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Adair Smith G, Dunlop A, Alexander SE, Barnes H, Casey F, Chick J, Gunapala R, Herbert T, Lawes R, Mason SA, Mitchell A, Mohajer J, Murray J, Nill S, Patel P, Pathmanathan A, Sritharan K, Sundahl N, Tree AC, Westley R, Williams B, McNair HA. Evaluation of therapeutic radiographer contouring for magnetic resonance image guided online adaptive prostate radiotherapy. Radiother Oncol 2023; 180:109457. [PMID: 36608770 PMCID: PMC10074473 DOI: 10.1016/j.radonc.2022.109457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 12/13/2022] [Accepted: 12/23/2022] [Indexed: 01/05/2023]
Abstract
BACKGROUND AND PURPOSE The implementation of MRI-guided online adaptive radiotherapy has facilitated the extension of therapeutic radiographers' roles to include contouring, thus releasing the clinician from attending daily treatment. Following undergoing a specifically designed training programme, an online interobserver variability study was performed. MATERIALS AND METHODS 117 images from six patients treated on a MR Linac were contoured online by either radiographer or clinician and the same images contoured offline by the alternate profession. Dice similarity coefficient (DSC), mean distance to agreement (MDA), Hausdorff distance (HD) and volume metrics were used to analyse contours. Additionally, the online radiographer contours and optimised plans (n = 59) were analysed using the offline clinician defined contours. After clinical implementation of radiographer contouring, target volume comparison and dose analysis was performed on 20 contours from five patients. RESULTS Comparison of the radiographers' and clinicians' contours resulted in a median (range) DSC of 0.92 (0.86 - 0.99), median (range) MDA of 0.98 mm (0.2-1.7) and median (range) HD of 6.3 mm (2.5-11.5) for all 117 fractions. There was no significant difference in volume size between the two groups. Of the 59 plans created with radiographer online contours and overlaid with clinicians' offline contours, 39 met mandatory dose constraints and 12 were acceptable because 95 % of the high dose PTV was covered by 95 % dose, or the high dose PTV was within 3 % of online plan. A clinician blindly reviewed the eight remaining fractions and, using trial quality assurance metrics, deemed all to be acceptable. Following clinical implementation of radiographer contouring, the median (range) DSC of CTV was 0.93 (0.88-1.0), median (range) MDA was 0.8 mm (0.04-1.18) and HD was 5.15 mm (2.09-8.54) respectively. Of the 20 plans created using radiographer online contours overlaid with clinicians' offline contours, 18 met the dosimetric success criteria, the remaining 2 were deemed acceptable by a clinician. CONCLUSION Radiographer and clinician prostate and seminal vesicle contours on MRI for an online adaptive workflow are comparable and produce clinically acceptable plans. Radiographer contouring for prostate treatment on a MR-linac can be effectively introduced with appropriate training and evaluation. A DSC threshold for target structures could be implemented to streamline future training.
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Affiliation(s)
| | - Alex Dunlop
- Joint Department of Physics at the Royal Marsden and The Institute of Cancer Research, United Kingdom
| | - Sophie E Alexander
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Helen Barnes
- The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Francis Casey
- Joint Department of Physics at the Royal Marsden and The Institute of Cancer Research, United Kingdom
| | - Joan Chick
- Joint Department of Physics at the Royal Marsden and The Institute of Cancer Research, United Kingdom
| | - Ranga Gunapala
- Clinical Trials and Statistic Unit, The Institute for Cancer Research, London, United Kingdom
| | - Trina Herbert
- The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Rebekah Lawes
- The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Sarah A Mason
- Joint Department of Physics at the Royal Marsden and The Institute of Cancer Research, United Kingdom
| | - Adam Mitchell
- Joint Department of Physics at the Royal Marsden and The Institute of Cancer Research, United Kingdom
| | - Jonathan Mohajer
- Joint Department of Physics at the Royal Marsden and The Institute of Cancer Research, United Kingdom
| | - Julia Murray
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Simeon Nill
- Joint Department of Physics at the Royal Marsden and The Institute of Cancer Research, United Kingdom
| | - Priyanka Patel
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Angela Pathmanathan
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Kobika Sritharan
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Nora Sundahl
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Alison C Tree
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Rosalyne Westley
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | | | - Helen A McNair
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
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Adair Smith G, Dunlop A, Alexander SE, Barnes H, Casey F, Chick J, Gunapala R, Herbert T, Lawes R, Mason SA, Mitchell A, Mohajer J, Murray J, Nill S, Patel P, Pathmanathan A, Sritharan K, Sundahl N, Westley R, Tree AC, McNair HA. Interobserver variation of clinical oncologists compared to therapeutic radiographers (RTT) prostate contours on T2 weighted MRI. Tech Innov Patient Support Radiat Oncol 2023; 25:100200. [PMID: 36654720 PMCID: PMC9841345 DOI: 10.1016/j.tipsro.2022.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 11/22/2022] [Accepted: 12/21/2022] [Indexed: 01/01/2023] Open
Abstract
The implementation of MRI-guided online adaptive radiotherapy has enabled extension of therapeutic radiographers' roles to include contouring. An offline interobserver variability study compared five radiographers' and five clinicians' contours on 10 MRIs acquired on a MR-Linac from 10 patients. All contours were compared to a "gold standard" created from an average of clinicians' contours. The median (range) DSC of radiographers' and clinicians' contours compared to the "gold standard" was 0.91 (0.86-0.96), and 0.93 (0.88-0.97) respectively illustrating non-inferiority of the radiographers' contours to the clinicians. There was no significant difference in HD, MDA or volume size between the groups.
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Affiliation(s)
| | - Alex Dunlop
- Joint Department of Physics at the Royal Marsden and The Institute of Cancer Research, United Kingdom
| | - Sophie E. Alexander
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Helen Barnes
- The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Francis Casey
- Joint Department of Physics at the Royal Marsden and The Institute of Cancer Research, United Kingdom
| | - Joan Chick
- Joint Department of Physics at the Royal Marsden and The Institute of Cancer Research, United Kingdom
| | - Ranga Gunapala
- Clinical Trials and Statistic Unit, The Institute for Cancer Research, London, United Kingdom
| | - Trina Herbert
- The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Rebekah Lawes
- The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Sarah A. Mason
- Joint Department of Physics at the Royal Marsden and The Institute of Cancer Research, United Kingdom
| | - Adam Mitchell
- Joint Department of Physics at the Royal Marsden and The Institute of Cancer Research, United Kingdom
| | - Jonathan Mohajer
- Joint Department of Physics at the Royal Marsden and The Institute of Cancer Research, United Kingdom
| | - Julia Murray
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Simeon Nill
- Joint Department of Physics at the Royal Marsden and The Institute of Cancer Research, United Kingdom
| | - Priyanka Patel
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Angela Pathmanathan
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Kobika Sritharan
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Nora Sundahl
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Rosalyne Westley
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Alison C. Tree
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Helen A. McNair
- The Institute of Cancer Research/The Royal Marsden NHS Foundation Trust, London, United Kingdom
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Mason SA, Al Saikhan L, Jones S, James SN, Murray-Smith H, Rapala A, Williams S, Sudre C, Wong B, Richards M, Fox NC, Hardy R, Schott JM, Chaturvedi N, Hughes AD. Association between carotid atherosclerosis and brain activation patterns during the Stroop task in older adults: An fNIRS investigation. Neuroimage 2022; 257:119302. [PMID: 35595200 PMCID: PMC10466022 DOI: 10.1016/j.neuroimage.2022.119302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 05/07/2022] [Accepted: 05/09/2022] [Indexed: 11/17/2022] Open
Abstract
There is an increasing body of evidence suggesting that vascular disease could contribute to cognitive decline and overt dementia. Of particular interest is atherosclerosis, as it is not only associated with dementia, but could be a potential mechanism through which cardiovascular disease directly impacts brain health. In this work, we evaluated the differences in functional near infrared spectroscopy (fNIRS)-based measures of brain activation, task performance, and the change in central hemodynamics (mean arterial pressure (MAP) and heart rate (HR)) during a Stroop color-word task in individuals with atherosclerosis, defined as bilateral carotid plaques (n = 33) and healthy age-matched controls (n = 33). In the healthy control group, the left prefrontal cortex (LPFC) was the only region showing evidence of activation when comparing the incongruous with the nominal Stroop test. A smaller extent of brain activation was observed in the Plaque group compared with the healthy controls (1) globally, as measured by oxygenated hemoglobin (p = 0.036) and (2) in the LPFC (p = 0.02) and left sensorimotor cortices (LMC)(p = 0.008) as measured by deoxygenated hemoglobin. There were no significant differences in HR, MAP, or task performance (both in terms of the time required to complete the task and number of errors made) between Plaque and control groups. These results suggest that carotid atherosclerosis is associated with altered functional brain activation patterns despite no evidence of impaired performance of the Stroop task or central hemodynamic changes.
