200 results on '"Wilkinson JL"'
Search Results
2. The long QT syndrome and seizures in childhood
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DAVIS, AM, primary and WILKINSON, JL, additional
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- 1998
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3. An operation for large scrotal hydrocele
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Wilkinson Jl
- Subjects
Male ,medicine.medical_specialty ,business.industry ,medicine.disease ,Testicular Hydrocele ,Surgery ,Hydrocele ,Methods ,Scrotum ,medicine ,Humans ,Testicular torsion ,business ,Spermatic Cord Torsion - Abstract
A relatively minor operation of partial eversion in which some residual sac is left in situ has been performed in over 500 cases of large tropical hydrocele. The method is applicable to smaller hydroceles, and also provides a method of treating recurrent testicular torsion.
- Published
- 1973
4. Variations in the morphology of the ventricular septal defect and disposition of the atrioventricular conduction tissues in tetralogy of Fallot
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D F Dickinson, D I Hamilton, A Smith, Wilkinson Jl, and Robert H. Anderson
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Pulmonary and Respiratory Medicine ,Heart Septal Defects, Ventricular ,congenital, hereditary, and neonatal diseases and abnormalities ,medicine.medical_specialty ,business.industry ,Atrioventricular conduction ,Fibrous tissue ,medicine.disease ,Surgical anatomy ,Internal medicine ,cardiovascular system ,Cardiology ,Atrioventricular Node ,Tetralogy of Fallot ,Medicine ,Humans ,Surgery ,Atrioventricular bundle ,cardiovascular diseases ,Cardiology and Cardiovascular Medicine ,business - Abstract
Seventeen heart specimens with tetralogy of Fallot were studied to assess the anatomy of the ventricular septal defect and the disposition and potential vulnerability to surgical trauma of the atrioventricular conduction tissue. Eleven had defects of the perimembranous type. In the majority of these cases the non-branching and branching atrioventricular bundle lay posterior to the defect in a position unlikely to be damaged during closure of the defect. However, in one case, the non-branching bundle extended onto the rim of the defect and in a further 4 cases, other major components of the atrioventricular conduction tissue appeared vulnerable. Six ventricular septal defects were of the muscular outlet type and the atrioventricular conduction tissue did not appear vulnerable in any case of this type. Conclusive differentiation between perimembranous and muscular outlet defects was not always possible on gross morphological examination. It is suggested that the crest of the muscular septum and fibrous tissue in the posterior corner of the ventricular septal defect should be avoided during closure of the defect.
- Published
- 1982
5. The epidemiology of childhood cardiomyopathy in Australia.
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Nugent AW, Daubeney PEF, Chondros P, Carlin JB, Cheung M, Wilkinson LC, Davis AM, Kahler SG, Chow CW, Wilkinson JL, Weintraub RG, and National Australian Childhood Cardiomyopathy Study
- Published
- 2003
6. Pharmaceutical Pollution of the English National Parks.
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Boxall ABA, Collins R, Wilkinson JL, Swan C, Bouzas-Monroy A, Jones J, Winter E, Leach J, Juta U, Deacon A, Townsend I, Kerr P, Paget R, Rogers M, Greaves D, Turner D, and Pearson C
- Abstract
England's 10 national parks are renowned for their landscapes, wildlife, and recreational value. However, surface waters in the national parks may be vulnerable to pollution from human-use chemicals, such as active pharmaceutical ingredients (APIs), because of factors like ineffective wastewater treatment, seasonal tourism, a high proportion of elderly residents, and the presence of low-flow water bodies that limit dilution. The present study determined the extent of API contamination in the English national parks by monitoring 54 APIs in 37 rivers across all national parks over two seasons. Results were compared to existing data sets for UK cities and to concentration thresholds for ecological impacts and antimicrobial resistance selection. Results revealed widespread contamination of the national parks, with APIs detected at 52 out of 54 sites and in both seasons. Thirty-one APIs were detected, with metformin, caffeine, and paracetamol showing the highest mean concentrations and cetirizine, metformin, and fexofenadine being the most frequently detected. While total API concentrations were generally lower than seen previously in UK cities, locations in the Peak District and Exmoor had higher concentrations than most city rivers. Fourteen locations had concentrations of either amitriptyline, carbamazepine, clarithromycin, diltiazem, metformin, paracetamol, or propranolol above levels of concern for fish, invertebrates, and algae or for selection for antimicrobial resistance. Therefore, API pollution of the English national parks appears to pose risks to ecological health and potentially human health through recreational water use. Given that these parks are biodiversity hotspots with protected ecosystems, there is an urgent need for improved monitoring and management of pharmaceutical pollution and pollution more generally not only in national parks in England but also in similar environments across the world. Environ Toxicol Chem 2024;00:1-14. © 2024 The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC., (© 2024 The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.)
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- 2024
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7. Pharmaceuticals and Personal Care Products in the Aquatic Environment: How Can Regions at Risk be Identified in the Future?
- Author
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Wilkinson JL, Thornhill I, Oldenkamp R, Gachanja A, and Busquets R
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- Humans, Environmental Monitoring methods, Ecotoxicology, Asia, Pharmaceutical Preparations, Cosmetics toxicity, Cosmetics analysis, Water Pollutants, Chemical toxicity, Water Pollutants, Chemical analysis
- Abstract
Pharmaceuticals and personal care products (PPCPs) are an indispensable component of a healthy society. However, they are well-established environmental contaminants, and many can elicit biological disruption in exposed organisms. It is now a decade since the landmark review covering the top 20 questions on PPCPs in the environment (Boxall et al., 2012). In the present study we discuss key research priorities for the next 10 years with a focus on how regions where PPCPs pose the greatest risk to environmental and human health, either now or in the future, can be identified. Specifically, we discuss why this problem is of importance and review our current understanding of PPCPs in the aquatic environment. Foci include PPCP occurrence and what drives their environmental emission as well as our ability to both quantify and model their distribution. We highlight critical areas for future research including the involvement of citizen science for environmental monitoring and using modeling techniques to bridge the gap between research capacity and needs. Because prioritization of regions in need of environmental monitoring is needed to assess future/current risks, we also propose four criteria with which this may be achieved. By applying these criteria to available monitoring data, we narrow the focus on where monitoring efforts for PPCPs are most urgent. Specifically, we highlight 19 cities across Africa, Central America, the Caribbean, and Asia as priorities for future environmental monitoring and risk characterization and define four priority research questions for the next 10 years. Environ Toxicol Chem 2024;43:575-588. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC., (© 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.)
- Published
- 2024
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8. Advocacy at the Eighth World Congress of Pediatric Cardiology and Cardiac Surgery.
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Zheleva B, Verstappen A, Overman DM, Ahmad F, Ali SKM, Al Halees ZY, Atallah JG, Badhwar IE, Baker-Smith C, Balestrini M, Basken A, Bassuk JS, Benson L, Capelli H, Carollo S, Chowdhury D, Çiçek MS, Cohen MI, Cooper DS, Deanfield JE, Dearani J, Del Valle B, Dodds KM, Du J, Edwin F, Ekure E, Fatema NN, Gomanju A, Hasan B, Henry L, Hugo-Hamman C, Iyer KS, Jatene MB, Jenkins KJ, Karamlou T, Karl TR, Kirklin JK, Kreutzer C, Kumar RK, Lopez KN, Macedo AP, Marino BS, Marwali EM, Meijboom FJ, Mattos SS, Najm H, Newlin D, Novick WM, Qureshi SSA, Rahmat B, Raylman R, Saltik IL, Sable C, Sandoval N, Saxena A, Scanlan E, Sholler GF, Smith J, St Louis JD, Tchervenkov CI, Tiong KG, Vida V, Vosloo S, Weinstein DJD, Wilkinson JL, Zuhlke L, and Jacobs JP
- Subjects
- Adult, Child, Humans, Cardiac Surgical Procedures, Cardiology, Heart Diseases
- Abstract
The Eighth World Congress of Pediatric Cardiology and Cardiac Surgery (WCPCCS) will be held in Washington DC, USA, from Saturday, 26 August, 2023 to Friday, 1 September, 2023, inclusive. The Eighth World Congress of Pediatric Cardiology and Cardiac Surgery will be the largest and most comprehensive scientific meeting dedicated to paediatric and congenital cardiac care ever held. At the time of the writing of this manuscript, The Eighth World Congress of Pediatric Cardiology and Cardiac Surgery has 5,037 registered attendees (and rising) from 117 countries, a truly diverse and international faculty of over 925 individuals from 89 countries, over 2,000 individual abstracts and poster presenters from 101 countries, and a Best Abstract Competition featuring 153 oral abstracts from 34 countries. For information about the Eighth World Congress of Pediatric Cardiology and Cardiac Surgery, please visit the following website: [www.WCPCCS2023.org]. The purpose of this manuscript is to review the activities related to global health and advocacy that will occur at the Eighth World Congress of Pediatric Cardiology and Cardiac Surgery .Acknowledging the need for urgent change, we wanted to take the opportunity to bring a common voice to the global community and issue the Washington DC WCPCCS Call to Action on Addressing the Global Burden of Pediatric and Congenital Heart Diseases . A copy of this Washington DC WCPCCS Call to Action is provided in the Appendix of this manuscript. This Washington DC WCPCCS Call to Action is an initiative aimed at increasing awareness of the global burden, promoting the development of sustainable care systems, and improving access to high quality and equitable healthcare for children with heart disease as well as adults with congenital heart disease worldwide.
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- 2023
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9. Assessment of the Potential Ecotoxicological Effects of Pharmaceuticals in the World's Rivers.
