Σάββατο 26 Μαΐου 2018
Diagnostic performance of magnifying endoscopy with narrow-band imaging in differentiating neoplastic colorectal polyps from non-neoplastic colorectal polyps: a meta-analysis
Abstract
Colorectal polyps are commonly seen in colonoscopy and the management of neoplastic polyps and non-neoplastic polyps are different. It is necessary to distinguish neoplastic polyps from non-neoplastic polyps in real-time. Therefore, we conducted a meta-analysis to assess the diagnostic accuracy of magnifying endoscopy with narrow-band imaging (ME-NBI) in diagnosing neoplastic colorectal polyps from non-neoplastic colorectal polyps. PubMed and EMBASE were searched for trials that used magnifying endoscopy with ME-NBI for diagnosing neoplastic colorectal polyps. Sixteen articles and 20 fourfold tables were obtained. Sensitivity (Sen), specificity (Spe), positive likelihood ratios (+ LRs), negative likelihood ratios (− LRs) and diagnostic odds ratios (DORs) were calculated. A summary receiver-operating characteristic (SROC) curve was constructed, and the area under the ROC curve (AUC) was calculated. We performed subgroup analyses based on polyp size and assessment criteria: (1) According to data extracted from 20 fourfold tables, the pooled Sen and Spe of ME-NBI for diagnosing neoplastic colorectal polyps < 10 mm were 0.94 (95% CI 0.92–0.95) and 0.76 (95% CI 0.72–0.80),respectively. The pooled Sen and Spe of ME-NBI for diagnosing all neoplastic polyps were 0.98 (95% CI 0.98–0.99) and 0.88 (95% CI 0.85–0.90), respectively. (2) Data pertaining to the following three assessment methods were analysed from 15 fourfold tables: surface pattern (SP), vessel pattern (VP) and the combination of SP and VP. The AUCs for these assessment criteria were 0.9533, 0.9518 and 0.9954, respectively. Conclusions were made that ME-NBI has high diagnostic accuracy in diagnosing neoplastic colorectal polyps based on the combination of SP with VP and is helpful in making real-time diagnoses.
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A new method for monitoring abnormal muscle response in hemifacial spasm: A prospective study
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): Seunghoon Lee, Sang-Ku Park, Jeong-A Lee, Byung-Euk Joo, Doo-Sik Kong, Dae-Won Seo, Kwan Park
ObjectiveTo examine a new abnormal muscle response (AMR) monitoring method during microvascular decompression (MVD) for hemifacial spasm.Methods486 patients with hemifacial spasm were monitored for an AMR during MVD with a new method involving preoperative mapping and intraoperative centrifugal stimulation of the facial nerve. For the last 62 patients, we performed the AMR monitoring using both, the new and conventional methods simultaneously.ResultsPreoperative facial nerve mapping showed that the maximal AMR was detected most frequently (66.9%) at the "F" location (the direction towards the frontalis muscle). An intraoperative AMR was observed in 86.2% of the patients, which disappeared after MVD in 96.4% of the patients. A comparison of the new and conventional methods respectively showed that AMR disappearance after MVD was observed in 98.2% and 61.8% of the patients, no AMR in 0% and 9.1%, and persistent AMR after MVD in 1.8% and 29.1%.ConclusionsThe new AMR monitoring method demonstrated greater AMR monitoring efficacy and supports the finding that disappearance of an AMR is a good indicator of effective decompression during MVD surgery.SignificancePreoperative mapping and intraoperative centrifugal stimulation of the facial nerve during MVD surgery in HFS patients showed greater efficacy of AMR monitoring.
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Reply to “Syncope is associated with electroencephalography changes” and to “Video-EEG during tilt-table testing is an invaluable aid for understanding syncope”
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): Srikanth Muppidi, Mitchell G. Miglis, Babak Razavi
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Sharply contoured theta waves are the human correlate of ponto-geniculo-occipital waves in the primary visual cortex
Publication date: August 2018
Source:Clinical Neurophysiology, Volume 129, Issue 8
Author(s): Birgit Frauscher, Sweta Joshi, Nicolas von Ellenrieder, Dang Khoa Nguyen, François Dubeau, Jean Gotman
ObjectivePonto-geniculo-occipital (PGO) waves occurring along the visual axis are one of the hallmarks of REM sleep in experimental animals. In humans, direct evidence is scarce. There is no systematic study of PGO waves in the primary visual cortex.MethodsEleven epilepsy patients undergoing combined intracranial EEG/polysomnography had 71 channels recording physiological EEG activity from various cortical areas; seven channels recorded from the primary visual cortex. An equal number of 4-s phasic and tonic REM segments were selected. Patterns consistent with PGO waves were visually analyzed in both states in the primary visual cortex. Spectral analysis compared activity in the primary visual cortex with the remaining cortical areas.ResultsVisual inspection revealed an increase in sharply contoured theta waves (duration: 150–250 ms) in the primary visual cortex during phasic as compared to tonic REM sleep. Spectral analysis confirmed a 32% increase in mean absolute theta power during phasic versus tonic REM sleep (p corrected = 0.014).ConclusionNo classical PGO waves, but sharply contoured theta waves were found in the human primary visual cortex during phasic as opposed to tonic REM sleep.SignificanceThis research suggests that sharply contoured theta waves are the human correlate of PGO waves described in experimental animal models.