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Affiliation(s)
- Sarah A Mason
- MRC Unit for Lifelong Health and Ageing at University College London, Department of Population Science and Experimental Medicine, Institute of Cardiovascular Science, 1-19 Torrington Place, London, WC1E 7HB, United Kingdom.
| | - Lamia Al Saikhan
- Department of Cardiac Technology, College of Applied Medical Sciences, Imam Abdulrahman Bin Faisal University, 2835 King Faisal Street, Damman, Kingdom of Saudi Arabia
| | - Siana Jones
- MRC Unit for Lifelong Health and Ageing at University College London, Department of Population Science and Experimental Medicine, Institute of Cardiovascular Science, 1-19 Torrington Place, London, WC1E 7HB, United Kingdom
| | - Sarah-Naomi James
- MRC Unit for Lifelong Health and Ageing at University College London, Department of Population Science and Experimental Medicine, Institute of Cardiovascular Science, 1-19 Torrington Place, London, WC1E 7HB, United Kingdom; Dementia Research Centre, Institute of Neurology, University College London, London, UK
| | - Heidi Murray-Smith
- Centre for Medical Image Computing, Department of Computer Science, University College London, London UK
| | - Alicja Rapala
- MRC Unit for Lifelong Health and Ageing at University College London, Department of Population Science and Experimental Medicine, Institute of Cardiovascular Science, 1-19 Torrington Place, London, WC1E 7HB, United Kingdom
| | - Suzanne Williams
- MRC Unit for Lifelong Health and Ageing at University College London, Department of Population Science and Experimental Medicine, Institute of Cardiovascular Science, 1-19 Torrington Place, London, WC1E 7HB, United Kingdom
| | - Carole Sudre
- MRC Unit for Lifelong Health and Ageing at University College London, Department of Population Science and Experimental Medicine, Institute of Cardiovascular Science, 1-19 Torrington Place, London, WC1E 7HB, United Kingdom; Centre for Medical Image Computing, Department of Computer Science, University College London, London UK; School of Biomedical Engineering, King's College, London UK
| | - Brian Wong
- MRC Unit for Lifelong Health and Ageing at University College London, Department of Population Science and Experimental Medicine, Institute of Cardiovascular Science, 1-19 Torrington Place, London, WC1E 7HB, United Kingdom
| | - Marcus Richards
- MRC Unit for Lifelong Health and Ageing at University College London, Department of Population Science and Experimental Medicine, Institute of Cardiovascular Science, 1-19 Torrington Place, London, WC1E 7HB, United Kingdom
| | - Nick C Fox
- Dementia Research Centre, Institute of Neurology, University College London, London, UK
| | - Rebecca Hardy
- MRC Unit for Lifelong Health and Ageing at University College London, Department of Population Science and Experimental Medicine, Institute of Cardiovascular Science, 1-19 Torrington Place, London, WC1E 7HB, United Kingdom
| | - Jonathan M Schott
- MRC Unit for Lifelong Health and Ageing at University College London, Department of Population Science and Experimental Medicine, Institute of Cardiovascular Science, 1-19 Torrington Place, London, WC1E 7HB, United Kingdom; Centre for Medical Image Computing, Department of Computer Science, University College London, London UK
| | - Nish Chaturvedi
- MRC Unit for Lifelong Health and Ageing at University College London, Department of Population Science and Experimental Medicine, Institute of Cardiovascular Science, 1-19 Torrington Place, London, WC1E 7HB, United Kingdom
| | - Alun D Hughes
- MRC Unit for Lifelong Health and Ageing at University College London, Department of Population Science and Experimental Medicine, Institute of Cardiovascular Science, 1-19 Torrington Place, London, WC1E 7HB, United Kingdom.
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Mason SA, White IM, Lalondrelle S, Bamber JC, Harris EJ. The Stacked-Ellipse Algorithm: An Ultrasound-Based 3-D Uterine Segmentation Tool for Enabling Adaptive Radiotherapy for Uterine Cervix Cancer. Ultrasound Med Biol 2020; 46:1040-1052. [PMID: 31926750 PMCID: PMC7043010 DOI: 10.1016/j.ultrasmedbio.2019.09.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/28/2019] [Revised: 08/30/2019] [Accepted: 09/04/2019] [Indexed: 06/10/2023]
Abstract
The stacked-ellipse (SE) algorithm was developed to rapidly segment the uterus on 3-D ultrasound (US) for the purpose of enabling US-guided adaptive radiotherapy (RT) for uterine cervix cancer patients. The algorithm was initialised manually on a single sagittal slice to provide a series of elliptical initialisation contours in semi-axial planes along the uterus. The elliptical initialisation contours were deformed according to US features such that they conformed to the uterine boundary. The uterus of 15 patients was scanned with 3-D US using the Clarity System (Elekta Ltd.) at multiple days during RT and manually contoured (n = 49 images and corresponding contours). The median (interquartile range) Dice similarity coefficient and mean surface-to-surface-distance between the SE algorithm and manual contours were 0.80 (0.03) and 3.3 (0.2) mm, respectively, which are within the ranges of reported inter-observer contouring variabilities. The SE algorithm could be implemented in adaptive RT to precisely segment the uterus on 3-D US.
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Affiliation(s)
- Sarah A Mason
- Joint Department of Physics, Institute of Cancer Research, London, United Kingdom
| | - Ingrid M White
- Radiotherapy Department, Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Susan Lalondrelle
- Radiotherapy Department, Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Jeffrey C Bamber
- Joint Department of Physics, Institute of Cancer Research, London, United Kingdom
| | - Emma J Harris
- Joint Department of Physics, Institute of Cancer Research, London, United Kingdom.