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Bouzas-Monroy A, Wilkinson JL, Melling M, and Boxall ABA
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- Environmental Monitoring, Pharmaceutical Preparations, Risk Assessment, Rivers chemistry, Ecotoxicology, Water Pollutants, Chemical analysis, Water Pollutants, Chemical toxicity
- Abstract
During their production, use, and disposal, active pharmaceutical ingredients (APIs) are released into aquatic systems. Because they are biologically active molecules, APIs have the potential to adversely affect nontarget organisms. We used the results of a global monitoring study of 61 APIs alongside available ecotoxicological and pharmacological data to assess the potential ecotoxicological effects of APIs in rivers across the world. Approximately 43.5% (461 sites) of the 1052 sampling locations monitored across 104 countries in a recent global study had concentrations of APIs of concern based on apical, nonapical, and mode of action-related endpoints. Approximately 34.1% of the 137 sampling campaigns had at least one location where concentrations were of ecotoxicological concern. Twenty-three APIs occurred at concentrations exceeding "safe" concentrations, including substances from the antidepressant, antimicrobial, antihistamine, β-blocker, anticonvulsant, antihyperglycemic, antimalarial, antifungal, calcium channel blocker, benzodiazepine, painkiller, progestin, and lifestyle compound classes. At the most polluted sites, effects are predicted on different trophic levels and on different endpoint types. Overall, the results show that API pollution is a global problem that is likely negatively affecting the health of the world's rivers. To meet the United Nations' Sustainable Development Goals, work is urgently needed to tackle the problem and bring concentrations down to an acceptable level. Environ Toxicol Chem 2022;41:2008-2020. © 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC., (© 2022 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.)
- Published
- 2022
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10. Pharmaceutical pollution of the world's rivers.
- Author
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Wilkinson JL, Boxall ABA, Kolpin DW, Leung KMY, Lai RWS, Galbán-Malagón C, Adell AD, Mondon J, Metian M, Marchant RA, Bouzas-Monroy A, Cuni-Sanchez A, Coors A, Carriquiriborde P, Rojo M, Gordon C, Cara M, Moermond M, Luarte T, Petrosyan V, Perikhanyan Y, Mahon CS, McGurk CJ, Hofmann T, Kormoker T, Iniguez V, Guzman-Otazo J, Tavares JL, Gildasio De Figueiredo F, Razzolini MTP, Dougnon V, Gbaguidi G, Traoré O, Blais JM, Kimpe LE, Wong M, Wong D, Ntchantcho R, Pizarro J, Ying GG, Chen CE, Páez M, Martínez-Lara J, Otamonga JP, Poté J, Ifo SA, Wilson P, Echeverría-Sáenz S, Udikovic-Kolic N, Milakovic M, Fatta-Kassinos D, Ioannou-Ttofa L, Belušová V, Vymazal J, Cárdenas-Bustamante M, Kassa BA, Garric J, Chaumot A, Gibba P, Kunchulia I, Seidensticker S, Lyberatos G, Halldórsson HP, Melling M, Shashidhar T, Lamba M, Nastiti A, Supriatin A, Pourang N, Abedini A, Abdullah O, Gharbia SS, Pilla F, Chefetz B, Topaz T, Yao KM, Aubakirova B, Beisenova R, Olaka L, Mulu JK, Chatanga P, Ntuli V, Blama NT, Sherif S, Aris AZ, Looi LJ, Niang M, Traore ST, Oldenkamp R, Ogunbanwo O, Ashfaq M, Iqbal M, Abdeen Z, O'Dea A, Morales-Saldaña JM, Custodio M, de la Cruz H, Navarrete I, Carvalho F, Gogra AB, Koroma BM, Cerkvenik-Flajs V, Gombač M, Thwala M, Choi K, Kang H, Ladu JLC, Rico A, Amerasinghe P, Sobek A, Horlitz G, Zenker AK, King AC, Jiang JJ, Kariuki R, Tumbo M, Tezel U, Onay TT, Lejju JB, Vystavna Y, Vergeles Y, Heinzen H, Pérez-Parada A, Sims DB, Figy M, Good D, and Teta C
- Subjects
- Ecosystem, Environmental Exposure, Environmental Monitoring, Humans, Pharmaceutical Preparations, Wastewater analysis, Wastewater chemistry, Water analysis, Water chemistry, Water Pollutants, Chemical analysis, Rivers chemistry, Water Pollution, Chemical analysis, Water Pollution, Chemical prevention & control
- Abstract
Environmental exposure to active pharmaceutical ingredients (APIs) can have negative effects on the health of ecosystems and humans. While numerous studies have monitored APIs in rivers, these employ different analytical methods, measure different APIs, and have ignored many of the countries of the world. This makes it difficult to quantify the scale of the problem from a global perspective. Furthermore, comparison of the existing data, generated for different studies/regions/continents, is challenging due to the vast differences between the analytical methodologies employed. Here, we present a global-scale study of API pollution in 258 of the world's rivers, representing the environmental influence of 471.4 million people across 137 geographic regions. Samples were obtained from 1,052 locations in 104 countries (representing all continents and 36 countries not previously studied for API contamination) and analyzed for 61 APIs. Highest cumulative API concentrations were observed in sub-Saharan Africa, south Asia, and South America. The most contaminated sites were in low- to middle-income countries and were associated with areas with poor wastewater and waste management infrastructure and pharmaceutical manufacturing. The most frequently detected APIs were carbamazepine, metformin, and caffeine (a compound also arising from lifestyle use), which were detected at over half of the sites monitored. Concentrations of at least one API at 25.7% of the sampling sites were greater than concentrations considered safe for aquatic organisms, or which are of concern in terms of selection for antimicrobial resistance. Therefore, pharmaceutical pollution poses a global threat to environmental and human health, as well as to delivery of the United Nations Sustainable Development Goals., Competing Interests: The authors declare no competing interest., (Copyright © 2022 the Author(s). Published by PNAS.)
- Published
- 2022
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11. Use of a large dataset to develop new models for estimating the sorption of active pharmaceutical ingredients in soils and sediments.
- Author
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Li J, Wilkinson JL, and Boxall ABA
- Subjects
- Adsorption, Geologic Sediments, Soil, Pharmaceutical Preparations, Soil Pollutants analysis
- Abstract
Information on the sorption of active pharmaceutical ingredients (APIs) in soils and sediments is needed for assessing the environmental risks of these substances yet these data are unavailable for many APIs in use. Predictive models for estimating sorption could provide a solution. The performance of existing models is, however, often poor and most models do not account for the effects of soil/sediment properties which are known to significantly affect API sorption. Therefore, here, we use a high-quality dataset on the sorption behavior of 54 APIs in 13 soils and sediments to develop new models for estimating sorption coefficients for APIs in soils and sediments using three machine learning approaches (artificial neural network, random forest and support vector machine) and linear regression. A random forest-based model, with chemical and solid descriptors as the input, was the best performing model. Evaluation of this model using an independent sorption dataset from the literature showed that the model was able to predict sorption coefficients of 90% of the test set to within a factor of 10 of the experimental values. This new model could be invaluable in assessing the sorption behavior of molecules that have yet to be tested and in landscape-level risk assessments., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2021
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12. An Automated Methodology for Non-targeted Compositional Analysis of Small Molecules in High Complexity Environmental Matrices Using Coupled Ultra Performance Liquid Chromatography Orbitrap Mass Spectrometry.
- Author
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Pereira KL, Ward MW, Wilkinson JL, Sallach JB, Bryant DJ, Dixon WJ, Hamilton JF, and Lewis AC
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- Chromatography, High Pressure Liquid, Chromatography, Liquid, Mass Spectrometry, Reproducibility of Results, Pesticides analysis, Water Pollutants, Chemical analysis
- Abstract
The life-critical matrices of air and water are among the most complex chemical mixtures that are ever encountered. Ultrahigh-resolution mass spectrometers, such as the Orbitrap, provide unprecedented analytical capabilities to probe the molecular composition of such matrices, but the extraction of non-targeted chemical information is impractical to perform via manual data processing. Automated non-targeted tools rapidly extract the chemical information of all detected compounds within a sample dataset. However, these methods have not been exploited in the environmental sciences. Here, we provide an automated and (for the first time) rigorously tested methodology for the non-targeted compositional analysis of environmental matrices using coupled liquid chromatography-mass spectrometric data. First, the robustness and reproducibility was tested using authentic standards, evaluating performance as a function of concentration, ionization potential, and sample complexity. The method was then used for the compositional analysis of particulate matter and surface waters collected from worldwide locations. The method detected >9600 compounds in the individual environmental samples, arising from critical pollutant sources, including carcinogenic industrial chemicals, pesticides, and pharmaceuticals among others. This methodology offers considerable advances in the environmental sciences, providing a more complete assessment of sample compositions while significantly increasing throughput.
- Published
- 2021
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13. Assessing the role of the "estuarine filter" for emerging contaminants: pharmaceuticals, perfluoroalkyl compounds and plasticisers in sediment cores from two contrasting systems in the southern U.K.
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Celis-Hernandez O, Cundy AB, Croudace IW, Ward RD, Busquets R, and Wilkinson JL
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- Environmental Monitoring, Geologic Sediments, Fluorocarbons, Pharmaceutical Preparations, Water Pollutants, Chemical analysis
- Abstract
The environmental occurrence, fate and ecotoxicity of emerging contaminants (ECs) has been the subject of increasing research, policy and public concern over the past two decades. While a wide range of publications have examined the environmental persistence and sediment/soil interactions of ECs following their discharge into aquatic environments, the extent to which ECs are sequestered in estuarine sediments, and the impact of this on their environmental persistence and supply to the ocean, in comparison remains unclear. This Article examines the environmental concentrations of seven, relatively water-soluble and environmentally mobile, ECs (including pharmaceuticals, perfluoroalkyl compounds, and plasticisers) in dated intertidal saltmarsh cores from two contrasting estuarine sites in the southern U.K. (one heavily urbanised/industrial, the other non-urbanised). Mean sediment EC concentrations are similar in both estuarine systems (in the range 0.1 (acetaminophen) to 17 (4-hydroxyacetophenone) ng/g dry weight). Despite their variable reported Log K
ow values (from ca. 0.5 to > 7), the ECs are all apparently mobile in the marsh systems studied, and where subsurface concentration maxima are present these most likely relate to local flushing or diffusive processes and cannot be clearly linked to likely input trends or changes in sediment geochemistry (including sedimentary organic carbon content). The "estuarine filter" here, at least with respect to intertidal saltmarsh sediments, shows reduced potential to sequester the seven ECs examined and mediate their supply to coastal and shelf environments., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)- Published
- 2021
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14. Evaluation of Existing Models to Estimate Sorption Coefficients for Ionisable Pharmaceuticals in Soils and Sludge.