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Editorial Board
Source:Clinical Neurophysiology, Volume 129, Issue 7
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Oh surprise! Fast ripples on scalp EEG
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): Jean Gotman
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Syncope is associated with electroencephalography changes
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): Geoffrey L. Heyer
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Tracking the central and peripheral origin of tremor
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): Ming-Kai Pan, Sheng-Han Kuo
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Measuring neuropathy in obese populations: Challenge accepted. Reply to “Diagnostic accuracy of neuropathy tests in obese population remains elusive”
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): Brian C. Callaghan, Eva L. Feldman
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Normal sensory membrane properties in amyotrophic lateral sclerosis
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): Hessel Franssen
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Amyotrophic lateral sclerosis – Time for beta testing?
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): M.R. Baker, T. Dharmadasa, S.R. Jaiser, M.C. Kiernan
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An improved methodology for intraoperative monitoring of the lateral spreading response during surgery for hemifacial spasm
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): Vedran Deletis, Sedat Ulkatan
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Visual and semi-automatic non-invasive detection of interictal fast ripples: A potential biomarker of epilepsy in children with tuberous sclerosis complex
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): Danilo Bernardo, Hiroki Nariai, Shaun A. Hussain, Raman Sankar, Noriko Salamon, Darcy A. Krueger, Mustafa Sahin, Hope Northrup, E. Martina Bebin, Joyce Y. Wu
ObjectivesWe aim to establish that interictal fast ripples (FR; 250–500 Hz) are detectable on scalp EEG, and to investigate their association to epilepsy.MethodsScalp EEG recordings of a subset of children with tuberous sclerosis complex (TSC)-associated epilepsy from two large multicenter observational TSC studies were analyzed and compared to control children without epilepsy or any other brain-based diagnoses. FR were identified both by human visual review and compared with semi-automated review utilizing a deep learning-based FR detector.ResultsSeven out of 7 children with TSC-associated epilepsy had scalp FR compared to 0 out of 4 children in the control group (p = 0.003). The automatic detector has a sensitivity of 98% and false positive rate with average of 11.2 false positives per minute.ConclusionsNon-invasive detection of interictal scalp FR was feasible, by both visual and semi-automatic detection. Interictal scalp FR occurred exclusively in children with TSC-associated epilepsy and were absent in controls without epilepsy. The proposed detector achieves high sensitivity of FR detection; however, expert review of the results to reduce false positives is advised.SignificanceInterictal FR are detectable on scalp EEG and may potentially serve as a biomarker of epilepsy in children with TSC.
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Impaired corticomuscular and interhemispheric cortical beta oscillation coupling in amyotrophic lateral sclerosis
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): Malcolm Proudfoot, Freek van Ede, Andrew Quinn, Giles L. Colclough, Joanne Wuu, Kevin Talbot, Michael Benatar, Mark W. Woolrich, Anna C. Nobre, Martin R. Turner
ObjectivesThe neural activity of the primary motor cortex is variably synchronised with contralateral peripheral electromyographic signals, which is thought to facilitate long-range communication through the motor system. Such corticomuscular coherence (CMC) is typically observed in the beta-band (15–30 Hz) range during steady force production. We aimed to measure pathological alteration to CMC resulting from ALS.MethodsCMC was appraised during a forearm grip task in 17 ALS patients contrasted against age-matched healthy controls. An exploratory comparison with a group of asymptomatic ALS gene carriers and neuropathy disease mimics was also undertaken. Neural signals were acquired by whole-head magnetoencephalography and localised via structural MRI to the motor cortices.ResultsDuring light voluntary muscular contraction, beta-band CMC was significantly reduced in ALS patients compared to healthy controls. Propagation of motoric beta rhythms across the cortical hemispheres was also shown to be impaired in ALS patients. CMC was preserved in the asymptomatic gene carrier and did not distinguish ALS patients from neuropathy mimics.ConclusionFunctional connectivity metrics reveal an ALS-related decrease in both corticomuscular and interhemispheric communication during bilateral grip force production.SignificanceMEG-derived beta oscillation coupling may be a potential biomarker of motor system dysfunction in ALS, against which to measure future therapeutic efficacy.