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Mason SA, White IM, O'Shea T, McNair HA, Alexander S, Kalaitzaki E, Bamber JC, Harris EJ, Lalondrelle S. Combined Ultrasound and Cone Beam CT Improves Target Segmentation for Image Guided Radiation Therapy in Uterine Cervix Cancer. Int J Radiat Oncol Biol Phys 2019; 104:685-693. [PMID: 30872145 PMCID: PMC6542416 DOI: 10.1016/j.ijrobp.2019.03.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 02/07/2019] [Accepted: 03/03/2019] [Indexed: 12/14/2022]
Abstract
PURPOSE Adaptive radiation therapy strategies could account for interfractional uterine motion observed in patients with cervix cancer, but the current cone beam computed tomography (CBCT)-based treatment workflow is limited by poor soft-tissue contrast. The goal of the present study was to determine if ultrasound (US) could be used to improve visualization of the uterus, either as a single modality or in combination with CBCT. METHODS AND MATERIALS Interobserver uterine contour agreement and confidence were compared on 40 corresponding CBCT, US, and CBCT-US-fused images from 11 patients with cervix cancer. Contour agreement was measured using the Dice similarity coefficient (DSC) and mean contour-to-contour distance (MCCD). Observers rated their contour confidence on a scale from 1 to 10. Pairwise Wilcoxon signed-rank tests were used to measure differences in contour agreement and confidence. RESULTS CBCT-US fused images had significantly better contour agreement and confidence than either individual modality (P < .05), with median (interquartile range [IQR]) values of 0.84 (0.11), 1.26 (0.23) mm, and 7 (2) for the DSC, MCCD, and observer confidence ratings, respectively. Contour agreement was similar between US and CBCT, with median (IQR) DSCs of 0.81 (0.17) and 0.82 (0.14) and MCCDs of 1.75 (1.15) mm and 1.62 (0.74) mm. Observers were significantly more confident in their US-based contours than in their CBCT-based contours (P < .05), with median (IQR) confidence ratings of 7 (2.75) versus 5 (4). CONCLUSIONS CBCT and US are complementary and improve uterine segmentation precision when combined. Observers could localize the uterus with a similar precision on independent US and CBCT images.
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Affiliation(s)
- Sarah A Mason
- Institute of Cancer Research, Radiotherapy and Imaging, London, United Kingdom
| | - Ingrid M White
- Radiotherapy Department, Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Tuathan O'Shea
- Radiotherapy Physics Department, Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Helen A McNair
- Radiotherapy Department, Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Sophie Alexander
- Radiotherapy Department, Royal Marsden NHS Foundation Trust, London, United Kingdom
| | | | - Jeffrey C Bamber
- Institute of Cancer Research, Radiotherapy and Imaging, London, United Kingdom
| | - Emma J Harris
- Institute of Cancer Research, Radiotherapy and Imaging, London, United Kingdom.
| | - Susan Lalondrelle
- Radiotherapy Department, Royal Marsden NHS Foundation Trust, London, United Kingdom
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McNeish RE, Kim LH, Barrett HA, Mason SA, Kelly JJ, Hoellein TJ. Microplastic in riverine fish is connected to species traits. Sci Rep 2018; 8:11639. [PMID: 30076314 PMCID: PMC6076259 DOI: 10.1038/s41598-018-29980-9] [Citation(s) in RCA: 125] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 07/23/2018] [Indexed: 11/09/2022] Open
Abstract
Microplastic is a contaminant of concern worldwide. Rivers are implicated as major pathways of microplastic transport to marine and lake ecosystems, and microplastic ingestion by freshwater biota is a risk associated with microplastic contamination, but there is little research on microplastic ecology within freshwater ecosystems. Microplastic uptake by fish is likely affected by environmental microplastic abundance and aspects of fish ecology, but these relationships have rarely been addressed. We measured the abundance and composition of microplastic in fish and surface waters from 3 major tributaries of Lake Michigan, USA. Microplastic was detected in fish and surface waters from all 3 sites, but there was no correlation between microplastic concentrations in fish and surface waters. Rather, there was a significant effect of functional feeding group on microplastic concentration in fish. Neogobius melanostomus (round goby, a zoobenthivore) had the highest concentration of gut microplastic (19 particles fish-1) compared to 10 other fish taxa measured, and had a positive linear relationship between body size and number of microplastic particles. Surface water microplastic concentrations were lowest in the most northern, forested watershed, and highest in the most southern, agriculturally dominated watershed. Results suggest microplastic pollution is common in river food webs and is connected to species feeding characteristics. Future research should focus on understanding the movement of microplastic from point-source and diffuse sources and into aquatic ecosystems, which will support pollution management efforts on inland waters.
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Affiliation(s)
- R E McNeish
- Loyola University Chicago - Biology, 1032 West Sheridan Road, Chicago, IL, 60660, USA.
| | - L H Kim
- Loyola University Chicago - Biology, 1032 West Sheridan Road, Chicago, IL, 60660, USA
| | - H A Barrett
- Department of Geology and Environmental Sciences, The State University of New York at Fredonia, 280 Central Ave., Science Complex 340, Fredonia, NY, 14063, USA
| | - S A Mason
- Department of Geology and Environmental Sciences, The State University of New York at Fredonia, 280 Central Ave., Science Complex 340, Fredonia, NY, 14063, USA
| | - J J Kelly
- Loyola University Chicago - Biology, 1032 West Sheridan Road, Chicago, IL, 60660, USA
| | - T J Hoellein
- Loyola University Chicago - Biology, 1032 West Sheridan Road, Chicago, IL, 60660, USA
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Mason SA, O’Shea TP, White IM, Lalondrelle S, Downey K, Baker M, Behrens CF, Bamber JC, Harris EJ. Towards ultrasound-guided adaptive radiotherapy for cervical cancer: Evaluation of Elekta's semiautomated uterine segmentation method on 3D ultrasound images. Med Phys 2017; 44:3630-3638. [PMID: 28493295 PMCID: PMC5575494 DOI: 10.1002/mp.12325] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 02/10/2017] [Accepted: 03/29/2017] [Indexed: 11/06/2022] Open
Abstract
PURPOSE 3D ultrasound (US) images of the uterus may be used to adapt radiotherapy (RT) for cervical cancer patients based on changes in daily anatomy. This requires accurate on-line segmentation of the uterus. The aim of this work was to assess the accuracy of Elekta's "Assisted Gyne Segmentation" (AGS) algorithm in semi-automatically segmenting the uterus on 3D transabdominal ultrasound images by comparison with manual contours. MATERIALS & METHODS Nine patients receiving RT for cervical cancer were imaged with the 3D Clarity® transabdominal probe at RT planning, and 1 to 7 times during treatment. Image quality was rated from unusable (0)-excellent (3). Four experts segmented the uterus (defined as the uterine body and cervix) manually and using AGS on images with a ranking > 0. Pairwise analysis between manual contours was evaluated to determine interobserver variability. The accuracy of the AGS method was assessed by measuring its agreement with manual contours via pairwise analysis. RESULTS 35/44 images acquired (79.5%) received a ranking > 0. For the manual contour variation, the median [interquartile range (IQR)] distance between centroids (DC) was 5.41 [5.0] mm, the Dice similarity coefficient (DSC) was 0.78 [0.11], the mean surface-to-surface distance (MSSD) was 3.20 [1.8] mm, and the uniform margin of 95% (UM95) was 4.04 [5.8] mm. There was no correlation between image quality and manual contour agreement. AGS failed to give a result in 19.3% of cases. For the remaining cases, the level of agreement between AGS contours and manual contours depended on image quality. There were no significant differences between the AGS segmentations and the manual segmentations on the images that received a quality rating of 3. However, the AGS algorithm had significantly worse agreement with manual contours on images with quality ratings of 1 and 2 compared with the corresponding interobserver manual variation. The overall median [IQR] DC, DSC, MSSD, and UM95 between AGS and manual contours was 5.48 [5.45] mm, 0.77 [0.14], 3.62 [2.7] mm, and 5.19 [8.1] mm, respectively. CONCLUSIONS The AGS tool was able to represent uterine shape of cervical cancer patients in agreement with manual contouring in cases where the image quality was excellent, but not in cases where image quality was degraded by common artifacts such as shadowing and signal attenuation. The AGS tool should be used with caution for adaptive RT purposes, as it is not reliable in accurately segmenting the uterus on 'good' or 'poor' quality images. The interobserver agreement between manual contours of the uterus drawn on 3D US was consistent with results of similar studies performed on CT and MRI images.