- Author
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Carter LJ, Wilkinson JL, and Boxall ABA
- Abstract
In order to assess the environmental risk of a pharmaceutical, information is needed on the sorption of the compound to solids. Here we use a high-quality database of measured sorption coefficients, all determined following internationally recognised protocols, to evaluate models that have been proposed for estimating sorption of pharmaceuticals from chemical structure, some of which are already being used for environmental risk assessment and prioritization purposes. Our analyses demonstrate that octanol-water partition coefficient ( K
ow ) alone is not an effective predictor of ionisable pharmaceutical sorption in soils. Polyparameter models based on pharmaceutical characteristics in combination with key soil properties, such as cation exchange capacity, increase model complexity but yield an improvement in the predictive capability of soil sorption models. Nevertheless, as the models included in this analysis were only able to predict a maximum of 71% and 67% of the sorption coefficients for the compounds to within one log unit of the corresponding measured value in soils and sludge, respectively, there is a need for new models to be developed to better predict the sorption of ionisable pharmaceuticals in soil and sludge systems. The variation in sorption coefficients, even for a single pharmaceutical across different solid types, makes this an inherently difficult task, and therefore requires a broad understanding of both chemical and sorbent properties driving the sorption process., Competing Interests: A.B.A.B has received research funding from and has provided consultancy to pharmaceutical companies. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.- Published
- 2020
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15. Dissolved Mn(III) in water treatment works: Prevalence and significance.
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Johnson KL, McCann CM, Wilkinson JL, Jones M, Tebo BM, West M, Elgy C, Clarke CE, Gowdy C, and Hudson-Edwards KA
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- England, Prevalence, Wastewater analysis, Manganese analysis, Water Pollutants, Chemical analysis, Water Purification methods
- Abstract
Dissolved Mn(III) has been identified at all stages throughout a Water Treatment Works (WTW) receiving inflow from a peaty upland catchment in NE England. Ninety percent of the influent total manganese into the WTW is particulate Mn, in the form of Mn oxide (>0.2 μm). Approximately 9% (mean value, n = 22, range of 0-100%) of the dissolved (<0.2 μm) influent Mn is present as dissolved Mn(III). Mn(III) concentrations are highest (mean of 49% of total dissolved Mn; n = 26, range of 17-89%) within the WTW where water comes into contact with the organic-rich sludges which are produced as waste products in the WTW. These Mn(III)-containing wastewaters are recirculated to the head of the works and constitute a large input of Mn(III) into the WTW. This is the first report of Mn(III) being identified in a WTW. The ability of Mn(III) to act as both an oxidant and a reductant is of interest to the water industry. Understanding the formation and removal of Mn(III) within may help reduce Mn oxide deposits in pipe networks. Further understanding how the ratio of Mn(III) to Mn(II) can be used to optimise dissolved Mn removal would save the water industry significant money in reducing discoloration 'events' at the customers' tap., (Copyright © 2018. Published by Elsevier Ltd.)
- Published
- 2018
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16. Deficiency of the Wnt receptor Ryk causes multiple cardiac and outflow tract defects.
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Kugathasan K, Halford MM, Farlie PG, Bates D, Smith DP, Zhang YF, Roy JP, Macheda ML, Zhang D, Wilkinson JL, Kirby ML, Newgreen DF, and Stacker SA
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- Animals, Aorta, Thoracic abnormalities, Female, Mice, Morphogenesis, Pregnancy, Heart Defects, Congenital etiology, Pharynx abnormalities, Receptor Protein-Tyrosine Kinases physiology, Wnt Proteins metabolism
- Abstract
Ryk is a member of the receptor tyrosine kinase (RTK) family of proteins that control and regulate cellular processes. It is distinguished by binding Wnt ligands and having no detectable intrinsic protein tyrosine kinase activity suggesting Ryk is a pseudokinase. Here, we show an essential role for Ryk in directing morphogenetic events required for normal cardiac development through the examination of Ryk-deficient mice. We employed vascular corrosion casting, vascular perfusion with contrast dye, and immunohistochemistry to characterize cardiovascular and pharyngeal defects in Ryk
-/- embryos. Ryk-/- mice exhibit a variety of malformations of the heart and outflow tract that resemble human congenital heart defects. This included stenosis and interruption of the aortic arch, ventriculoarterial malalignment, ventricular septal defects and abnormal pharyngeal arch artery remodelling. This study therefore defines a key intersection between a subset of growth factor receptors involved in planar cell polarity signalling, the Wnt family and mammalian cardiovascular development.- Published
- 2018
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17. Spatial (bio)accumulation of pharmaceuticals, illicit drugs, plasticisers, perfluorinated compounds and metabolites in river sediment, aquatic plants and benthic organisms.
- Author
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Wilkinson JL, Hooda PS, Swinden J, Barker J, and Barton S
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- Animals, Aquatic Organisms chemistry, Aquatic Organisms drug effects, Aquatic Organisms isolation & purification, Aquatic Organisms metabolism, England, Environmental Monitoring methods, Fresh Water analysis, Illicit Drugs isolation & purification, Illicit Drugs metabolism, Pharmaceutical Preparations isolation & purification, Pharmaceutical Preparations metabolism, Plants chemistry, Plants metabolism, Plasticizers isolation & purification, Plasticizers metabolism, Potamogetonaceae chemistry, Potamogetonaceae metabolism, Solid Phase Extraction, Water Pollutants, Chemical isolation & purification, Water Pollutants, Chemical metabolism, Geologic Sediments analysis, Illicit Drugs analysis, Pharmaceutical Preparations analysis, Plants drug effects, Plasticizers analysis, Potamogetonaceae drug effects, Rivers chemistry, Water Pollutants, Chemical analysis
- Abstract
Organic contaminants such as pharmaceuticals, personal care products (PPCPs) and other emerging contaminants (ECs) are known to persist in the aquatic environment and many are indicated as endocrine, epigenetic, or other toxicants. Typically, the study of PPCPs/ECs in the aquatic environment is limited to their occurrence dissolved in river water. In this study, accumulation and spatial distribution of thirteen PPCPs/ECs were assessed in aquatic sediment (n = 23), periphyton (biofilm, n = 8), plants Callitriche sp. (n = 8) and Potamogeton sp. (n = 7) as well as amphipod crustaceans (Gammarus pulex, n = 10) and aquatic snails (Bithynia tentaculata, n = 9). All samples (n = 65) were collected from the Hogsmill, Blackwater and Bourne Rivers in southern England. Targeted PPCPs/ECs included pharmaceuticals, plasticisers, perfluorinated compounds, illicit drugs and metabolites. Extraction from solid matrices occurred using ultrasonic-assisted extraction followed by an in-house validated method for solid-phase extraction and subsequent liquid-chromatography tandem mass-spectrometry. Field-derived bioconcentration-factors and biota-sediment accumulation-factors were determined for all studied biota. Residues of studied contaminants were found in all sediment and biota. Concentrations of contaminants were generally higher in biota than sediment. Evidence suggests that the studied aquatic plants may effectively degrade bisphenol-A into its main transformation product hydroxyacetophenone, potentially mediated by cytochrome p450 and internalisation of contaminants into the cellular vacuole. A positive association between both hydrophobicity and PFC chain length and contaminant accumulation was observed in this work. Only PFCs, plasticisers and HAP were classified as either 'bioaccumulative' or 'very bioaccumulative' using BCF criteria established by guidelines of four governments. Contaminants appeared to be differentially bioaccumulative in biota, indicating there may be a need for a species-specific BCF/BSAF classification system. These data form a detailed accounting of PPCP/EC fate and distribution in the aquatic environment highlighting accumulation at lower trophic levels, a potential source for higher organisms., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
- Published
- 2018
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18. Spatial distribution of organic contaminants in three rivers of Southern England bound to suspended particulate material and dissolved in water.
- Author
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Wilkinson JL, Hooda PS, Swinden J, Barker J, and Barton S
- Abstract
The spatial distribution of pharmaceuticals, personal care products (PPCPs) and other emerging contaminants (ECs) such as plasticisers, perflourinated compounds (PFCs) and illicit drug metabolites in water and bound to suspended particulate material (SPM) is not well-understood. Here, we quantify levels of thirteen selected contaminants in water (n=88) and their partition to suspended particulate material (SPM, n=16) in three previously-unstudied rivers of Greater London and Southern England during a key reproduction/spawning period. Analysis was conducted using an in-house validated method for Solid Phase Extraction followed by High-Performance Liquid Chromatography-Tandem Mass-Spectrometry. Analytes were extracted from SPM using an optimised method for ultrasonic-assisted solvent extraction. Detection frequencies of contaminants dissolved in water ranged from 3% (ethinylestradiol) to 100% (bisphenol-A). Overall mean concentrations in the aqueous-phase ranged from 14.7ng/L (benzoylecgonine) to 159ng/L (bisphenol-A). Sewage treatment works (STW) effluent was the predominant source of pharmaceuticals, while plasticisers/perfluorinated compounds may additionally enter rivers via other sources. In SPM, detection frequencies ranged from 44% (PFOA) to 94% (hydroxyacetophenone). Mean quantifiable levels of analytes bound to SPM ranged from 13.5ng/g dry SPM (0.33ng bound/L water) perfluorononanoic acid to 2830ng/g dry SPM (14.3ng bound/L water) perfluorooctanesulfonic acid. Long chain (>C7) amphipathic and acidic PFCs were found to more preferentially bind to SPM than short chain PFCs and other contaminants (Kd=34.1-75.5 vs <5 respectively). Per capita daily contributions of studied contaminants entering rivers ranged from 0.157μg/person/day of benzoylecgonine (cocaine metabolite) to 58.6μg/person/day of bisphenol-A. The large sample size of this work (n=104) enabled ANOVA followed by Tukey HSD post-hoc tests to establish significant trends in PPCP/EC spatial distribution from headwaters through downstream stretches of studied rivers. Novel findings include environmental Kd calculations, the occurrence of contaminants in river headwaters, increases in contaminant metabolite concentrations downstream of STW effluents revealing possible in-river degradation or de-conjugation, the influence of polarity and acidity in the partition of contaminants to particulate-material, among others., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2017
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19. Evaluation of Diet-Related Infographics on Pinterest for Use of Behavior Change Theories: A Content Analysis.