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Lack of correlation between phonetic magnetic mismatch field and plasma d-serine levels in humans
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): Motomu Suga, Yuki Kawakubo, Yukika Nishimura, Kenji Hashimoto, Masato Yumoto, Kiyoto Kasai
ObjectiveUncovering molecular bases for auditory language processing in the human brain is a fundamental scientific challenge. The power and latency of the magnetic mismatch field (MMF) elicited by phoneme change, which are magnetoencephalographic indices of language function in its early stage of information processing, are theoretically thought to be modulated by N-methyl-d-aspartate-type glutamate receptor (NMDAR) function, but no study has yet assessed this possibility. We have thus sought to demonstrate an association between phonetic MMF power/latency and levels of plasma d-serine, an intrinsic co-agonist of glycine binding sites on NMDAR, in adults.MethodsThe MMF response to phoneme changes was recorded using 204-channel magnetoencephalography in 61 healthy, right-handed, Japanese adults. Plasma levels of d- and l-serine were measured for each participant.ResultsWe did not find a significant correlation between MMF power/latency and plasma serine levels.ConclusionsDespite a sufficient sample size, we failed to find an association between the physiological markers of the early stage of information processing of language in the auditory cortex and biomarkers indexing glutamatergic function.SignificanceOur study did not indicate that a molecular index of glutamatergic function could be a surrogate marker for the early stage of information processing of language in humans.
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Video-EEG during tilt-table testing is an invaluable aid for understanding syncope
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): J. Gert van Dijk, Roland D. Thijs, Martijn R. Tannemaat, David G. Benditt
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Diagnostic accuracy of neuropathy tests in obese population remains elusive
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): Aaron I. Vinik, Marie-Laure Névoret
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The response of the central and peripheral tremor component to octanoic acid in patients with essential tremor
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): Hongmei Cao, Johanna Thompson-Westra, Mark Hallett, Dietrich Haubenberger
ObjectiveTo investigate the effect of octanoic acid (OA) on the peripheral component of tremor, as well as OA's differential effects on the central and peripheral tremor component in essential tremor (ET) patients.MethodsWe analyzed postural tremor accelerometry data from a double-blind placebo-controlled cross-over study evaluating the effect of 4 mg/kg OA in ET. The weighted condition was used to identify tremor power for both the central and peripheral tremor components. Exploratory non-parametric statistical analyses were used to describe the relation between the central and peripheral component of tremor power.ResultsA peripheral tremor component was identified in 4 out of 18 subjects. Tremor power was reduced after OA administration in both the central and the peripheral tremor component. There was a positive correlation of tremor power between the central and peripheral component, both after placebo and OA.ConclusionsWhen present, the peripheral component was closely related to the central tremor component. We hypothesize that the magnitude of the peripheral mechanical component of tremor is determined by that of the central component.SignificanceBoth central and peripheral component of tremor are reduced after OA, with the central component providing the energy driving the peripheral component.
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Excitability of sensory axons in amyotrophic lateral sclerosis
Publication date: July 2018
Source:Clinical Neurophysiology, Volume 129, Issue 7
Author(s): José Manuel Matamala, James Howells, Thanuja Dharmadasa, William Huynh, Susanna B. Park, David Burke, Matthew C. Kiernan
ObjectiveTo evaluate the excitability of sensory axons in patients with amyotrophic lateral sclerosis (ALS).MethodsComprehensive sensory nerve excitability studies were prospectively performed on 28 sporadic ALS patients, compared to age-matched controls. Sensory nerve action potentials were recorded from digit 2 following median nerve stimulation at the wrist. Disease severity was measured using motor unit number estimation (MUNE), the revised ALS Functional Rating Scale (ALSFRS-R) and the MRC scale.ResultsThere were no significant differences in standard and extended measures of nerve excitability between ALS patients and controls. These unchanged excitability measures included accommodation to long-lasting hyperpolarization and the threshold changes after two supramaximal stimuli during the recovery cycle. Excitability parameters did not correlate with MUNE, ALSFRS-R, APB MRC scale or disease duration.ConclusionsThis cross-sectional study has identified normal axonal membrane properties in myelinated sensory axons of ALS patients. Previously described sensory abnormalities could be the result of axonal fallout, possibly due to a ganglionopathy, or to involvement of central sensory pathways rostral to gracile and cuneate nuclei.SignificanceThese results demonstrate the absence of generalized dysfunction of the membrane properties of sensory axons in ALS in the face of substantial deficits in motor function.