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Affiliation(s)
- Sarah A. Mason
- Joint Department of Physics at the Institute of Cancer Research and Royal Marsden NHS Foundation TrustSutton and LondonUK
| | - Tuathan P. O’Shea
- Joint Department of Physics at the Institute of Cancer Research and Royal Marsden NHS Foundation TrustSutton and LondonUK
| | - Ingrid M. White
- Joint Department of Physics at the Institute of Cancer Research and Royal Marsden NHS Foundation TrustSutton and LondonUK
| | - Susan Lalondrelle
- Joint Department of Physics at the Institute of Cancer Research and Royal Marsden NHS Foundation TrustSutton and LondonUK
| | - Kate Downey
- Joint Department of Physics at the Institute of Cancer Research and Royal Marsden NHS Foundation TrustSutton and LondonUK
| | - Mariwan Baker
- Department of OncologyHerlev Hospital, University of CopenhagenHerlevDenmark
| | - Claus F. Behrens
- Department of OncologyHerlev Hospital, University of CopenhagenHerlevDenmark
| | - Jeffrey C. Bamber
- Joint Department of Physics at the Institute of Cancer Research and Royal Marsden NHS Foundation TrustSutton and LondonUK
| | - Emma J. Harris
- Joint Department of Physics at the Institute of Cancer Research and Royal Marsden NHS Foundation TrustSutton and LondonUK
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Viero C, Euden J, Mason SA, Seidel MK, Thomas NL, Zissimopoulos S, Williams AJ. P373Two key regions of the human cardiac ryanodine receptor calcium release channel modulate its gating properties in a dual manner. Cardiovasc Res 2014. [DOI: 10.1093/cvr/cvu091.56] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Cuypers MG, Mason SA, Blakeley MP, Mitchell EP, Haertlein M, Forsyth VT. Near-atomic resolution neutron crystallography on perdeuterated Pyrococcus furiosus rubredoxin: implication of hydronium ions and protonation state equilibria in redox changes. Angew Chem Int Ed Engl 2012; 52:1022-5. [PMID: 23225503 DOI: 10.1002/anie.201207071] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Indexed: 11/09/2022]
Affiliation(s)
- M G Cuypers
- EPSAM/ISTM, Keele University, Staffordshire, ST5 5BG, UK
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KilBride AL, Mason SA, Honeyman PC, Pritchard DG, Hepple S, Green LE. Associations between membership of farm assurance and organic certification schemes and compliance with animal welfare legislation. Vet Rec 2011; 170:152. [PMID: 22331783 DOI: 10.1136/vr.100345] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Animal health (AH) defines the outcome of their inspections of livestock holdings as full compliance with the legislation and welfare code (A), compliance with the legislation but not the code (B), non-compliance with legislation but no pain, distress or suffering obvious in the animals (C) or evidence of unnecessary pain or unnecessary distress (D). The aim of the present study was to investigate whether membership of farm assurance or organic certification schemes was associated with compliance with animal welfare legislation as inspected by AH. Participating schemes provided details of their members, past and present, and these records were matched against inspection data from AH. Multivariable multilevel logistic binomial models were built to investigate the association between compliance with legislation and membership of a farm assurance/organic scheme. The percentage of inspections coded A, B, C or D was 37.1, 35.6, 20.2 and 7.1 per cent, respectively. Once adjusted for year, country, enterprise, herd size and reason for inspection, there was a pattern of significantly reduced risk of codes C and D compared with A and B, in certified enterprises compared with the enterprises that were not known to be certified in all species.
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Affiliation(s)
- A L KilBride
- School of Life Sciences, University of Warwick, Coventry CV4 7AL, UK
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Kovalevsky AY, Hanson BL, Mason SA, Yoshida T, Fisher SZ, Mustyakimov M, Forsyth VT, Blakeley MP, Keen DA, Langan P. Identification of the elusive hydronium ion exchanging roles with a proton in an enzyme at lower pH values. Angew Chem Int Ed Engl 2011; 50:7520-3. [PMID: 21604345 DOI: 10.1002/anie.201101753] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Indexed: 11/08/2022]
Affiliation(s)
- Andrey Y Kovalevsky
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87544, USA.
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Amory JR, Barker ZE, Wright JL, Mason SA, Blowey RW, Green LE. Associations between sole ulcer, white line disease and digital dermatitis and the milk yield of 1824 dairy cows on 30 dairy cow farms in England and Wales from February 2003-November 2004. Prev Vet Med 2008; 83:381-91. [PMID: 18031851 DOI: 10.1016/j.prevetmed.2007.09.007] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2006] [Revised: 09/27/2007] [Accepted: 09/28/2007] [Indexed: 10/22/2022]
Abstract
The milk yields of 1824 cows were used to investigate the effect of lesion-specific causes of lameness, based on farmer treatment and diagnosis of lame cows, on milk yield. A three-level hierarchical model of repeated test day yields within cows within herds was used to investigate the impact of lesion-specific causes of lameness (sole ulcer, white line disease, digital dermatitis and other causes) on milk yield before and after treatment compared with unaffected cows. Cattle which developed sole ulcer (SU) and white line disease (WLD) were higher yielding cattle before they were diagnosed. Their milk production fell to below that of the mean of unaffected cows before diagnosis and remained low after diagnosis. In cattle which developed digital dermatitis (DD) there was no significant difference in milk yield before treatment and a slightly raised milk yield immediately after treatment. The estimated milk loss attributable to SU and WLD was approximately 570 and 370 kg, respectively. These results highlight that specific types of lameness vary by herds and within herds they are associated with higher yielding cattle. Consequently lesion-specific lameness reduction programmes targeting the cow and farm specific causes of lameness might be more effective than generic recommendations. They also highlight the importance of milk loss when estimating the economic impact of SU and WLD on the farms profitability.
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Affiliation(s)
- J R Amory
- Ecology and Epidemiology Group, Department of Biological Sciences, University of Warwick, UK.
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13
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Imamura K, Nimz O, Jacob J, Myles D, Mason SA, Kitamura S, Aree T, Saenger W. Hydrogen-bond network in cyclodecaamylose hydrate at 20 K; neutron diffraction study of novel structural motifs band-flip and kink in alpha-(1-->4)-D-glucoside oligosaccharides. Acta Crystallogr B 2001; 57:833-41. [PMID: 11717483 DOI: 10.1107/s0108768101014288] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2001] [Accepted: 08/30/2001] [Indexed: 11/10/2022]
Abstract
A single-crystal neutron diffraction study of cyclodecaamylose (CA10) was carried out at 20 K. CA10 crystallizes with 27.18 water molecules [(C(6)H(10)O(5))(10).27.18H(2)O] in space group C2 with unit-cell constants a = 29.31 (5), b = 9.976 (10), c = 19.34 (2) A, beta = 121.07 (2) degrees. The asymmetric unit contains a half molecule of CA10 and 13.59 water molecules, the other half being related by a crystallographic twofold rotation axis. All H atoms except two water H atoms could be located from difference neutron-density maps; structure refinement converged at R = 0.635. Two of the five CH(2)-O6 groups and one of the 15 O2, O3 hydroxyl groups of CA10 are twofold orientationally disordered. A total of 13.59 water molecules in the asymmetric unit are distributed over 23 positions; 20 of which are in the CA10 cavity, and the other three occupy intermolecular interstices. Of the 123 symmetry-independent hydrogen bonds, 25 (= 20%) are three-centered and 7 (= 6%) are four-centered. Water molecules and O-H groups of CA10 form an extended network with cooperative O-H...O-H...O-H hydrogen bonds. They are arranged in 11 polygons with three, four, five, six and eight O-H bonds and in homodromic, antidromic and heterodromic arrangements. Nine polygons are located within the cavity and the others are outside.