- Author
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Wilkinson JL, Strickling K, Payne HE, Jensen KC, and West JH
- Abstract
Background: There is increasing interest in Pinterest as a method of disseminating health information. However, it is unclear whether the health information promoted on Pinterest is evidence-based or incorporates behavior change theory., Objectives: The objective of the study was to determine the presence of health behavior theory (HBT) constructs in pins found on Pinterest and assess the relationship between various pin characteristics and the likelihood of inclusion of HBT., Methods: A content analysis was conducted on pins collected from Pinterest identified with the search terms "nutrition infographic" and "healthy eating infographic." The coding rubric included HBT constructs, pin characteristics, and visual communication tools. Each HBT construct was coded as present or not present (yes=1, no=0). A total theory score was calculated by summing the values for each of the 9 constructs (range 0-9). Adjusted regression analysis was used to identify factors associated with the inclusion of health behavior change theory in pins (P<.05)., Results: The mean total theory score was 2.03 (SD 1.2). Perceived benefits were present most often (170/236, 72%), followed by behavioral capability (123/238, 51.7%) and perceived severity (79/236, 33.5%). The construct that appeared the least was self-regulation/self-control (2/237, 0.8%). Pin characteristics associated with the inclusion of HBT included a large amount of text (P=.01), photographs of real people (P=.001), cartoon pictures of food (P=.01), and the presence of references (P=.001). The number of repins (P=.04), likes (P=.01), and comments (P=.01) were positively associated with the inclusion of HBT., Conclusions: These findings suggest that current Pinterest infographics targeting healthy eating contain few HBT elements. Health professionals and organizations should create and disseminate infographics that contain more elements of HBT to better influence healthy eating behavior. This may be accomplished by creating pins that use both text and images of people and food in order to portray elements of HBT and convey nutritional information., Competing Interests: Conflicts of Interest: None declared., (©Jessica L Wilkinson, Kate Strickling, Hannah E Payne, Kayla C Jensen, Joshua H West. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 08.12.2016.)
- Published
- 2016
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20. Markers of anthropogenic contamination: A validated method for quantification of pharmaceuticals, illicit drug metabolites, perfluorinated compounds, and plasticisers in sewage treatment effluent and rain runoff.
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Wilkinson JL, Swinden J, Hooda PS, Barker J, and Barton S
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- Benzhydryl Compounds, Caprylates analysis, Fluorocarbons analysis, Illicit Drugs metabolism, Phenols, Plasticizers analysis, Rain chemistry, Rivers chemistry, Sewage chemistry, Solid Phase Extraction, Substance Abuse Detection methods, Sulfones, Tandem Mass Spectrometry, Environmental Monitoring methods, Pharmaceutical Preparations analysis, Wastewater chemistry, Water Pollutants, Chemical analysis
- Abstract
An effective, specific and accurate method is presented for the quantification of 13 markers of anthropogenic contaminants in water using solid phase extraction (SPE) followed by high performance liquid chromatography (HPLC) tandem mass spectrometry (MS/MS). Validation was conducted according to the International Conference on Harmonisation (ICH) guidelines. Method recoveries ranged from 77 to 114% and limits of quantification between 0.75 and 4.91 ng/L. A study was undertaken to quantify the concentrations and loadings of the selected contaminants in 6 sewage treatment works (STW) effluent discharges as well as concentrations in 5 rain-driven street runoffs and field drainages. Detection frequencies in STW effluent ranged from 25% (ethinylestradiol) to 100% (benzoylecgonine, bisphenol-A (BPA), bisphenol-S (BPS) and diclofenac). Average concentrations of detected compounds in STW effluents ranged from 3.62 ng/L (ethinylestradiol) to 210 ng/L (BPA). Levels of perfluorinated compounds (PFCs) perfluorooctanoic acid (PFOA) and perfluorononanoic acid (PFNA) as well as the plasticiser BPA were found in street runoff at maximum levels of 1160 ng/L, 647 ng/L and 2405 ng/L respectively (8.52, 3.09 and 2.7 times more concentrated than maximum levels in STW effluents respectively). Rain-driven street runoff may have an effect on levels of PFCs and plasticisers in receiving rivers and should be further investigated. Together, this method with the 13 selected contaminants enables the quantification of various markers of anthropogenic pollutants: inter alia pharmaceuticals, illicit drugs and their metabolites from humans and improper disposal of drugs, while the plasticisers and perfluorinated compounds may also indicate contamination from industrial and transport activity (street runoff)., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
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- 2016
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21. Future directions for interventions targeting PTSD in HIV-infected adults.
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Applebaum AJ, Bedoya CA, Hendriksen ES, Wilkinson JL, Safren SA, and O'Cleirigh C
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- Adult, Cognitive Behavioral Therapy, Humans, Stress Disorders, Post-Traumatic etiology, HIV Infections complications, Stress Disorders, Post-Traumatic therapy
- Abstract
Although studies consistently report high rates of comorbid posttraumatic stress disorder (PTSD) and HIV infection, development and testing of PTSD treatment interventions in HIV-infected adults is limited. As such, the purpose of this review was twofold. First, this review augments the three existing reviews of research for PTSD in HIV-infected adults conducted within the past 10 years. We found two empirically supported cognitive-behavioral therapy-based interventions for the treatment of trauma-related symptoms in HIV-infected adults. Due to the continued limited number of effective interventions for this population, a second aim of our review was to draw from the expansive field of effective PTSD interventions for the general population to propose ways that future clinical intervention research may be tailored for HIV-infected adults. Therefore, in addition to a review, we conceptualized this paper as an opportunity to generate an ideal preview of the field of intervention research in this population., (Copyright © 2015 Association of Nurses in AIDS Care. Published by Elsevier Inc. All rights reserved.)
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- 2015
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22. Paediatric heart transplantation in Australia comes of age: 21 years of experience in a national centre.
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Alexander PM, Swager A, Lee KJ, Shipp A, Konstantinov IE, Wilkinson JL, d'Udekem Y, Brizard C, and Weintraub RG
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- Adolescent, Australia epidemiology, Cardiomyopathies mortality, Child, Child, Preschool, Female, Heart Defects, Congenital mortality, Heart Failure mortality, Humans, Infant, Male, Retrospective Studies, Survival Analysis, Waiting Lists mortality, Cardiomyopathies surgery, Heart Defects, Congenital surgery, Heart Failure surgery, Heart Transplantation mortality, Tissue and Organ Procurement organization & administration
- Abstract
Background: Heart transplantation (HT) is established therapy for end-stage heart failure in children with cardiomyopathy or congenital heart disease., Aims: This review summarises experience at a national referral centre since the first local transplant., Methods: Medical records of children referred for HT between 1 April 1988 and 1 January 2010 were retrospectively reviewed. All patients listed for HT were included. Survival analysis was used to summarise wait-list time to death/transplant, and separately, time to death in HT patients., Results: One hundred and thirty-nine children were accepted on to the HT waiting list during the study (median age 7.7 (interquartile range (IQR) 2.5, 13.6) years), of whom 93 underwent HT (median age 10.9 (IQR 4.4, 14.6) years). Wait-list mortality was 32% (45 of 139 patients), lowest among children aged >10 years at listing (P < 0.001). Median time to HT was 69 days (range 29-146). Survival post-transplantation was 90% (95% confidence interval 82-95) at 1 year, 82% (72-89%) at 5 years and 68% (50-80%) at 10 years. Increasing case complexity over the study period included pre- and post-transplant circulatory support, management of pulmonary hypertension and introduction of ABO-incompatible HT for infants. Post-transplant survival did not vary according to age, pre-transplant diagnosis or use of pre-transplant circulatory support (all P > 0.05)., Conclusions: Results of paediatric HT in Australia are comparable with international results, despite limitations of geographic isolation, small population and low organ donation rate. Increasing case complexity has not impacted on post-transplant survival., (© 2014 The Authors; Internal Medicine Journal © 2014 Royal Australasian College of Physicians.)
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- 2014
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23. Anatomy of functionally single ventricle.
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Wilkinson JL and Anderson RH
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Hearts that have previously been called univentricular hearts, or single ventricles, can be described as having a univentricular atrioventricular connection. Most such hearts have two ventricular chambers, albeit one is small and incomplete-lacking an inlet component. The atriums of these hearts connect only to one of these ventricular chambers, which is usually the larger and dominant ventricle. Other hearts, with biventricular atrioventricular connections, may have hypoplasia of one ventricle, making it impossible to restore a biventricular circulation and such hearts are functionally univentricular. The term "functionally single ventricle" (or functionally univentricular heart) encompasses both these categories of malformation.
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- 2012
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24. The longitudinal relationships between rural adolescents' prosocial behaviors and young adult substance use.
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Carlo G, Crockett LJ, Wilkinson JL, and Beal SJ
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- Adolescent, Alcoholic Intoxication epidemiology, Female, Health Behavior, Humans, Life Style, Male, Risk-Taking, Young Adult, Adolescent Behavior, Rural Population statistics & numerical data, Substance-Related Disorders epidemiology
- Abstract
While many adolescents and young adults experiment with substances (e.g., alcohol, cigarette smoking, marijuana), recent research suggests that rural youth and young adults may be more at risk for substance use than their urban counterparts. This study was designed to examine the longitudinal relationships between rural adolescents' prosocial behaviors and substance use in young adulthood. Furthermore, we examined the potential mediating effects of adolescent substance use, academic investment, and delinquency. Rural youth (N = 531; 263 girls) were surveyed in grades 10-12 (Time 1; M age = 16.17; SD = .91) and again in early adulthood (Time 2). Measures of prosocial behaviors, substance use, academic investment, and deviant activities were assessed at Time 1. At Time 2, measures of marijuana use, cigarette smoking, and getting drunk were administered. Overall, the findings showed that rural adolescents who frequently exhibit prosocial behaviors are less likely to engage in substance use in young adulthood than those who exhibit relatively low levels of prosocial behaviors. These findings indicate that prosocial behaviors may have positive health consequences, establishing behavioral trajectories that lead to lower levels of risky health behaviors in adulthood in rural populations.
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- 2011
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25. A review of treating depression in diabetes: emerging findings.
