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Filip N, Pustam A, Ells V, Grosicki KMT, Yang J, Oguejiofor I, Bishop CD, DeMont ME, Smith-Palmer T, Wyeth RC. Fouling-release and chemical activity effects of a siloxane-based material on tunicates. MARINE ENVIRONMENTAL RESEARCH 2016; 116:41-50. [PMID: 26986763 DOI: 10.1016/j.marenvres.2016.02.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Revised: 02/26/2016] [Accepted: 02/28/2016] [Indexed: 06/05/2023]
Abstract
The antifouling performance of a siloxane-based elastomeric impression material (EIM) was compared to that of two silicone fouling-release coatings, Intersleek 757 and RTV-11. In field immersion trials, the EIM caused the greatest reduction in fouling by the solitary tunicate Ciona intestinalis and caused the longest delay in the progression of fouling by two species of colonial tunicate. However, in pseudobarnacle adhesion tests, the EIM had higher attachment strengths. Further laboratory analyses showed that the EIM leached alkylphenol ethoxylates (APEs) that were toxic to C. intestinalis larvae. The EIM thus showed the longest duration of chemical activity measured to date for a siloxane-based coating (4 months), supporting investigations of fouling-release coatings that release targeted biocides. However, due to potential widespread effects of APEs, the current EIM formulation should not be considered as an environmentally-safe antifoulant. Thus, the data also emphasize consideration of both immediate and long-term effects of potentially toxic constituents released from fouling-release coatings.
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Affiliation(s)
- Natalia Filip
- Department of Biology, St Francis Xavier University, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada; Centre for Biofouling Research, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada.
| | - Amanda Pustam
- Department of Chemistry, St Francis Xavier University, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada; Centre for Biofouling Research, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada.
| | - Veronica Ells
- Department of Biology, St Francis Xavier University, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada; Centre for Biofouling Research, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada.
| | - Kathleen M T Grosicki
- Department of Biology, St Francis Xavier University, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada; Centre for Biofouling Research, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada.
| | - Jin Yang
- Department of Chemistry, St Francis Xavier University, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada; Centre for Biofouling Research, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada.
| | - Ikenna Oguejiofor
- Department of Chemistry, St Francis Xavier University, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada; Centre for Biofouling Research, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada.
| | - Cory D Bishop
- Department of Biology, St Francis Xavier University, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada; Centre for Biofouling Research, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada.
| | - M Edwin DeMont
- Department of Biology, St Francis Xavier University, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada; Centre for Biofouling Research, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada.
| | - Truis Smith-Palmer
- Department of Chemistry, St Francis Xavier University, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada; Centre for Biofouling Research, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada.
| | - Russell C Wyeth
- Department of Biology, St Francis Xavier University, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada; Centre for Biofouling Research, 2321 Notre Dame Ave, Antigonish, Nova Scotia, B2G 2W5, Canada.
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Edge JA, Jakes RW, Roy Y, Hawkins M, Winter D, Ford-Adams ME, Murphy NP, Bergomi A, Widmer B, Dunger DB. The UK case-control study of cerebral oedema complicating diabetic ketoacidosis in children. Diabetologia 2006; 49:2002-9. [PMID: 16847700 DOI: 10.1007/s00125-006-0363-8] [Citation(s) in RCA: 131] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2006] [Accepted: 05/25/2006] [Indexed: 02/08/2023]
Abstract
AIMS/HYPOTHESIS Cerebral oedema complicating diabetic ketoacidosis (DKA) remains the major cause of morbidity and mortality in children with type 1 diabetes, but its aetiology remains unknown. Our objective was to determine the impact of baseline biochemical factors and of treatment-related variables on risk of the development of cerebral oedema in children with DKA. MATERIALS AND METHODS This was a national UK case-control study. Through the British Paediatric Surveillance Unit we identified 43 cases of cerebral oedema. Through a parallel reporting system, we also identified 2,940 episodes of DKA and selected 169 control subjects on the basis of comparable age, sex, numbers of new or known cases of diabetes and date of admission. Baseline biochemical data and treatment-related variables were extracted from the clinical notes of cases and control subjects. RESULTS Allowing for differences in age, sex and new or known diabetes, cases were more acidotic at diagnosis of DKA (odds ratio [OR] for events in the least acidotic compared with the most acidotic tertile=0.02 [95% CI: 0.002-0.15], p<0.001). In addition, cases had higher potassium and urea levels at baseline. Calculated osmolality and baseline glucose were not significantly different. After allowing for severity of acidosis, insulin administration in the first hour (OR 12.7 [1.41-114.5], p=0.02) and volume of fluid administered over the first 4 h (OR 6.55 [1.38-30.97], p=0.01) were associated with risk. Low baseline plasma sodium and an elevated p(a)CO(2) also contributed to risk in the final regression model. Bicarbonate administration was not associated with increased risk of an event when corrected for acidosis. CONCLUSIONS/INTERPRETATION In this case-control study of DKA, baseline acidosis and abnormalities of sodium, potassium and urea concentrations were important predictors of risk of cerebral oedema. Additional risk factors identified were early administration of insulin and high volumes of fluid. These observations should be taken into account when designing treatment protocols.