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Affiliation(s)
- K Imamura
- Institut für Kristallographie, Freie Universität Berlin, Takustrasse 6, D-14195 Berlin, Germany
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14
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Scherer W, Sirsch P, Grosche M, Spiegler M, Mason SA, Gardiner MG. Agostic deformations based on electron delocalization in the alkyllithium-complex [{2-(Me3Si)2CLiC5H4N }2Electronic supplementary information (ESI) available: experimental and theoretical details of multipole refinements and model systems. See http://www.rsc.org/suppdata/cc/b1/b105452j/. Chem Commun (Camb) 2001:2072-3. [PMID: 12269281 DOI: 10.1039/b105452j] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Topological analysis of experimental and theoretical charge densities in the title complex [(2-(Me3Si)2CLiC5H4N)2] 1 reveals the nature of the agostic deformation postulated for this complex: delocalization of the Li-C bonding electrons over the entire agostic alkyl group controls the formation of an acute Li-C-Si angle and thus a sufficient electronic saturation of the electron deficient lithium atom via secondary interactions.
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Affiliation(s)
- W Scherer
- Anorganisch-chemisches Institut der Technischen Universität München, Lichtenbergstrasse 4, D-85747 Garching bei München, Germany.
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Ahrens B, Davidson MG, Forsyth VT, Mahon MF, Johnson AL, Mason SA, Price RD, Raithby PR. Neutron diffraction study of a phenol.nitroxide radical adduct: a structural model for hydrogen atom abstraction by peroxyl radicals from vitamin E and related phenolic antioxidants. J Am Chem Soc 2001; 123:9164-5. [PMID: 11552826 DOI: 10.1021/ja015849+] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- B Ahrens
- Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, UK
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16
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Palmer RA, Potter BS, Lisgarten JN, Fenn RH, Mason SA, Mills OS, Robinson PM, Watt CI. X-ray and neutron structure of 1,8-(3,6,9-trioxaundecane-1,11-diyldioxy)-9,10-dihydro-10,10-dimethylanthracene-9-ol (P326); some pitfalls of automatic data collection. Acta Crystallogr B 2001; 57:339-45. [PMID: 11373392 DOI: 10.1107/s0108768100015184] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2000] [Accepted: 10/24/2000] [Indexed: 11/10/2022]
Abstract
The structure of the crown ether 1,8-(3,6,9-trioxaundecane-1,11-diyldioxy)-9,10-dihydro-10,10-dimethylanthracene-9-ol, C(24)H(30)O(6).H(2)O (1), code name P326, the parent compound for a series of derivatives, has been determined by both X-ray diffraction at room temperature and neutron diffraction at very low temperature. The unit cells are very similar at both temperatures and in both cases the crystals exhibit P2(1) symmetry with Z = 4 (two molecules, A and B, respectively, per asymmetric unit) and pseudosymmetry P2(1)/c. The higher symmetry is broken mainly by the two independent water molecules in the unit cell, some reflections which would be absent in P2(1)/c having strong intensities in both the X-ray and neutron data. In both molecules A and B hydrogen bonds involving the water molecule stabilize the macrocyclic ring structure, one involving the macrocyclic O(9) as a donor. Close contacts between the water and macrocyclic O atoms in each molecule also suggest the presence of two bifurcated hydrogen bonds, involving water HW2 to both O(16) and O(18), and water HW1 to both O(18) and O(20), respectively, with considerable variation in the geometry being present. Both molecules A and B exhibit very close pseudosymmetry across a plane perpendicular to the molecular plane and through atoms C(9) and O(18), and in addition are predominantly planar structures. The X-ray analysis failed to reveal one H atom per water molecule, each being subsequently included after location and refinement in the neutron analysis.
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Affiliation(s)
- R A Palmer
- Department of Crystallography, Birkbeck College, London WC1E 7HX, England.
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Fryzuk MD, Johnson SA, Patrick BO, Albinati A, Mason SA, Koetzle TF. New mode of coordination for the dinitrogen ligand: formation, bonding, and reactivity of a tantalum complex with a bridging N(2) unit that is both side-on and end-on. J Am Chem Soc 2001; 123:3960-73. [PMID: 11457146 DOI: 10.1021/ja0041371] [Citation(s) in RCA: 167] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reaction of a mixture of 1 equiv of PhPH(2) and 2 equiv of PhNHSiMe(2)CH(2)Cl with 4 equiv of Bu(n)Li followed by the addition of THF generates the lithiated ligand precursor [NPN]Li(2).(THF)(2) (where [NPN] = PhP(CH(2)SiMe(2)NPh)(2)). The reaction of [NPN]Li(2).(THF)(2) with TaMe(3)Cl(2) produces [NPN]TaMe(3), which reacts under H(2) to yield the diamagnetic dinuclear Ta(IV) tetrahydride ([NPN]Ta)(2)(mu-H)(4). This hydride reacts with N(2) with the loss of H(2) to produce ([NPN]Ta(mu-H))(2)(mu-eta(1):eta(2)-N(2)), which was characterized both in solution and in the solid state, and contains strongly activated N(2) bound in the unprecedented side-on end-on dinuclear bonding mode. A density functional theory calculation on the model complex [(H(3)P)(H(2)N)(2)Ta(mu-H)](2)(mu-eta(1):eta(2)-N(2)) provides insight into the molecular orbital interactions involved in the side-on end-on bonding mode of dinitrogen. The reaction of ([NPN]Ta(mu-H))(2)(mu-eta(1):eta(2)-N(2)) with propene generates the end-on bound dinitrogen complex ([NPN]Ta(CH(2)CH(2)CH(3)))(2)(mu-eta(1):eta(1)-N(2)), and the reaction of [NPN]Li(2).(THF)(2) with NbCl(3)(DME) generates the end-on bound dinitrogen complex ([NPN]NbCl)(2)(mu-eta(1):eta(1)-N(2)). These two end-on bound dinitrogen complexes provide evidence that the bridging hydride ligands are responsible for the unusual bonding mode of dinitrogen in ([NPN]Ta(mu-H))(2)(mu-eta(1):eta(2)-N(2)). The dinitrogen moiety in the side-on end-on mode is amenable to functionalization; the reaction of ([NPN]Ta(mu-H))(2)(mu-eta(1):eta(2)-N(2)) with PhCH(2)Br results in C-N bond formation to yield [NPN]Ta(mu-eta(1):eta(2)-N(2)CH(2)Ph)(mu-H)(2)TaBr[NPN]. Nitrogen-15 NMR spectral data are provided for all the tantalum-dinitrogen complexes and derivatives described.
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Affiliation(s)
- M D Fryzuk
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, B.C., Canada
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Evdokimov A, Gilboa AJ, Koetzle TF, Klooster WT, Schultz AJ, Mason SA, Albinati A, Frolow F. Structures of furanosides: geometrical analysis of low-temperature X-ray and neutron crystal structures of five crystalline methyl pentofuranosides. Acta Crystallogr B 2001; 57:213-20. [PMID: 11262436 DOI: 10.1107/s010876810001661x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2000] [Accepted: 11/08/2000] [Indexed: 11/10/2022]
Abstract
Crystal structures of all five crystalline methyl D-pentofuranosides, methyl alpha-D-arabinofuranoside (1), methyl beta-D-arabinofuranoside (2), methyl alpha-D-lyxofuranoside (3), methyl beta-D-ribofuranoside (4) and methyl alpha-D-xylofuranoside (5) have been determined by means of cryogenic X-ray and neutron crystallography. The neutron diffraction experiments provide accurate, unbiased H-atom positions which are especially important because of the critical role of hydrogen bonding in these systems. This paper summarizes the geometrical and conformational parameters of the structures of all five crystalline methyl pentofuranosides, several of them reported here for the first time. The methyl pentofuranoside structures are compared with the structures of the five crystalline methyl hexopyranosides for which accurate X-ray and neutron structures have been determined. Unlike the methyl hexopyranosides, which crystallize exclusively in the C(1) chair conformation, the five crystalline methyl pentofuranosides represent a very wide range of ring conformations.