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Editorial Board
Source:Journal of Environmental Radioactivity, Volumes 190–191
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Initial data on adsorption of Cs and Sr to the surfaces of microplastics with biofilm
Publication date: October 2018
Source:Journal of Environmental Radioactivity, Volumes 190–191
Author(s): Mathew P. Johansen, Emily Prentice, Tom Cresswell, Nick Howell
The adsorption of radiocesium and radiostrontium onto a range of natural materials has been well quantified, but not for the new media of environmental plastics, which may have enhanced adsorption due to surface-weathering and development of biofilms. Microplastic samples were deployed in freshwater, estuarine and marine conditions, then characterised using infrared spectroscopy to document changes to the plastic surface (vs interior). Synchrotron elemental mapping data revealed surfaces that were well-covered by accumulation of reactive water solutes and sulphur, but, in contrast, had highly discrete coverage of elements such as Fe and Ti, indicating adhered mineral/clay-associated agglomerates that may increase overall adsorption capacity. Plastics that had been deployed for nearly five months adsorbed radionuclides in both freshwater and estuarine conditions with the highest Kd for cesium (Cs) in freshwater (80 ml g−1) and lowest for strontium (Sr) in estuarine conditions (5 ml g−1). The degree of Cs and Sr adsorption onto plastics appears to be approximately 2–3 orders of magnitude lower than for sediment reference values. While lower than for sediments, adsorption occurred on all samples and may indicate a significant radionuclide reservoir, given that plastics are relatively buoyant and mobile in water regimes, and are increasing in global aquatic systems.
Graphical abstract
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A double-tracer radioisotope approach to assess simultaneous bioaccumulation of caesium in the olive flounder Paralichthys olivaceus
Source:Journal of Environmental Radioactivity, Volumes 190–191
Author(s): Roberta L. Hansman, Marc Metian, Simon Pouil, François Oberhänsli, Jean-Louis Teyssié, Peter W. Swarzenski
To better understand bioaccumulation of radiocaesium in the commercially important Japanese flatfish, Paralichthys olivaceus, the uptake and depuration kinetics of caesium via both seawater and food were assessed simultaneously using controlled aquaria. The pre-conditioned fish were exposed to radionuclides via the two different pathways (aqueous versus dietary) concurrently using two isotopes of caesium, 137Cs and 134Cs, respectively. Dissolved caesium uptake was linear and did not reach a steady state over the course of the 8-day exposure period. Consumption of 134Cs-labelled food led to higher bioaccumulation rates of radioactive Cs than via seawater exposure of 137Cs during uptake and following depuration, though the model-derived long-lived biological half-lives of both pathways was approximately 66 d. Further development of this method for assessing multiple radiocaesium bioaccumulation pathways simultaneously could lead to a promising new approach for studying Cs contamination in marine organisms.
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Measurement of ambient dose equivalent rates by walk survey around Fukushima Dai-ichi Nuclear Power Plant using KURAMA-II until 2016
Publication date: October 2018
Source:Journal of Environmental Radioactivity, Volumes 190–191
Author(s): Masaki Andoh, Hideaki Yamamoto, Takashi Kanno, Kimiaki Saito
Ambient dose equivalent rates in various environments related to human lives were measured by walk surveys using the KURAMA-II systems from 2013 to 2016 within an 80-km radius of the Fukushima Dai-ichi Nuclear Power Plant. The dose rate of the locations where the walk survey was performed decreased to about 38% of its initial value in the 42 months from June 2013 to the December 2016, which was beyond that attributable to the physical decay of radiocaesium. The ecological half-life of the slow decreasing component was evaluated to be 4.1 ± 0.2 y. The air dose rates decreased depending on the level of the evacuation areas, and the decrease in the dose rates was slightly larger in populated areas where humans are active. The dose rates as measured by walk surveys exhibited a good correlation with those by car-borne surveys, suggesting that car-borne survey data are reflecting the air dose rates in living environments surrounding roads. The comparison of walk survey data with car-borne survey data indicated that the air dose rate varies largely even within a 100 m square area, and the variation is enhanced by human activities. The dose rates measured by the walk surveys were estimated to be medial of those along roads and those of undisturbed flat ground, and they were found to be decreasing quickly compared with the air dose rate from the flat ground fixed-point measurements.
