1 serum levels on the odds of presenting with primary ovarian cancer versus benign cysts and versus healthy women respectively (univariate logistic regression, P < 0.001 and P < 0.001 respectively). In a multivariate logistic regression model considering MCP-1 and CA 125 serum levels simultaneously, both MCP-1 and CA 125 revealed statistical significance on the odds of presenting with primary ovarian cancer versus benign cysts (multivariate logistic regression, P = 0.05 and P < 0.001 respectively). In ovarian cancer patients, MCP-1 serum levels showed a statistically significant correlation with histological grade (Mann–Whitney U-test, P = 0.02) and age at the time of diagnosis (Mann–Whitney U-test, P = 0.03). Elevated MCP-1 serum levels prior to therapy were not associated with disease-free and overall survival (log-rank test, P = 0.2 and P = 0.7 respectively). In summary these data indicate that MCP-1 might play a functional role in the natural history of ovarian cancer and might serve as differentiation marker between benign ovarian cysts and ovarian cancer, providing additional information to the established tumour marker CA 125. © 1999 Cancer Research Campaig
Safety of tattoos in persons undergoing MRI
In 330 persons who had one to seven tattoos, only one mild tattoo-related adverse reaction was detected during magnetic resonance imaging (MRI). These results suggest a low risk among persons with tattoos when MRI is performed under these specific study conditions
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