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Affiliation(s)
- A Evdokimov
- Protein Engineering Section, Program in Structural Biology, NCI-Frederick Cancer Research and Development Center, PO Box B, Frederick, MD 21702, USA.
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Abstract
BACKGROUND Questions have been asked about whether the process of obtaining informed consent from parents to clinical trials on neonates leads to valid consent. We undertook a study in nine European countries to assess this issue and to seek any practical improvements. METHODS Semi-structured interviews were conducted with parents of 200 babies who had been asked for consent to neonatal trials and 107 neonatologists seeking consent. Analysis assessed the validity of the consent process against four components: parental competence; information given; parental understanding; and voluntariness of consent. FINDINGS 59 of the 200 parents had given valid consent or refusal but the remainder had problems in one or more of the component areas (42 for competence, 43 for information, 44 for understanding, and 21 for voluntariness). The proportions with impaired consent were greatest for research in an emergency situation and for that associated with risk or discomfort greater than standard treatment. Information sheets were little used by parents in deciding whether to consent. Parents highly valued their involvement in the informed consent process, and clinicians generally agreed on the value of the process. INTERPRETATION Current standards of informed consent to neonatal research projects could be improved. Research personnel should receive guidance on legal and ethical constraints governing the process. Oral and written information should be given at the same time. Parents could be made aware that research projects have been examined by research ethics committees. Little support was found for the argument that informed consent should be relinquished for the parents' own good. Further study is needed to identify which elements of the process are valued by parents and clinicians in a process that has some unavoidable limitations.
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Affiliation(s)
- S A Mason
- Northern and Yorkshire Clinical Trials and Research Unit, Leeds, UK.
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Mason SA. Performance-based planning for hospitals. Health Care Strateg Manage 2000; 18:14-7, 1. [PMID: 11125937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
It is time for health care planning to evolve through a new phase--from strategic planning to performance-based planning, writes Scott A. Mason, D.P.A., FACHE, president and CEO of eko systems inc.
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Dawson S, Hickey RG, Mason SA. Grassroots decisionmaking informs care redesign at York Hospital in York, PA. Strateg Healthc Excell 2000; 13:8-11. [PMID: 11009698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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Schneider JJ, Hagen J, Czap N, Kruger C, Mason SA, Bau R, Ensling J, Gutlich P, Wrackmeyer B. Hydroxo hydrido complexes of iron and cobalt (Sn-Fe-Sn, Sn-Co-Sn): probing agostic Sn...H-M interactions in solution and in the solid state. Chemistry 2000; 6:625-35. [PMID: 10807174 DOI: 10.1002/(sici)1521-3765(20000218)6:4<625::aid-chem625>3.0.co;2-i] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Bis(toluene)iron 9 reacts with Lappert's stannylene [Sn[CH(SiMe3)2]2] (4) to form the paramagnetic bis-stannylene complex [[(eta6-toluene)Fe-Sn-[CH(SiMe3)2]2]2] (10). Compound 10 reacts with H2O to form the hydroxo hydrido complex [(eta6-C7H8)(mu-OH)(H)-Fe-[Sn[CH(SiMe3)2]2]2] (12) in high yield; its solid-state structure has been elucidated by X-ray and neutron diffraction analysis. In agreement with the 1H NMR results, 12 contains a hydridic ligand whose exact coordination geometry could be determined by neutron diffraction. The 1H and 119Sn NMR analysis of 12 suggested a multicenter Sn/Sn/H/Fe bonding interaction in solution, based on significantly large values of J(Sn,H,Fe) = 640+/-30 Hz and J(119Sn,119Sn) = 4340+/-100 Hz. In solution, complex 12 exists as two diastereomers in a ratio of about 2:1. Neutron diffraction analysis has characterized 12 as a classical metal hydride complex with very little Sn...H interaction and a typical Fe-H single bond (1.575(8) A). This conclusion is based on the fact that the values of the Sn...H contact distances (2.482(9) and 2.499(9) A) are not consistent with strong Fe-H...Sn interactions. This finding is discussed in relation to other compounds containing M-H...Sn units with and without strong three-center interactions. The neutron diffraction analysis of 12 represents the first determination of a Sn-H atomic distance employing this analytical technique. The cobalt analogues [(eta5-Cp)(mu-OH)(H)Co-[Sn[CH(SiMe3)2]2]2] (15) and [(eta5-Cp)(OD)(D)Co-[Sn[CH-(SiMe3)2]2]2] [D2]15, which are isolobal with 12, were prepared by the reaction of [(eta5-Cp)Co-Sn[CH(SiMe3)2]2] (14) with H2O and D2O, respectively. The magnitude of J(Sn,H) (539 Hz) in 15 is in the same range as that found for 12. The molecular structure of 15 has been determined by X-ray diffraction which reveals it to be isostructural with 12. The coordination geometries of the Co(Fe)-Sn1-O-Sn2 arrangements in 12 and 15 are fully planar within experimental error. Compounds 10 and 15 are rare examples of fully characterized complexes obtained as primary products from water activation reactions.
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Affiliation(s)
- JJ Schneider
- Institut fur Anorganische Chemie der Universitat, Essen, Germany.
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Cade A, Brownlee KG, Conway SP, Haigh D, Short A, Brown J, Dassu D, Mason SA, Phillips A, Eglin R, Graham M, Chetcuti A, Chatrath M, Hudson N, Thomas A, Chetcuti PA. Randomised placebo controlled trial of nebulised corticosteroids in acute respiratory syncytial viral bronchiolitis. Arch Dis Child 2000; 82:126-30. [PMID: 10648365 PMCID: PMC1718208 DOI: 10.1136/adc.82.2.126] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To evaluate short and long term effects of giving nebulised budesonide early in respiratory syncytial viral (RSV) bronchiolitis. DESIGN A multicentre randomised double blind placebo controlled trial. SUBJECTS Infants admitted to hospital with their first episode of RSV positive bronchiolitis. INTERVENTION Randomisation to receive either 1 mg of nebulised budesonide (Bud) or placebo (Pla) twice daily from admission until 2 weeks after discharge. Follow up was for 12 months. MAIN OUTCOME MEASURES Duration of hospital admission, time taken to become symptom free, re-admission rates, general practitioner consultation rates, and use of anti-wheeze medication during follow up. RESULTS 161 infants were studied. Both arms were similar with respect to initial clinical severity, age, sex, socioeconomic class, and tobacco exposure. Median time from first nebulisation to discharge: Bud and Pla, 2 days. Median number of days for 50% of infants to be symptom free for 48 hours: Bud, 10 days; Pla, 12 days. Respiratory re-admission rates in the 12 month follow up: Bud, 16%; Pla, 18%; median difference (95% confidence interval (CI)), -2 (-14 to 10). Median respiratory related general practitioner attendances: Bud, 4.0; Pla, 4.5; median difference (95% CI), -1 (-2 to 0). Percentage of infants receiving at least one prescription for anti-wheeze medication during follow up, corticosteroids: Bud, 50%; Pla, 60%; difference (95% CI), -10 (-26 to 6); bronchodilators: Bud, 60%; Pla, 67%; difference (95% CI), -7 (-22 to 8). CONCLUSIONS There are no short or long term clinical benefits from the administration of nebulised corticosteroids in the acute phase of RSV bronchiolitis.