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Markowitz SM, Gonzalez JS, Wilkinson JL, and Safren SA
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- Adolescent, Adult, Antidepressive Agents therapeutic use, Child, Cognitive Behavioral Therapy, Cooperative Behavior, Depressive Disorder psychology, Health Education, Humans, Mental Health Services, Patient Education as Topic, Psychotherapy, Self Care, Treatment Outcome, Depressive Disorder complications, Depressive Disorder therapy, Diabetes Mellitus, Type 1 complications, Diabetes Mellitus, Type 1 psychology, Diabetes Mellitus, Type 2 complications, Diabetes Mellitus, Type 2 psychology
- Abstract
Background: Depression in patients with diabetes is associated with poorer adherence and worse health outcomes, however treating depression may help improve these outcomes., Objective: The present systematic review identified published papers to evaluate treatments for depression in patients with diabetes., Results: Seventeen studies that met criteria were identified, indicating that psychosocial interventions, particularly cognitive-behavior therapy, anti-depressant medications, and collaborative care are effective in the treatment of depression in patients with diabetes., Conclusion: Evidence for the efficacy of these interventions in improving glycemic control was mixed. No study targeted adherence to treatment or health behaviors in addition to depression, which may be necessary to maximize improvement in diabetes outcomes such as glycemic control., (Copyright © 2011 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.)
- Published
- 2011
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26. Anatomy of discordant atrioventricular connections.
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Wilkinson JL and Anderson RH
- Abstract
The term discordant atrioventricular connections refers to the situation in which the ventricles are connected inappropriately to the atrial chambers. In most instances, the connections of the great arteries are also abnormal, with the aorta and the pulmonary trunk arising from morphologically inappropriate ventricles. This combination results in the presence of so-called congenitally corrected transposition. Double-outlet right ventricle is occasionally present, while concordant ventriculoarterial connections may be seen rarely. Most such hearts have a range of additional abnormalities, including ventricular septal defects; outflow tract obstruction, usually of the morphologically left ventricle; anomalies of the morphologically tricuspid valve; and a highly abnormal location of the specialized atrioventricular conduction axis. Some examples exhibit bizarre abnormalities of ventricular relationships and topology, including criss-cross atrioventricular connections and superoinferior ventricular relations. In describing the anatomy of these malformations, it is important to use a step-by-step segmental approach to the documentation of the connections and associated defects in each case and to avoid potentially confusing shorthand terms.
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- 2011
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27. Reference place conditioning procedure with cocaine: increased sensitivity for measuring associatively motivated choice behavior in rats.
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Reichel CM, Wilkinson JL, and Bevins RA
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- Animals, Cocaine administration & dosage, Dose-Response Relationship, Drug, Injections, Intraperitoneal, Male, Rats, Rats, Sprague-Dawley, Reference Standards, Reward, Choice Behavior drug effects, Cocaine pharmacology, Conditioning, Operant drug effects, Motivation
- Abstract
Place conditioning is widely used to study the conditioned rewarding effects of drugs. In the standard version, one reward (cocaine) is compared with no reward (saline). A modified variant of this task, 'reference-conditioning' procedure, compares two potentially rewarding stimuli (high vs. low cocaine dose). There has been little research on the utility of this procedure. Experiment 1 used the standard protocol with saline administered before confinement to the reference compartment of a place conditioning chamber. On alternate days, saline, 2.5, 5, 7.5, 10, or 20 mg/kg cocaine was administered before confinement to the opposite compartment. In experiments 2 and 3, reference-compartment saline was replaced with 5 and 7.5 mg/kg cocaine, respectively. Relative to saline, 7.5-20 mg/kg cocaine had comparable conditioned rewarding effects (i.e. similar increase in time in paired compartment). When cocaine replaced saline, there was competition at doses lower than 7.5 mg/kg. Rats that received 7.5 versus 2.5 mg/kg spent similar time in each compartment, indicating competition. Competition was not seen with 5 versus 20 mg/kg; preference was for the 20 mg/kg compartment. Experiment 4 showed that the competition at 2.5 mg/kg was not due to reward sensitization. The reference-conditioning procedure has increased the sensitivity for measuring associatively motivated choice behavior.
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- 2010
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28. An investigation of bupropion substitution for the interoceptive stimulus effects of nicotine.
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Wilkinson JL, Carroll FI, and Bevins RA
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- Analysis of Variance, Animals, Behavior, Animal drug effects, Benzazepines pharmacology, Dopamine Uptake Inhibitors pharmacology, Dose-Response Relationship, Drug, Drug Interactions, Male, Motor Activity drug effects, Nicotinic Agonists pharmacology, Rats, Rats, Sprague-Dawley, Receptors, Dopamine D1 antagonists & inhibitors, Receptors, Dopamine D1 metabolism, Bupropion pharmacology, Discrimination Learning drug effects, Nicotine pharmacology
- Abstract
Although the exact mechanism that makes bupropion hydrochloride (Zyban) effective as a smoking cessation aid has not been fully elucidated, studies have found that bupropion and nicotine share behavioural and neurophysiological properties suggesting that bupropion might serve as a substitute for nicotine. In fact, bupropion prompts nicotine-appropriate responding in operant and Pavlovian drug discrimination studies with rats. A majority of the literature examining this substitution pattern has been done with an operant paradigm. The present research extended this literature by further characterising the behavioural and neuropharmacological properties underlying the substitution for a nicotine conditioned stimulus (CS). Examination of the dose-effect function and temporal dynamics of this substitution pattern showed that bupropion (20 mg/kg) produced conditioned responding similar to nicotine (0.4 mg base/kg) (ED(50) = 9.9 mg/kg) at 15 and 30 min after injection and partially substituted 5 and 60 min post-injection. Bupropion produced a pattern of conditioned responding similar to nicotine during a 60-min extinction test. Additionally, it has been hypothesised that bupropion and nicotine have an overlapping dopaminergic mechanism. We tested the effects of bupropion pretreatment, the nicotine dose-effect function and the ability of dopamine antagonist to block the substitution of bupropion for nicotine. Pretreatment with doses of bupropion that did not substitute for the nicotine stimulus (5 and 10 mg/kg) did not affect nicotine-conditioned responding; pretreatment with 20 mg/kg attenuated nicotine-evoked responding. Pretreatment with the dopamine antagonists SCH-23390 and eticlopride blocked the substitution. Finally, S,S-hydroxybupropion, the major metabolite of bupropion in humans, did not substitute for the nicotine CS.
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- 2010
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29. Mecamylamine, dihydro-beta-erythroidine, and dextromethorphan block conditioned responding evoked by the conditional stimulus effects of nicotine.
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Struthers AM, Wilkinson JL, Dwoskin LP, Crooks PA, and Bevins RA
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- Animals, Conditioning, Psychological physiology, Male, Rats, Rats, Sprague-Dawley, Receptors, Nicotinic physiology, Conditioning, Psychological drug effects, Dextromethorphan pharmacology, Dihydro-beta-Erythroidine pharmacology, Mecamylamine pharmacology, Nicotine antagonists & inhibitors, Nicotine pharmacology
- Abstract
Current smokers express the desire to quit. However, the majority find it difficult to remain abstinent. As such, research efforts continually seek to develop more effective treatment. One such area of research involves the interoceptive stimulus effects of nicotine as either a discriminative stimulus in an operant drug discrimination task, or more recently as a conditional stimulus (CS) in a discriminated goal-tracking task. The present work investigated the potential role nicotinic acetylcholine receptors play in the CS effects of nicotine (0.4mg/kg) using antagonists with differential selectivity for beta2*, alpha7*, alpha6beta2*, and alpha3beta4* receptors. Methyllycaconitine (MLA) had no effect on nicotine-evoked conditioned responding. Mecamylamine and dihydro-beta-erythroidine (DHbetaE) dose-dependently blocked responding evoked by the nicotine CS. In a time-course assessment of mecamylamine and DHbetaE, each blocked conditioned responding when given 5min before testing and still blocked conditioned responding when administered 200min before testing. Two novel bis-picolinium analogs (N, N'-(3, 3'-(dodecan-1,12-diyl)-bis-picolinium dibromide [bPiDDB], and N, N'-(decan-1,10-diyl)-bis-picolinium diiodide [bPiDI]) did not block nicotine-evoked conditioned responding. Finally, pretreatment with low dose combinations of mecamylamine, dextromethorphan, and/or bupropion was used to target alpha3beta4* receptors. No combination blocked conditioned responding evoked by the training dose of nicotine. However, a combination of mecamylamine and dextromethorphan partially blocked nicotine-evoked conditioned responding to a lower dose of nicotine (0.1mg/kg). These results indicate that beta2* and potentially alpha3beta4* nicotinic acetylcholine receptors play a role in the CS effects of nicotine and are potential targets for the development of nicotine cessation aids.
- Published
- 2009
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30. Pavlovian drug discrimination with bupropion as a feature positive occasion setter: substitution by methamphetamine and nicotine, but not cocaine.
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Wilkinson JL, Li C, and Bevins RA
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- Bupropion administration & dosage, Cocaine administration & dosage, Dopamine Uptake Inhibitors administration & dosage, Humans, Methamphetamine administration & dosage, Nicotine administration & dosage, Peritoneum, Bupropion pharmacology, Cocaine pharmacology, Conditioning, Classical, Discrimination Learning drug effects, Dopamine Uptake Inhibitors pharmacology, Methamphetamine pharmacology, Nicotine pharmacology
- Abstract
Bupropion can serve as a discriminative stimulus (S(D)) in an operant drug discrimination task, and a variety of stimulants substitute for the bupropion S(D). There are no reports, however, of bupropion functioning as a Pavlovian occasion setter (i.e. feature positive modulator). The present experiment seeks to fill this gap in the literature by training bupropion in rats as a feature positive modulator that disambiguates when a light will be paired with sucrose. Specifically, on bupropion (10 mg/kg intraperitoneal) sessions, offset of 15-second cue lights were followed by brief delivery of liquid sucrose; saline sessions were similar except no sucrose was available. Rats readily acquired the discrimination with more conditioned responding to the light on bupropion sessions. Bupropion is approved for use as a smoking cessation aid, and more recently has drawn attention as a potential pharmacotherapy for cocaine and methamphetamine abuse. Accordingly, after discrimination training, we tested the ability of cocaine (1-10 mg/kg), methamphetamine (0.1 to 1 mg/kg) and nicotine (0.00625 to 0.2 mg/kg) to substitute for the bupropion feature. Nicotine (0.05 mg/kg) and methamphetamine (0.3 mg/kg) substituted fully for bupropion; cocaine did not substitute. These results extend previous research on shared stimulus properties between bupropion and other stimulants to a Pavlovian occasion setting function. Further, this is the first report of nicotine and methamphetamine substitution for bupropion. The overlap in stimulus properties might explain the effectiveness of bupropion as a smoking cessation aid and highlight the possible utility of bupropion for treatment of stimulant use disorder.