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Spatial and temporal variation in vertical migration of dissolved 137Cs passed through the litter layer in Fukushima forests
Source:Journal of Environmental Radioactivity, Volume 192
Author(s): Momo Kurihara, Yuichi Onda, Hiroyuki Suzuki, Yuichi Iwasaki, Tetsuo Yasutaka
We examined spatial variation in vertical 137Cs flux from the litter layer using lysimeters combined with copper-substituted Prussian blue in two forests (deciduous broad-leaved and Japanese cedar (Cryptomeria japonica)), approximately 40 km northwest of the Fukushima Daiichi Nuclear power plant. The study ran from August 2016 to February 2017 in three periods; summer (10 Aug–4 Oct), autumn (5 Oct–30 Nov) and winter (1 Dec–27 Feb). Twenty-five and 15 lysimeters were installed in the deciduous broad-leaved and the Japanese cedar sites within 400 and 300 m2 areas with 3–5 m intervals, respectively. The geometric means of the flux in the deciduous broad-leaved site were 0.51, 0.085 and 0.060 kBq/m2/month in summer, autumn and winter periods, respectively. In the Japanese cedar site, the mean fluxes were 0.45, 0.036 and 0.023 kBq/m2/month. The ratio of 137Cs flux during the survey period to litter 137Cs inventory was 6% and 1% on average in the deciduous broad-leaved and Japanese cedar sites, respectively. The 137Cs flux in the summer period was much larger than those in other periods, resulting from higher precipitation in the summer. Our fine scale observation with 5 m interval showed very large spatial variation in the 137Cs flux and the differences between maximum and minimum range from 8 to 104 times, but were mostly 20–25 times. The spatial variations in the 137Cs flux were affected positively by those in the litter 137Cs inventory and negatively by canopy openness.
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Environmental radionuclides as contaminants of HPGe gamma-ray spectrometers: Monte Carlo simulations for Modane underground laboratory
Source:Journal of Environmental Radioactivity, Volumes 190–191
Author(s): R. Breier, V.B. Brudanin, P. Loaiza, F. Piquemal, P.P. Povinec, E. Rukhadze, N. Rukhadze, I. Štekl
The main limitation in the high-sensitive HPGe gamma-ray spectrometry has been the detector background, even for detectors placed deep underground. Environmental radionuclides such as 40K and decay products in the 238U and 232Th chains have been identified as the most important radioactive contaminants of construction parts of HPGe gamma-ray spectrometers. Monte Carlo simulations have shown that the massive inner and outer lead shields have been the main contributors to the HPGe-detector background, followed by aluminum cryostat, copper cold finger, detector holder and the lead ring with FET. The Monte Carlo simulated cosmic-ray background gamma-ray spectrum has been by about three orders of magnitude lower than the experimental spectrum measured in the Modane underground laboratory (4800 m w.e.), underlying the importance of using radiopure materials for the construction of ultra-low-level HPGe gamma-ray spectrometers.
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Development and assessment of a simple ecological model (TRIPS) for forests contaminated by radiocesium fallout
Source:Journal of Environmental Radioactivity, Volumes 190–191
Author(s): Yves Thiry, Achim Albrecht, Taku Tanaka
The management of vast forested zones contaminated by radiocesium (rCs) following the Chernobyl and Fukushima fallout is of great social and economic concern in affected areas and requires appropriate dynamic models as predictive or questioning tools. Generally, the existing radio-ecological models need less fragmented data and more ecological realism in their quantitative description of the rCs cycling processes. The model TRIPS ("Transfer of Radionuclide In Perennial vegetation Systems") developed in this study privileged an integrated approach which makes the best use of mass balance studies and available explicit experimental data for Scots pine stands. A main challenge was the differentiation and calibration of foliar absorption as well as root uptake in order to well represent the rCs biocycling. The general dynamics of rCs partitioning was simulated with a relatively good precision against an independent series of observed values. In our scenario the rCs biological cycling enters a steady-state about 15 years after the atmospheric deposits. At that time, the simulations showed an equivalent contribution of foliage and root uptake to the tree contamination. But the root uptake seems not sufficient to compensate the activity decline in the tree. The initial foliar uptake and subsequent internal transfers were confirmed to have a great possible impact on the phasing of tree contamination. An extra finding concerns the roots system acting as a buffer in the early period. The TRIPS model is particularly useful in cases where site-specific integrated datasets are available, but it could also be used with adequate caution to generic sites. This development paves the way for simplification or integration of new modules, as well as for a larger number of other applications for the Chernobyl or Fukushima forests once the appropriate data become available. According to the sensitivity analysis that involves in particular reliable estimates of net foliar uptake as well as root uptake not disconnected from rCs exchange reactions in soil.