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Affiliation(s)
- A Cade
- Department of Paediatrics and Child Health, Clarendon Wing, Leeds General Infirmary, Belmont Grove, Leeds LS2 9NS, UK
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Mason SA. Service reconfiguration: preparing for clinical integration. Healthc Exec 1998; 13:12-6. [PMID: 10181095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Affiliation(s)
- S A Mason
- APACHE Medical Systems, McLean, VA, USA
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Mason SA, Hopkins M, McGowan RA, Brown M. Virtual roundtable: the do's and don'ts of negotiating a merger. Health Syst Lead 1996; 3:14-7. [PMID: 10159067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Forsyth VT, Langan P, Whalley MA, Mahendrasingam A, Wilson CC, Giesen U, Dauvergne MT, Mason SA, Fuller W. Time-of-flight Laue fiber diffraction studies of perdeuterated DNA. Basic Life Sci 1996; 64:359-67. [PMID: 9031520 DOI: 10.1007/978-1-4615-5847-7_31] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The diffractometer SXD at the Rutherford Appleton Laboratory ISIS pulsed neutron source has been used to record high resolution time-of-flight Laue fiber diffraction data from DNA. These experiments, which are the first of their kind, were undertaken using fibers of DNA in the A conformation and prepared using deuterated DNA in order to minimise incoherent background scattering. These studies complement previous experiments on instrument D19 at the Institut Laue Langevin using monochromatic neutrons. Sample preparation involved drawing large numbers of these deuterated DNA fibers and mounting them in a parallel array. The strategy of data collection is discussed in terms of camera design, sample environment and data collection. The methods used to correct the recorded time-of-flight data and map it into the final reciprocal space fiber diffraction dataset are also discussed. Difference Fourier maps showing the distribution of water around A-DNA calculated on the basis of these data are compared with results obtained using data recorded from hydrogenated A-DNA on D19. Since the methods used for sample preparation, data collection and data processing are fundamentally different for the monochromatic and Laue techniques, the results of these experiments also afford a valuable opportunity to independently test the data reduction and analysis techniques used in the two methods.
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Affiliation(s)
- V T Forsyth
- Department of Physics, Keele University, Staffordshire, United Kingdom
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Fuller W, Forsyth VT, Mahendrasingam A, Langan P, Pigram WJ, Mason SA, Wilson CC. DNA hydration studied by neutron fiber diffraction. Basic Life Sci 1996; 64:345-58. [PMID: 9031519 DOI: 10.1007/978-1-4615-5847-7_30] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The development of neutron high angle fiber diffraction to investigate the location of water around the deoxyribonucleic acid (DNA) double-helix is described. The power of the technique is illustrated by its application to the D and A conformations of DNA using the single crystal diffractometer, D19, at the Institut Laue-Langevin. Grenoble and the time of flight diffractometer, SXD, at the Rutherford Appleton ISIS Spallation Neutron Source. These studies show the existence of bound water closely associated with the DNA. The patterns of hydration in these two DNA conformations are quite distinct and are compared to those observed in X-ray single crystal studies of two-stranded oligodeoxynucleotides. Information on the location of water around the DNA double-helix from the neutron fiber diffraction studies is combined with that on the location of alkali metal cations from complementary X-ray high angle fiber diffraction studies at the Daresbury Laboratory SRS using synchrotron radiation. These analyses emphasize the importance of viewing DNA, water and ions as a single system with specific interactions between the three components and provide a basis for understanding the effect of changes in the concentration of water and ions in inducing conformational transitions in the DNA double-helix.
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Affiliation(s)
- W Fuller
- Department of Physics, Keele University, Staffordshire, United Kingdom
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Mason SA. Consultants must keep act clean. Mod Healthc 1995; 25:28. [PMID: 10151399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Mason SA, Seymour DW, Roach WH. The joint operating company: operational and legal considerations. Health Care Strateg Manage 1995; 13:6-8. [PMID: 10144167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Affiliation(s)
- S A Mason
- National Health Advisors, McLean, VA, USA
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Mason SA, Seymour DW. The joint operating company: an innovative approach to collaboration. Health Care Strateg Manage 1995; 13:11-3. [PMID: 10143018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
Abstract
Hospitals interested in horizontal integration often run into difficulties. In spite of otherwise sound business logic for two organizations to merge, there may be political, legal or financial reasons why a merger option cannot be pursued. Increasingly, enterprises are turning to a joint operating company structure as the solution to their needs. Scott A. Mason and Donald W. Seymour, partners with consulting firm National Health Advisors, explore situations where a JOC model of collaboration may be appropriate.
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Affiliation(s)
- S A Mason
- National Health Advisors, McLean, VA, USA
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Mason SA. Competition is not a four-letter word. Hosp Health Netw 1994; 68:60. [PMID: 8269013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- S A Mason
- National Health Advisors, McLean, VA
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Mason SA, Schumacher EJ, Seymour DW. Assessing models for integration: a strategic analysis. Health Syst Lead 1994; Suppl:8-18. [PMID: 10140093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Mason SA. Young, scarred children and their mothers--a short-term investigation into the practical, psychological and social implications of thermal injury to the preschool child. Part I: Implications for the mother. Burns 1993; 19:495-500. [PMID: 8292233 DOI: 10.1016/0305-4179(93)90006-t] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A short-term, prospective study, using both quantitative and qualitative methods, was designed to determine the practical, psychological and social implications of thermal injury resulting in scarring, for the mothers of thermally injured children, during the 6 months following the child's discharge from hospital. Mothers of 57 thermally injured children under 5 years of age were interviewed whilst the child was in hospital and at home, at 1 week, 2 months and 6 months following hospital discharge. Thermal injuries ranged from 1 to 41 per cent of body surface area and all required skin grafting. Qualitative analysis of interview transcripts resulted in the development of a model of the mother's response--The Maternal Thermal Injury Response Pattern (MTIRP)--which describes a phasic pattern of general response categories. The mothers' psychiatric morbidity was measured using Goldberg's (1978) 60-item General Health Questionnaire (GHQ). The mean of the mothers' total GHQ scores was 2.42 for the retrospective, pre-injury score, 24.5 at the hospital interview and 5.96 at 6 months following the child's discharge from hospital. In conclusion, the mother is a neglected victim of a young child's thermal injury. Use of the MTIRP as an educational tool for carers would promote increased understanding and, thus, more appropriate support.
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Affiliation(s)
- S A Mason
- Booth Hall Children's Hospital, Manchester, UK
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Mason SA, Housley PR. Site-directed mutagenesis of the phosphorylation sites in the mouse glucocorticoid receptor. J Biol Chem 1993; 268:21501-4. [PMID: 8407999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The functional significance of receptor phosphorylation in mediating the actions of glucocorticoids remains undefined. The identification of seven phosphorylation sites in the mouse glucocorticoid receptor (Bodwell, J. E., Orti, E., Coull, J. M., Pappin, D. J. C., Smith, L. I., and Swift, F. (1991) J. Biol. Chem. 266, 7549-7555) permits a direct examination of the potential regulatory role of glucocorticoid receptor phosphorylation in transactivation. Using oligonucleotide-directed mutagenesis of the mouse glucocorticoid receptor cDNA, we have substituted alanine or aspartate for the residues phosphorylated in this ligand-dependent transcription factor. COS-1 cells were cotransfected with mutant receptor cDNA expression vectors and a reporter plasmid containing the glucocorticoid-inducible mouse mammary tumor virus promoter linked to chloramphenicol acetyltransferase in order to characterize the effect of these substitutions on receptor-mediated gene expression. Substitution of alanine or aspartate at single phosphorylation sites does not prevent receptor transactivation. Receptors containing multiple substitutions of alanine or aspartate at the major phosphorylation sites in the acidic domain elicit levels of hormone-induced reporter gene expression that are comparable to wild-type receptors. Mutant receptors substituted with alanine at the five phosphorylation sites conserved among the rat, human, and mouse receptors exhibit a 22% decrease in transcriptional activity. Receptors mutated at all seven sites display a similar modest reduction. These results demonstrate that receptor phosphorylation at these seven identified residues is not a major determinant in glucocorticoid receptor transcriptional activity at the mouse mammary tumor virus promoter.