- Published
- 2009
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31. Initial results of primary device closure of large muscular ventricular septal defects in early infancy using perventricular access.
- Author
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Crossland DS, Wilkinson JL, Cochrane AD, d'Udekem Y, Brizard CP, and Lane GK
- Subjects
- Echocardiography, Transesophageal, Female, Heart Failure diagnostic imaging, Heart Failure etiology, Heart Septal Defects, Ventricular complications, Heart Septal Defects, Ventricular diagnostic imaging, Heart Ventricles surgery, Humans, Infant, Infant, Newborn, Retrospective Studies, Treatment Outcome, Ultrasonography, Interventional, Cardiac Surgical Procedures instrumentation, Heart Failure surgery, Heart Septal Defects, Ventricular surgery
- Abstract
Objectives: To report our experience with the use of the Amplatzer muscular ventricular septal defect (VSD) occluder, using direct right ventricle free wall puncture for primary closure of muscular VSDs in infants., Background: Young infants with heart failure due to large or multiple muscular VSDs often require intervention at a stage when percutaneous device closure is impractical due to delivery system limitations. There are considerable benefits to avoiding bypass in these infants., Methods: Patients with suitable muscular VSDs, considered too small for transvenous closure, underwent periventricular muscular VSD closure under transesophageal echo (TEE) guidance., Results: Eight infants underwent the procedure. The median age was 14 weeks (2-41) with median weight of 4 kg (3-6.6). Four patients had additional VSDs and one patient had previous repair of coarctation. One patient had dextrocardia and severe left ventricular impairment due to an associated cardiomyopathy. The median VSD size was 8 mm (range, 4-10 mm). A single device (6-12 mm) was deployed in each patient, the size chosen being 1-2 mm larger than the TEE measurement. Two patients had subsequent pulmonary artery banding, with absorbable bands, because of moderate residual shunting through additional VSDs. The latest echo study at a median of 7.2 weeks (0.5-66) post device implantation revealed no patients with a hemodynamically significant shunt., Conclusion: Perventricular muscular VSD closure can be safely and effectively undertaken in small infants with suitable muscular defects, and this strategy can avoid the need for bypass., (Copyright 2008 Wiley-Liss, Inc.)
- Published
- 2008
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32. Aortic translocation, Senning procedure and right ventricular outflow tract augmentation for congenitally corrected transposition, ventricular septal defect and pulmonary stenosis.
- Author
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Davies B, Oppido G, Wilkinson JL, and Brizard CP
- Subjects
- Child, Humans, Male, Pulmonary Artery transplantation, Reoperation, Transplantation, Autologous, Transplantation, Homologous, Aorta surgery, Heart Septal Defects, Ventricular surgery, Pulmonary Valve Stenosis surgery, Transposition of Great Vessels surgery
- Abstract
The management of congenitally corrected transposition of the great arteries and associated lesions is frequently challenging. Significant pulmonary stenosis is a contraindication to the conventional double-switch. Instead repair may be accomplished by the Rastelli-Senning procedure, using an extracardiac conduit to achieve continuity between the morphological left ventricle and the pulmonary arteries. This however can be accompanied by conduit and intra-ventricular baffle-related problems that can necessitate surgical re-intervention and lead to late mortality. We describe the use of aortic translocation, Senning procedure and reconstruction of the right ventricular outflow tract using autologous tissue and valved homograft to facilitate anatomical correction in congenitally corrected transposition. The advantages of this technique in this group of patients and the implications for conduction tissue are discussed.
- Published
- 2008
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33. Vaccines to combat smoking.
- Author
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Bevins RA, Wilkinson JL, and Sanderson SD
- Subjects
- Drug Design, Humans, Smoking immunology, Smoking Prevention, Antibodies blood, Nicotine immunology, Nicotinic Agonists immunology, Smoking therapy, Smoking Cessation methods, Vaccines
- Abstract
Background: Current US FDA-approved biological therapies for treating smoking target central nervous system processes. Although these therapies have had some success, relapse within a year is still high. Clearly additional strategies are needed to aid individuals in maintaining abstinence., Objective/methods: We briefly discuss promising research using vaccines to combat smoking and then identify some potentially important directions for future research., Results/conclusions: Immunization with a nicotine vaccine generates drug-specific antibodies that sequester some of the nicotine in the peripheral circulation preventing it from entering the brain, thus decreasing its addictive effects. Albeit promising, much more research is necessary to identify more efficacious vaccine designs and formulations, as well as optimal immunization regimens. A further understanding of the factors contributing to the substantial individual differences in immunogenicity to these vaccines and how to best use vaccines in combination with other treatment strategies will increase the success of intervention efforts.
- Published
- 2008
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34. Intravenous nicotine conditions a place preference in rats using an unbiased design.
- Author
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Wilkinson JL and Bevins RA
- Subjects
- Animals, Data Interpretation, Statistical, Dose-Response Relationship, Drug, Injections, Intravenous, Male, Motor Activity drug effects, Nicotine administration & dosage, Nicotinic Agonists administration & dosage, Rats, Rats, Sprague-Dawley, Tobacco Use Disorder psychology, Conditioning, Operant drug effects, Nicotine pharmacology, Nicotinic Agonists pharmacology
- Abstract
The rewarding effects of nicotine contribute to the chronic use of tobacco products. The place conditioning task, a widely used pre-clinical model to study drug reward, has lead to mixed results in rats when nicotine was administered subcutaneously or intraperitoneally; intravenously administered nicotine has not been examined. Further, much of the research demonstrating a nicotine-conditioned place preference in rats has used a biased design making these results susceptible to non-reward interpretations. The present study assessed whether intravenous (IV) nicotine would condition a place preference in an unbiased design and evaluated important behavioral parameters: nicotine dose, number of conditioning trials, and infusion-to-placement interval. In adult male Sprague Dawley rats, IV nicotine (0.03 mg/kg) conditioned a place preference after 8 conditioning trials. This conditioned preference was observed whether nicotine was infused 10 min before or immediately after placement in the paired environment for 10 min; infusing nicotine immediately after removal from the paired environment did not condition a preference after 4 or 8 conditioning trials. Four conditioning trials were not sufficient to condition a preference regardless of the temporal relation between the paired environment and 0.03 mg/kg nicotine. A 0.01 mg/kg dose of nicotine did not condition a place preference after 4 or 8 trials when infused immediately upon placement in the paired environment. Intravenous nicotine (0.03 mg/kg) has rewarding effects in an unbiased design suggesting that the place conditioning protocol used in the present study might be an especially useful model for studying the processes underlying the conditioned rewarding effects of nicotine.
- Published
- 2008
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35. Methamphetamine functions as a positive and negative drug feature in a Pavlovian appetitive discrimination task.
- Author
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Reichel CM, Wilkinson JL, and Bevins RA
- Subjects
- Animals, Bupropion pharmacology, Cocaine pharmacology, Conditioning, Classical drug effects, Male, Naloxone pharmacology, Rats, Rats, Sprague-Dawley, Discrimination Learning drug effects, Methamphetamine pharmacology
- Abstract
This research determined the ability of methamphetamine to serve as a positive or negative feature, and assessed the ability of bupropion, cocaine, and naloxone to substitute for the methamphetamine features. Rats received methamphetamine (0.5 mg/kg, intraperitoneally) or saline 15 min before a conditioning session. For the feature positive (FP) group, offset of 15-s cue lights was followed by access to sucrose on methamphetamine sessions; sucrose was withheld during saline sessions. For the feature negative (FN) group, the light offset was followed by sucrose on saline sessions; sucrose was withheld during methamphetamine sessions. During acquisition, the FP group had higher responding on methamphetamine sessions than on saline sessions. For the FN group, responding was higher on saline sessions than on methamphetamine sessions. Conditioned responding was sensitive to methamphetamine dose. For the FP group, bupropion and cocaine fully and partially substituted for methamphetamine, respectively. In contrast, both drugs fully substituted for methamphetamine in the FN group. Naloxone did not substitute in either set of rats. FP-trained rats were more sensitive to the locomotor stimulating effects of the test drugs than FN-trained rats. This research demonstrates that the pharmacological effects of methamphetamine function as a FP or FN in this Pavlovian discrimination task and that training history can affect conditioned responding and locomotor effects evoked by a drug.
- Published
- 2007
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36. Transcatheter closure of perimembranous ventricular septal defect.
- Author
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Dumitrescu A, Lane GK, Wilkinson JL, Goh TH, Penny DJ, and Davis AM
- Subjects
- Humans, Pacemaker, Artificial, Balloon Occlusion adverse effects, Heart Block etiology, Heart Septal Defects, Ventricular therapy
- Published
- 2007
- Full Text
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37. Bupropion hydrochloride produces conditioned hyperactivity in rats.