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Retention of neodymium by dolomite at variable ionic strength as probed by batch and column experiments
Source:Journal of Environmental Radioactivity, Volumes 190–191
Author(s): H.P. Emerson, F. Zengotita, M. Richmann, Y. Katsenovich, D.T. Reed, T.M. Dittrich
The results presented in this paper highlight the complexity of adsorption and incorporation processes of Nd with dolomite and significantly improve upon previous work investigating trivalent actinide and lanthanide interactions with dolomite. Both batch and mini column experiments were conducted at variable ionic strength. These data highlight the strong chemisorption of Nd to the dolomite surface (equilibrium Kd's > 3000 mL/g) and suggest that equilibrium adsorption processes may not be affected by ionic strength based on similar results at 0.1 and 5.0 M ionic strength in column breakthrough and equilibrium batch (>5 days) results. Mini column experiments conducted over approximately one year also represent a significant development in measurement of sorption of Nd in the presence of flow as previous large-scale column experiments did not achieve breakthrough likely due to the high loading capacity of dolomite for Nd (up to 240 μg/g). Batch experiments in the absence of flow show that the rate of Nd removal increases with increasing ionic strength (up to 5.0 M) with greater removal at greater ionic strength for a 24 h sampling point. We suggest that the increasing ionic strength induces increased mineral dissolution and re-precipitation caused by changes in activity with ionic strength that lead to increased removal of Nd through co-precipitation processes.
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Transfer of radionuclides and dose assessment to ants and anthills in a Swedish forest ecosystem
Source:Journal of Environmental Radioactivity, Volumes 190–191
Author(s): K. Rosén, L. Lenoir, K. Stark, M. Vinichuk, S. Sundell-Bergman
In forest ecosystems soil organisms are important for immobilization, translocation and recycling of radionuclides. Still, there is a lack of studies on the role of insects such as ants in the turnover of radionuclides and how radioactivity affects an ant community. In this study seven anthills were sampled in an area that was heavily contaminated after the fallout from the Chernobyl accident. Samples of ant and anthill materials were taken from different depths of the anthills as well as from the surrounding soil and the activity concentrations of 137Cs were determined. In addition, a radiation dose assessment was performed for ants and anthills using the ERICA tool. The deposition of 137Cs in 1986 in the study area was calculated back to be on average 110,500 Bq m−2. The averaged data for all the seven locations investigated indicate that the level of 137Cs activity concentrations in the anthill's material increased with depth of the anthill being highest at the depth 50–65 cm. The concentration in the upper layers (0–2 cm) and of the ants showed significant correlations with the deposition upon multivariate analysis.The concentration ratio (CR) defined as the ratio between the mass activity for 137Cs density in ants (Bq kg−1 d.w.) and mass activity density in soil (Bq kg−1 d.w.) was determined to be in the range of 0.04–0.14.Also, the transfer factor (TF) defined as the ratio between the mass activity for 137Cs density in ant (Bq kg−1 d.w.) and to the unit area activity density (in Bq m−2 d.w.) was determined for 137Cs to be 0.0015 m2 kg−1 d.w. The assessed radiation doses were found to be a 4.9 μGy h−1 which is below international reference levels for non-human biota.
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18 years of continuous observation of tritium and atmospheric precipitations in Ramnicu Valcea (Romania): A time series analysis
Source:Journal of Environmental Radioactivity, Volumes 190–191
Author(s): Octavian G. Duliu, Carmen Varlam, Muataz Dheyaa Shnawaw
To get more information on the origin of tritium and to evidence any possible presence of anthropogenic sources, between January 1999 and December 2016, the precipitation level and tritium concentration were monthly recorded and investigated by the Cryogenic Institute of Ramnicu Valcea, Romania. Compared with similar data covering a radius of about 1200 km westward, the measurements gave similar results concerning the time evolution of tritium content and precipitation level for the entire time interval excepting the period between 2009 and 2011 when the tritium concentrations showed a slight increase, most probable due to the activity of neighboring experimental pilot plant for tritium and deuterium separation. Regardless this fact, all data pointed towards a steady tendency of tritium concentrations to decrease with an annual rate of about 1.4 ± 0.05%. The experimental data on precipitation levels and tritium concentrations form two complete time series whose time series analysis showed, at p < 0.01, the presence of a single one-year periodicity whose coincident maximums which correspond to late spring - early summer months suggest the existence of the Spring Leak mechanism with a possible contribution of the soil moisture remobilization during the warm period.