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Affiliation(s)
- S A Mason
- Department of Pharmacology, School of Medicine, University of South Carolina, Columbia 29208
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Abstract
There is an apparent lack of epistemological rigour when quantitative and qualitative methods are combined in the same study, because they reflect opposing positivist and interpretive perspectives. When and how to use methodological pluralism is discussed in this article.
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Langan P, Forsyth VT, Mahendrasingam A, Pigram WJ, Mason SA, Fuller W. A high angle neutron fibre diffraction study of the hydration of the A conformation of the DNA double helix. J Biomol Struct Dyn 1992; 10:489-503. [PMID: 1492921 DOI: 10.1080/07391102.1992.10508664] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A high angle neutron fibre diffraction study of the distribution of water around the A-form of DNA has been performed using the diffractometer D19 at the Institut Laue-Langevin, Grenoble. These experiments have exploited the ability to replace H2O surrounding the DNA by D2O so that isotopic difference Fourier maps can be computed in which peaks are identified with the distribution of water in the unit cell. All peaks of significant height have been accounted for by four families of water molecules whose positions and occupancies have been determined using least squares refinement. The coordinates of the water peaks making up each family do not deviate significantly from a regular helical arrangement with the same parameters as the DNA. Two of these families are of particular interest. The first consists of water molecules in the major groove linking successive charged phosphate oxygens along the polynucleotide chains. The second is associated with bases in the major groove and forms a central core of density along the helix axis. These two families provide a layer of hydration lining the interior wall of the major groove leaving a central channel to accommodate cations. The relationship between these observations and conformational stability is discussed.
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Affiliation(s)
- P Langan
- Department of Physics, Keele University, Staffordshire
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Fletcher CA, Mason SA. Aerosol bronchodilator administration distally in a tracheal tube. Anaesthesia 1992; 47:84-5. [PMID: 1536434 DOI: 10.1111/j.1365-2044.1992.tb01994.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Mason SA. Network integration. A new vision for Catholic healthcare systems in the 1990s. Health Prog 1990; 71:32-4, 46-7. [PMID: 10108005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
The 1990s will be the decade of network integration for many of the nation's healthcare organizations. Catholic healthcare systems will have to refocus on local and regional healthcare delivery. To succeed in local and regional markets, the systems will have to offer various levels of care through numerous types of providers, share services among facilities, cooperate with secular organizations, and build stronger affiliations with local parishes. Managing this change (from offering fragmented healthcare services to offering integrated services) will be a major challenge facing organizations in the decade ahead. They must develop a clearly articulated vision to provide stability during this time of rapid change. To meet the challenges of the 1990s, Catholic healthcare systems will have to determine the types of functional sharing that will be beneficial at the local level, divest and transfer sponsorship of facilities that burden the system's mission, and expand the activities of the laity.
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Abstract
Three individuals who exhibited self-injurious behavior (SIB) were exposed to sensory-integrative therapy. Prior to treatment, a functional analysis baseline was conducted to identify the motivational features of their SIB. One subject's SIB appeared to be an attention-getting response (maintained by positive reinforcement), which varied subsequently as a function of attention being either withheld or provided noncontingently during sensory-integration sessions. The 2nd subject displayed a pattern of responding suggestive of stereotypic SIB (maintained by automatic reinforcement), which paradoxically increased during sensory-integration sessions. The 3rd subject's SIB appeared to function as an escape response (maintained by negative reinforcement), and his behavior during sensory-integration sessions was similar to that observed during baseline sessions in which demands were not present. The SIB of all 3 subjects later was reduced when behavior interventions were applied. The data presented raise questions about the active components of sensory-integrative therapy and the functional types of SIB for which it might be appropriate.
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Affiliation(s)
- S A Mason
- Department of Special Education, University of Maryland, College Park 20742
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Abstract
Interactions with water are crucial to the conformation assumed by the DNA double helix. The location of water around the D conformation has been investigated in a neutron fibre diffraction study which shows that water is ordered in the minor groove of the DNA. The D conformation is important since its occurrence is limited to specific DNA base pair sequences which have been identified as functionally significant. This study is of particular interest because the D conformation has not been reported in single crystal studies of oligonucleotides.
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Affiliation(s)
- V T Forsyth
- Department of Physics, University of Keele, Staffordshire, UK
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Abstract
There is a need for practical methods of reinforcer assessment that systematically track ongoing changes in clients' preferences. In this study, the effects of a time-efficient reinforcer assessment package were evaluated in a multiple baseline across 3 preschoolers with autism, comparing individualized item selections by experienced teachers with children's presession preferences for items of various sensory qualities. Systematic assessment of children's reinforcers for correct responding virtually eliminated nontargeted maladaptive behaviors, as well as yielding expected improvements in accuracy. The powerful side-effects of potent reinforcers underline the importance of increased attention to reinforcer assessment in research and practice.
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Affiliation(s)
- S A Mason
- Department of Psychology, University of Massachusetts, Amherst 01003
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Mason SA. Can a merger support the mission? Trustee 1988; 41:15. [PMID: 10302360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Wass JA, Mason SA. 150th anniversary of the RMBF (Royal Medical Benevolent Fund). Lancet 1986; 2:1327. [PMID: 2878187 DOI: 10.1016/s0140-6736(86)91447-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Abstract
Single-crystal neutron diffraction has been used to observe the interactions between deuterated ethanol (CD3CD2OH) and lysozyme in triclinic crystals of hen egg white lysozyme soaked in 25% (v/v) ethanol solutions. A total of 6047 observed reflections to a resolution of 2 A were used, and 13 possible ethanol sites were identified. The three highest occupied sites are close to locations for bromoethanol found in an earlier study by Yonath et al. [Yonath, A., Podjarny, A., Honig, B., Traub, W., Sielecki, A., Herzberg, O., & Moult, J. (1978) Biophys. Struct. Mech. 4, 27-36]. Structure refinements including a model for the flat solvent lead to a final crystallographic agreement factor of 0.097. Comparison with earlier neutron studies on triclinic lysozyme showed that neither the molecular structure nor the thermal motions were affected significantly by the ethanol. A detailed analysis of the ethanol-lysozyme contacts showed 61% of these to be with hydrophobic sites, in agreement with the dominant hydrophobic nature of ethanol. This, together with the fact that the molecular structure of lysozyme is not perturbed, suggests a model for denaturation of lysozyme by alcohol, which proceeds via a dehydration of the protein at high alcohol concentration.
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Mason SA. Management implications of a shifting marketplace. Hosp Health Serv Adm 1984; 29:71-83. [PMID: 10310387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Bentley GA, Delepierre M, Dobson CM, Wedin RE, Mason SA, Poulsen FM. Exchange of individual hydrogens for a protein in a crystal and in solution. J Mol Biol 1983; 170:243-7. [PMID: 6631963 DOI: 10.1016/s0022-2836(83)80235-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
A preliminary comparison of the solvent exchange of individual hydrogens of a protein in solution and in a crystal has been possible by using data for lysozyme from 1H nuclear magnetic resonance and neutron diffraction studies. It is suggested that this approach enables a direct comparison of local dynamical behaviour in the two states. The results indicate markedly similar behaviour for many residues, but significant differences are indicated in several regions of the protein.
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Mason SA. The multihospital development process and strategic planning. Hosp Health Serv Adm 1980; 26:52-65. [PMID: 10298435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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