- Author
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Wilkinson JL and Bevins RA
- Subjects
- Analysis of Variance, Animals, Antidepressive Agents, Second-Generation pharmacology, Dose-Response Relationship, Drug, Exploratory Behavior drug effects, Male, Random Allocation, Rats, Rats, Sprague-Dawley, Association Learning drug effects, Behavior, Animal drug effects, Bupropion pharmacology, Central Nervous System Stimulants pharmacology, Conditioning, Classical drug effects, Hyperkinesis chemically induced
- Abstract
Bupropion is marketed as an antidepressant, Wellbutrin and smoking cessation aid, Zyban. Although the therapeutic neurological mechanisms of bupropion have not been fully elucidated, bupropion shares some behavioral similarities with classic psychomotor stimulants. The present study sought to further investigate these psychomotor stimulant effects of bupropion by assessing whether repeated administration of bupropion in a distinct environment produced conditioned hyperactivity. Paired rats received 10 daily i.p. injections of bupropion (2.5-30 mg/kg) before placement in locomotor chambers for 30 min. Bupropion (10-30 mg/kg) produced acute locomotor hyperactivity compared to Unpaired controls. After repeated administration, there was no progressive increase or decrease in bupropion-induced activity. In a subsequent drug-free session conditioned hyperactivity was observed at 5-30 mg/kg doses. In a follow-up experiment, we examined whether responsiveness to novelty predicted the subsequent unconditioned and conditioned locomotor effect of bupropion. Reactivity to inescapable novelty, novel environment approach, and novel-object interaction were measured before locomotor conditioning with 30 mg/kg bupropion. We replicated the previous experiment, but scores on the novelty screens did not predict locomotor response to bupropion. This study extends the literature by demonstrating that environmental cues repeatedly paired with the stimulant effects of bupropion come to evoke elevated activity in the absence of drug (i.e., conditioned hyperactivity). This finding is consistent with the literature suggesting that bupropion shares many behavioral similarities with other psychomotor stimulants which also produce conditioned hyperactivity. However, a predictive relation between reactivity to forced novelty and the subsequent locomotor effect of bupropion may not be one of these similarities.
- Published
- 2007
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38. The early history of paediatric cardiology in the United Kingdom, with specific reference to KD Wilkinson.
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Wilkinson JL and Anderson RH
- Subjects
- Electrocardiography history, Heart Defects, Congenital diagnosis, Heart Defects, Congenital history, History, 20th Century, Humans, United Kingdom, Cardiology history, Pediatrics history
- Published
- 2007
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39. Paediatric cardiology--James William Brown.
- Author
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Wilkinson JL, Gerlis LM, and Anderson RH
- Subjects
- England, Heart Defects, Congenital history, History, 20th Century, Humans, Male, Cardiology history, Pediatrics history
- Published
- 2007
- Full Text
- View/download PDF
40. Angiographic diagnosis, prevalence and outcomes for left ventricular noncompaction in children with congenital cardiac disease.
- Author
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Hughes ML, Carstensen B, Wilkinson JL, and Weintraub RG
- Subjects
- Adolescent, Australia epidemiology, Child, Child, Preschool, Female, Heart Defects, Congenital mortality, Heart Defects, Congenital therapy, Heart Transplantation, Humans, Infant, Male, Proportional Hazards Models, Retrospective Studies, Survival Rate, Ventricular Dysfunction, Left mortality, Ventricular Dysfunction, Left therapy, Coronary Angiography, Heart Defects, Congenital diagnostic imaging, Ventricular Dysfunction, Left diagnostic imaging
- Abstract
Little is known about the implications of left ventricular noncompaction in children with additional congenital cardiac malformations. With this in mind, we conducted a retrospective review of every left ventricular angiogram performed in a single tertiary referral centre for paediatric cardiology, in Melbourne, Australia, between 1994 and 2000 in children with congenital heart disease, looking specifically for patients with angiographic evidence of noncompaction of the left ventricle. The outcome of patients identified as having noncompaction was compared with that of patients from the same population, stratified by their primary congenital cardiac malformation. Of 1515 children undergoing left ventricular angiography, 31, with 13 being male, were found to have angiographic evidence of left ventricular noncompaction, giving a prevalence of 2% (95% CI: 1.3%-2.8%). Of 69 (22%) children with a functionally single left ventricle, 15 fulfilled the criterions for noncompaction, compared to 16 of 1446 (1.1%) children with a balanced ventricular arrangement (p is less than 0.0001). The presence of noncompaction and a functionally single left ventricle were each associated with a doubling of mortality, the effect being cumulative. Of surviving patients with left ventricular noncompaction, 19% (4%-34%) have left ventricular dysfunction at their latest follow-up. We suggest that the important late sequels of noncompaction justify careful scrutiny for this entity in children with congenital cardiac disease.
- Published
- 2007
- Full Text
- View/download PDF
41. The diverse cardiac morphology seen in hearts with isomerism of the atrial appendages with reference to the disposition of the specialised conduction system.
- Author
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Smith A, Ho SY, Anderson RH, Connell MG, Arnold R, Wilkinson JL, and Cook AC
- Subjects
- Atrial Appendage innervation, Cadaver, Fetal Heart abnormalities, Fetal Heart innervation, Heart Ventricles innervation, Heart Ventricles pathology, Humans, Atrial Appendage abnormalities, Atrioventricular Node abnormalities, Heart Defects, Congenital pathology
- Abstract
Congenital cardiac malformations which include isomerism of the atrial appendages are amongst the most challenging of problems for diagnosis and also for medical and surgical management. The nomenclature for pathological description is controversial, but difficulties can be overcome by the use of a segmental approach. Such an approach sets out the morphology and the topology of the chambers of the heart, together with the types and modes of the atrioventricular, ventriculo-arterial, and venous connections. We have applied this method to a study of 35 hearts known to have isomerism of the atrial appendages. We have already published accounts of 27 of these cases, but these were reviewed for this study in the light of our increased awareness of the implications of isomerism, and 8 new cases were added. After examining, or re-examining, the morphology of every heart in detail, we grouped them together according to their ventricular topology and modes of atrioventricular connection. Then we studied the course of the specialised conduction system, by the use of the light microscope, first in each individual case, and then together in their groups. We conclude that the pathways for atrioventricular conduction in hearts with isomerism of the atrial appendages are conditioned both by ventricular topology, and by the atrioventricular connections. Based on our experience, we have been able to establish guidelines that direct the clinician to the likely location of the conduction tissues.
- Published
- 2006
- Full Text
- View/download PDF
42. The nomenclature, definition and classification of discordant atrioventricular connections.
- Author
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Jacobs JP, Franklin RC, Wilkinson JL, Cochrane AD, Karl TR, Aiello VD, Béland MJ, Colan SD, Elliott MJ, Gaynor JW, Krogmann ON, Kurosawa H, Maruszewski B, Stellin G, Tchervenkov CI, and Weinberg PM
- Subjects
- Cardiac Surgical Procedures methods, Humans, Transposition of Great Vessels diagnosis, Transposition of Great Vessels surgery, Terminology as Topic, Transposition of Great Vessels classification
- Abstract
During the process of creation of a bidirectional crossmap between the system emerging, on the one hand, from the initiative sponsored by the Congenital Heart Committees of the European Association for Cardio-Thoracic Surgery and the Society of Thoracic Surgeons, and on the other hand, from that formulated by the Coding Committee of the European Association for Pediatric Cardiology, the Nomenclature Working Group has successfully created the International Paediatric and Congenital Cardiac Code. As would be expected, during the process of crossmapping it became clear that, for most lesions, the European Pediatric Cardiac Code was more complete in its description of the diagnoses, while the International Congenital Heart Surgery Nomenclature and Database Project was more complete in its description of the procedures. This process of crossmapping exemplifies the efforts of the Nomenclature Working Group to create a comprehensive and all-inclusive international system for the naming of paediatric and congenital cardiac disease, the International Pediatric and Congenital Cardiac Code. Although names and classification for paediatric and congenital cardiac disease will continue to evolve over time, we are now closer than ever to reaching uniform international agreement and standardization. The International Paediatric and Congenital Cardiac Code can be downloaded from the Internet, free of charge, at www.ipccc. net.
- Published
- 2006
- Full Text
- View/download PDF
43. Concordant ventriculoarterial connections with parallel arterial trunks in the setting of isomerism of the right atrial appendages.
- Author
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Crossland DS, Anderson RH, and Wilkinson JL
- Subjects
- Abnormalities, Multiple, Autopsy, Coronary Vessel Anomalies pathology, Dextrocardia pathology, Fatal Outcome, Heart Septal Defects, Ventricular pathology, Heart Ventricles abnormalities, Humans, Infant, Newborn, Male, Pulmonary Veins abnormalities, Transposition of Great Vessels pathology, Vena Cava, Superior abnormalities, Atrial Appendage abnormalities, Heart Defects, Congenital pathology
- Abstract
We describe an autopsied specimen, from an infant who died in 1967, in which concordant ventriculoarterial connections coexisted with parallel arterial trunks, usually described as "anatomically corrected malposition." Based on their shape, the extent of the pectinate muscles, and the absence of a coronary sinus, we diagnosed isomeric right atrial appendages. Despite this, the arrangement of the remaining thoracic and abdominal organs, as well as the patterns of venous drainage, was almost completely mirror imaged.
- Published
- 2006
- Full Text
- View/download PDF
44. Interoceptive Pavlovian conditioning with nicotine as the conditional stimulus varies as a function of the number of conditioning trials and unpaired sucrose deliveries.
- Author
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Wilkinson JL, Murray JE, Li C, Wiltgen SM, Penrod RD, Berg SA, and Bevins RA
- Subjects
- Animals, Discrimination Learning drug effects, Extinction, Psychological drug effects, Male, Rats, Rats, Sprague-Dawley, Conditioning, Classical drug effects, Nicotine pharmacology, Nicotinic Agonists pharmacology, Sucrose pharmacology
- Abstract
In rats, the pharmacological (interoceptive) effects of nicotine can serve as a signal (conditional stimulus) in a Pavlovian (classical) conditioning task. In this task, nicotine administration (0.4 mg base/kg, subcutaneous) is typically paired with intermittent access to a liquid sucrose unconditional stimulus; sucrose is withheld on saline sessions. An increase in sucrose receptacle entries (goal tracking) on nicotine sessions indicates conditioning. Given our limited understanding of the functional relationships controlling conditioned responding to a nicotine conditional stimulus, the present research examined nicotine's sensitivity to several manipulations shown to affect the conditioned responding in more widely studied Pavlovian conditioning tasks that use exteroceptive conditional stimuli: number of nicotine conditional stimulus-sucrose unconditional stimulus pairings per session (0, 3, 9, 18, or 36) and the impact of sucrose deliveries in saline sessions. Differential goal tracking developed in fewer sessions and asymptotic conditioned responding magnitude was greater with more nicotine-sucrose pairings. Further, goal tracking was more resistant to extinction (unconditional stimulus withheld) with more conditional-unconditional stimulus pairings during the acquisition phase. The discrimination was not acquired when sucrose presentations (9 or 18) also occurred during saline sessions. Furthermore, expression of the discrimination was disrupted when sucrose was presented in saline sessions; this disruption resulted from goal tracking in saline sessions. These results are consistent with the notion that nicotine-evoked goal tracking results from interoceptive conditioning processes.