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Affiliation(s)
- J A Edge
- Department of Paediatrics, John Radcliffe Hospital, Oxford, UK
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de Vocht F, van Drooge H, Engels H, Kromhout H. Exposure, health complaints and cognitive performance among employees of an MRI scanners manufacturing department. J Magn Reson Imaging 2006; 23:197-204. [PMID: 16374876 DOI: 10.1002/jmri.20485] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To assess sensory effects and other health complaints that are reported by system testers working near magnetic resonance imaging (MRI) magnets, realizing that it is believed that exposure up to 8 T is safe for humans. MATERIALS AND METHODS Levels of exposure to static magnetic fields (SMFs), movement speed during exposure, health complaints, and cognitive performance among employees in an MRI-manufacturing department and at a reference department have been analyzed. Mercury concentrations in urine samples were determined to analyze whether they depend on exposure to SMFs. RESULTS Average exposure of system testers was 25.9 mT/8 hours at a 1.0-T system and 40.4 mT/8 hours at a 1.5-T system. Vertigo, metallic taste, and concentration problems were more reported among workers of MRI-fabrication than in the reference department. Cognitive performance was tested outside the SMF, and no significant changes were detected. CONCLUSION This study suggests that any effects on cognitive functions are acute and transient and disappear rapidly after exposure has ended. All complaints, except for headaches, were more frequently reported by "fast movers" than by "slow movers," and depended on field strength and duration of exposure. Mercury-levels in urine were not affected.
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Affiliation(s)
- Frank de Vocht
- Environmental and Occupational Health Division, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
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de Vocht F, van-Wendel-de-Joode B, Engels H, Kromhout H. Neurobehavioral effects among subjects exposed to high static and gradient magnetic fields from a 1.5 Tesla magnetic resonance imaging system?A case-crossover pilot study. Magn Reson Med 2003; 50:670-4. [PMID: 14523950 DOI: 10.1002/mrm.10604] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The interactive use of magnetic resonance imaging (MRI) techniques is increasing in operating theaters. A study was performed on 17 male company volunteers to assess the neurobehavioral effects of exposure to magnetic fields from a 1.5 Tesla MRI system. The subjects' neurobehavioral performances on a neurobehavioral test battery were compared in four 1-hr sessions with and without exposure to magnetic fields, and with and without additional movements. Adverse effects were found for hand coordination (-4%, P < 0.05; Pursuit Aiming II) and near visual contrast sensitivity (-16% and -15%, P < 0.10; Vistech 6000). The results from the remaining tests were inconclusive due to a strong learning effect. No additional effect from gradient fields was detected. The results indicate that working near a 1.5 Tesla MRI system may lead to neurobehavioral effects. Further research is recommended, especially in members of operating teams using interactive MRI systems.
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Affiliation(s)
- Frank de Vocht
- Environmental and Occupational Health Division, Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
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Banse X, Devogelaer JP, Lafosse A, Sims TJ, Grynpas M, Bailey AJ. Cross-link profile of bone collagen correlates with structural organization of trabeculae. Bone 2002; 31:70-6. [PMID: 12110415 DOI: 10.1016/s8756-3282(02)00800-1] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Little is known regarding the mechanisms that govern the structural organization of cancellous bone. In this study, we compare the nature of the collagen in vertebral cancellous bone with the structural organization of its trabecular network. Cylindrical specimens of cancellous bone from vertebrae were obtained from nine autopsy subjects (ages 46-88). In each subject, eight pairs of corresponding samples were obtained from three levels in the spine and three areas within the vertebral body, leading to a total of 68 pairs of samples. The cylinders from one side were used for morphometry and the classical morphometrical parameters were obtained (BV/TV, bone volume fraction; Tb.Th, trabecular thickness; Tb.N, number; Tb.Sp, trabecular spacing) and strut analysis (TSL, total strut length; Nd, number of nodes; Fe, number of free-ends). The amount of osteoid bone was also quantified. The cylinders from the other side were powdered and used for collagen assessment, including the amount of collagen (% w/w), and its content in immature cross-links; such as hydroxylysinonorleucine (mol/mol of collagen) and dihydroxylysinornorleucine, as well as stable mature cross-links, such as hydroxylysylpyridinoline (HP), lysylpyridinoline (LP), and the pyrrole cross-links. A random regression model was used to explore the correlations. None of the biochemical parameters correlated with the BV/TV except the ratio between immature and mature cross-links (eta(2) = 0.34, p < 0.05). There was no relationship between the amount of osteoid bone and the cross-link profile. However, the concentration of pyrrole and HP cross-links in the bone samples correlated with the structural organization of its trabeculae, but in an opposite direction. Hence, the pyrrole/HP ratio was a good predictor of Tb.Th, Tb.N, Tb.Sp, and TSL (eta(2) > 0.65 and p < 0.01) as well as Fe and star marrow space (eta(2) > 0.45 and p < 0.05). The cylinders from subjects with high pyrrole or low HP in their bone collagen had a relatively thick and simple structure. Those with low pyrrole and high HP had relatively thin trabeculae that were more numerous and spread over a complex network. The relative concentrations of the pyrrole and pyridinoline cross-links appear to reflect the structural organization of the trabeculae.
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Affiliation(s)
- X Banse
- Orthopaedic Research Laboratory and Arthritis Unit, Université Catholique de Louvain, Brussels, Belgium.
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