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Activity concentrations of 238U and 226Ra in two European black shales and their experimentally-derived leachates
Source:Journal of Environmental Radioactivity, Volumes 190–191
Author(s): Franziska D.H. Wilke, Georg Schettler, Andrea Vieth-Hillebrand, Michael Kühn, Heike Rothe
The production of gas from unconventional resources became an important position in the world energy economics. In 2012, the European Commission's Joint Research Centre estimate 16 trillion cubic meters (Tcm) of technically recoverable shale gas in Europe. Taking into account that the exploitation of unconventional gas can be accompanied by serious health risks due to the release of toxic chemical components and natural occurring radionuclides into the return flow water and their near-surface accumulation in secondary precipitates, we investigated the release of U, Th and Ra from black shales by interaction with drilling fluids containing additives that are commonly employed for shale gas exploitation.We performed leaching tests at elevated temperatures and pressures with an Alum black shale from Bornholm, Denmark and a Posidonia black shale from Lower Saxony, Germany. The Alum shale is a carbonate free black shale with pyrite and barite, containing 74.4 μg/g U. The Posidonia shales is a calcareous shale with pyrite but without detectable amounts of barite containing 3.6 μg/g U.Pyrite oxidized during the tests forming sulfuric acid which lowered the pH on values between 2 and 3 of the extraction fluid from the Alum shale favoring a release of U from the Alum shale to the fluid during the short-term and in the beginning of the long-term experiments. The activity concentration of 238U is as high as 23.9 mBq/ml in the fluid for those experiments. The release of U and Th into the fluid is almost independent of pressure. The amount of uranium in the European shales is similar to that of the Marcellus Shale in the United States but the daughter product of 238U, the 226Ra activity concentrations in the experimentally derived leachates from the European shales are quite low in comparison to that found in industrially derived flowback fluids from the Marcellus shale. This difference could mainly be due to missing Cl in the reaction fluid used in our experiments and a lower fluid to solid ratio in the industrial plays than in the experiments due to subsequent fracking and minute cracks from which Ra can easily be released.
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Sedation for gastrointestinal endoscopy in Australia: what is the same and what is different?
Purpose of review The purpose of this article is to review the practice of sedation for adults having gastrointestinal endoscopy in Australia and to compare it with practice in other countries. Recent findings The practice of sedation for endoscopy in Australia is dominated by anaesthesiologists, who have a preference for deep propofol-based sedation. The recent literature includes a number of guidelines for sedation developed by multidisciplinary groups, anaesthesiologists and gastroenterologists in Australia and other countries. The appropriate health practitioner to provide deep sedation and general anaesthesia, to use propofol for sedation and to manage higher risk patients remains controversial. The estimated risks associated with endoscopy vary by provider, sedation technique and study design (prospective or retrospective, single- or multicentre). New airway management techniques are being investigated that may be useful in patients at high risk of hypoventilation and hypoxia. Summary Endoscopy sedation is safe but more high-quality, multicentre observer-blinded randomized controlled trials are required. Correspondence to Kate Leslie, AO, FAHMS, Department of Anaesthesia and Pain Management, Royal Melbourne Hospital, Parkville, VIC 3050, Australia. Tel: +61 3 93427540; e-mail: kate.leslie@mh.org.au Copyright © 2018 YEAR Wolters Kluwer Health, Inc. All rights reserved.
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Measuring quality of recovery in perioperative clinical trials
Purpose of review Perioperative studies increasingly report patient-centered outcomes, but few provide a valid, global measure of a patient's health status after surgery and anesthesia. This review considers three quality of recovery (QoR) scales. Recent findings The 9-item (QoR Score), 15-item (QoR-15), and 40-item (QoR-40) QoR scales have been extensively validated in perioperative settings, and have also been used as outcome measures in numerous surgery and anesthesia studies. A range of clinical trials are presented to illustrate the value of the QoR scales in perioperative medicine research. Summary The QoR Score, QoR-15, and QoR-40 are valid and recommended endpoints for perioperative clinical trials, and there is guidance as to what constitutes a minimal clinically important difference. These recovery scales are sensitive to a change in health status and, as numerical data, optimize statistical power when used in the design of a clinical trial. They are closely correlated with conventional measures of outcome such as analgesic consumption, pain scores, nausea and vomiting, and hospital stay. Although conventional measures may be considered patient-centered, each are incomplete by themselves. QoR scores provide a meaningful overall evaluation of a patient's recovery after surgery and anesthesia. Correspondence to Paul S. Myles, Department of Anaesthesia and Perioperative Medicine, Alfred Hospital, Commercial Road, Melbourne 3004, VIC, Australia. Tel: +61 39076 2000; fax: +61 39076 2813; e-mail: p.myles@alfred.org.au Copyright © 2018 YEAR Wolters Kluwer Health, Inc. All rights reserved.
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SOCIO-ECOLOGICAL CORRELATES OF EXERCISE AT CARDIAC REHABILITATION COMPLETION
Objectives To describe: (1) the amount of physical activity (PA) in cardiac rehabilitation (CR) graduates by sex, and (2) the correlates of their PA. Design Secondary analysis of baseline data from a randomized trial was undertaken. Graduates were recruited from 3 CR programs. Participants completed a questionnaire which assessed constructs from the Socio-ecological model (i.e., individual-level, social and physical-environmental levels). PA was measured objectively using an ActiGraph GT3X accelerometer. Multi-level modeling was performed. Results 255 patients consented, of which 200 (78.4%) completed the survey and provided valid accelerometer data. Participants self-reported engaging in a mean of 184.51±129.10 (standard deviation) minutes of moderate-to-vigorous-intensity PA (MVPA) per week (with men engaging in more than women, p<.05 accelerometer data revealed participants engaged in minutes of mvpa with meeting recommendations. the mixed models socio-ecological correlate significantly related to greater self-reported was self-regulation accelerometer-derived neighborhood aesthetics conclusions approximately one-quarter cr program completers are achieving recommendations although two-thirds perceive they are. programs should exploit accelerometry and promote skills namely self-monitoring goal-setting positive reinforcement time management relapse prevention. patients be encouraged exercise pleasing locations. funding: this work supported by a grant-in-aid from heart stroke foundation canada ontario award number: prof. grace her toronto general western hospital peter munk cardiac centre university health network. stephanie prince is funded fellowship canadian institute research an endowed strategic ottawa foundation. funders played no role design study collection analysis or interpretation writing manuscript. conflict interest: authors declare that have interest. statement human rights: has been approved appropriate institutional national ethics committee performed accordance ethical standards as laid down declaration helsinki its later amendments comparable standards. on welfare animals: article does not contain any studies animals authors. informed consent: consent obtained all individual corresponding author: sherry l. phd. school kinesiology science bethune york keele street m3j ip3 canada. email: sgrace copyright wolters kluwer inc. rights reserved.>
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Pronator Syndrome: An Uncommon Median Nerve Entrapment Syndrome
Not Applicable for Visual Vignette Correspondence: Ying Liang LOW, National University Hospital, 5 Lower Kent Ridge Road, Singapore 119074, Email: ying_liang_low@nuhs.edu.sg Author Disclosures: There are no competing interests; no funding, grants or equipment provided for the project from any source; and no financial benefits to the authors. This article has not been presented in any form previously. Copyright © 2018 Wolters Kluwer Health, Inc. All rights reserved.
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Genetic structure analysis of mantis shrimp Oratosquilla oratoria based on mitochondrial DNA control region sequence
Abstract
The genetic relationships of mantis shrimp Oratosquilla oratoria between the coastal waters of China and Japan were not well studied. To reveal the genetic differentiation and genetic structure among populations, we collected populations of mantis shrimp O. oratoria from the coastal waters of China and Japan to analyze the mtDNA control region variation. A total of 309 individuals of O. oratoria were collected from 13 localities (11 from China and 2 from Japan) and a segment of mitochondrial DNA control region was sequenced. Three hundred nine haplotypes were defined, yielding a very high haplotype diversity and nucleotide diversity. Two lineages of O. oratoria were revealed and displayed strong differences in the geographical distribution. In the coastal waters of China, the geographic distribution of the two lineages was completely separated by the Yangtze River estuary; however, the lineages showed geographic sympatry in two populations from Japan. Based on the lineage distribution, three groups were defined. There was no significant genetic differentiation among the populations within the three groups, indicating high gene flow within each group. Significant and negative values for Tajima D and Fu's Fs tests, and mismatch distributions for two lineages indicated population expansion. The present result confirmed that the freshwater outflow from the Yangtze River formed a physical barrier and affected gene exchange. The different distribution patterns of the two lineages in coastal waters of China and Japan indicated that the larvae of O. oratoria were transferred from China to the coastal waters of Japan with a one-way gene flow.
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