- Published
- 2006
- Full Text
- View/download PDF
45. Characterization of nicotine's ability to serve as a negative feature in a Pavlovian appetitive conditioning task in rats.
- Author
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Bevins RA, Wilkinson JL, Palmatier MI, Siebert HL, and Wiltgen SM
- Subjects
- Amphetamine pharmacology, Animals, Arecoline pharmacology, Association Learning drug effects, Bupropion pharmacology, Caffeine pharmacology, Chlordiazepoxide pharmacology, Discrimination Learning drug effects, Dose-Response Relationship, Drug, Drug Interactions, Hexamethonium pharmacology, Male, Mecamylamine pharmacology, Motor Activity drug effects, Nicotinic Agonists pharmacology, Nicotinic Antagonists pharmacology, Nucleus Accumbens drug effects, Rats, Rats, Sprague-Dawley, Receptors, Nicotinic drug effects, Sucrose administration & dosage, Conditioning, Classical drug effects, Conditioning, Operant drug effects, Nicotine pharmacology, Reinforcement, Psychology
- Abstract
Rationale: Pavlovian feature negative discriminations have been widely used to understand inhibitory conditioning processes using exteroceptive stimuli. Comparatively little is known about inhibitory conditioning processes using a drug state as a negative feature. A negative feature signals that presentation of a conditional stimulus (CS) will not be paired with an unconditioned stimulus., Objectives: The present research examined whether nicotine served as a negative feature and started characterizing its properties., Methods and Results: In acquisition, rats received intermixed saline and nicotine (0.4 mg/kg, base) sessions. On saline sessions, a 15-s light CS was paired with 4-s access to sucrose; the CS was presented on nicotine sessions, but sucrose was withheld. The discrimination was acquired with more goal tracking during the CS on saline sessions. Nicotine's inhibition of this conditioned response (CR) was sensitive to nicotine dose (ED50=0.225) and injection to testing interval (CR returned at 200 min). Mecamylamine pretreatment, but not hexamethonium, produced a loss of inhibitory control by nicotine suggesting a role for central nicotinic acetylcholine receptors. Amphetamine, bupropion, arecoline, and chlordiazepoxide, but not caffeine, substituted for the nicotine feature. However, in locomotor tests, amphetamine and bupropion increased activity; arecoline and chlordiazepoxide decreased activity. For this reason, the motor effects of these ligands could not be dissociated from substitution via shared stimulus properties., Conclusions: This feature negative task provides a preclinical model for studying how drug states inhibit responding, although identifying the process(es) mediating CR inhibition will require further research.
- Published
- 2006
- Full Text
- View/download PDF
46. Preexposure to nicotine alters the subsequent locomotor stimulant effects of bupropion in rats.
- Author
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Wilkinson JL, Palmatier MI, and Bevins RA
- Subjects
- Animals, Behavior, Animal drug effects, Central Nervous System Stimulants administration & dosage, Disease Models, Animal, Male, Nicotine administration & dosage, Random Allocation, Rats, Rats, Sprague-Dawley, Bupropion metabolism, Bupropion therapeutic use, Central Nervous System Stimulants pharmacology, Dopamine Uptake Inhibitors metabolism, Dopamine Uptake Inhibitors therapeutic use, Locomotion drug effects, Nicotine pharmacology
- Abstract
Little is known about the interaction between nicotine and bupropion (Zyban), but many studies suggest they have neurological and behavioral similarities. One feature of drugs with common profiles is the ability to cross-sensitize possibly through neurological changes in the reward pathway. Activation of this pathway might explain the effectiveness of bupropion as a smoking cessation aid. The present research investigated whether repeated nicotine administration altered the subsequent locomotor effects of bupropion. In experiment 1, rats were preexposed to nicotine (0.4 mg/kg subcutaneously) or saline on eight separate occasions in the home cage and then tested with bupropion (0, 20, or 30 mg/kg) in locomotor chambers. The acute stimulant effect of 30 mg/kg of bupropion was potentiated by nicotine preexposure. In experiment 2, rats received nicotine repeatedly paired with the locomotor chambers or home cages. An additive effect was observed between acute bupropion and nicotine-conditioned hyperactivity in the chamber-paired group. This enhancement of the acute locomotor effects of bupropion might reflect alterations in common dopaminergic processes.
- Published
- 2006
- Full Text
- View/download PDF
47. Pulmonary atresia with ventricular septal defects and major aortopulmonary collateral arteries: unifocalization brings no long-term benefits.
- Author
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d'Udekem Y, Alphonso N, Nørgaard MA, Cochrane AD, Grigg LE, Wilkinson JL, and Brizard CP
- Subjects
- Adolescent, Adult, Cardiac Surgical Procedures methods, Child, Child, Preschool, Female, Follow-Up Studies, Humans, Infant, Infant, Newborn, Male, Neovascularization, Pathologic complications, Neovascularization, Pathologic surgery, Time Factors, Vascular Surgical Procedures methods, Abnormalities, Multiple surgery, Aorta, Thoracic abnormalities, Aorta, Thoracic surgery, Heart Septal Defects, Ventricular complications, Heart Septal Defects, Ventricular surgery, Pulmonary Artery abnormalities, Pulmonary Artery surgery, Pulmonary Atresia complications, Pulmonary Atresia surgery
- Abstract
Objectives: We sought to evaluate the contribution of unifocalization procedures in the management of patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries., Methods: From 1975 through 1995, 82 consecutive patients were entered in a multistage approach and had 189 sternotomies and thoracotomies to perform 119 shunts, 130 major aortopulmonary collateral artery transplantations, and 76 major aortopulmonary collateral artery ligations. The serial angiographies and the follow-up of these patients were reviewed., Results: The concurrent follow-up rate was 80%. The hospital mortality of the preliminary procedures was 4% (7/189). Fifty-three (65%) patients had a complete repair. The hospital mortality of the repair was 8% (4/53), and 9 late deaths occurred after repair, all of which were cardiac related. The overall survival of all patients to the age of 30 years was 58% +/- 7%. Survival 12 years after complete repair was 51% +/- 14%. On angiography, central shunts promoted growth of central pulmonary arteries in all cases (29 patients). Sixty unifocalized major aortopulmonary collateral arteries were identified in 31 patients. After a mean of 3.2 +/- 4 years, 26 thrombosed, and 12 presented with a stenosis of greater than 50%. Serial measurements of 29 major aortopulmonary collateral arteries showed no signs of growth (P = .25)., Conclusion: Long-term survival into adulthood of patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries has been achieved with a multistage approach. However, late survival depends exclusively on the growth of the native pulmonary circulation. The few unifocalized major aortopulmonary collateral arteries that did not thrombose failed to grow.
- Published
- 2005
- Full Text
- View/download PDF
48. Reconstruction of left main coronary artery with subclavian artery free graft in an infant.
- Author
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Guerrero RR, Wilkinson JL, and Brizard CP
- Subjects
- Aorta surgery, Female, Graft Occlusion, Vascular, Humans, Infant, Mitral Valve surgery, Reoperation, Coronary Vessel Anomalies surgery, Coronary Vessels, Subclavian Artery transplantation
- Abstract
We report the case of a 3-month-old infant with anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) with absent left main coronary artery (LMCA). She underwent repair by reimplantation technique with the construction of a short LMCA using two opposite flaps. Two months later she was re-admitted in cardiac failure. Occlusion of the reconstructed LMCA was found by angiogram. At reoperation the right subclavian artery was used as a free interposition graft to reconstruct the LMCA. The post-operative course was uneventful. At 8 months she was asymptomatic and LMCA patency was demonstrated by angiogram.
- Published
- 2005
- Full Text
- View/download PDF
49. Stimulus properties of nicotine, amphetamine, and chlordiazepoxide as positive features in a pavlovian appetitive discrimination task in rats.
- Author
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Palmatier MI, Wilkinson JL, Metschke DM, and Bevins RA
- Subjects
- Amphetamine pharmacology, Animals, Brain drug effects, Brain metabolism, Brain physiopathology, Caffeine pharmacology, Central Nervous System Stimulants pharmacology, Chlordiazepoxide pharmacology, Cues, Discrimination Learning physiology, Dose-Response Relationship, Drug, Drug Interactions physiology, Generalization, Stimulus drug effects, Generalization, Stimulus physiology, Hypnotics and Sedatives pharmacology, Male, Nicotine pharmacology, Nicotinic Agonists pharmacology, Rats, Rats, Sprague-Dawley, Substance-Related Disorders physiopathology, Appetitive Behavior drug effects, Conditioning, Classical drug effects, Discrimination Learning drug effects, Illicit Drugs pharmacology, Reward, Substance-Related Disorders metabolism
- Abstract
Recent experiments from our laboratory have demonstrated that drug states can signal when environmental cues will be followed by rewarding outcomes (ie Pavlovian conditioning). However, little is known about the generality of this approach and whether it can be used for studying the pharmacological properties of drug states. Accordingly, the present experiments tested the pharmacological specificity of nicotine (0.4 mg/kg), amphetamine (1 mg/kg), and chlordiazepoxide (CDP, 5 mg/kg) in this Pavlovian drug discrimination procedure. Following drug administration, presentation of a conditional stimulus (CS) was followed by brief access to sucrose. When saline was administered, the same CS was presented but sucrose was withheld. In substitution tests, rats in each condition received varying doses of all training drugs and caffeine. Anticipatory food seeking developed during the CS on drug sessions but not on saline sessions for all drug features (ie drug state-specific conditional response (CR)). In generalization tests, this CR decreased as a function of decreases in the training dose. Median effective doses (ED50s) were calculated for nicotine (0.054 mg/kg), amphetamine (0.26 mg/kg), and CDP (2.48 mg/kg). No compound tested substituted for the CDP training drug. Partial substitution was evident between nicotine and amphetamine; CDP did not substitute for either of these drug features. Caffeine fully substituted for nicotine (ED50 = 15.45 mg/kg) and amphetamine (ED50 = 3.70 mg/kg), but not for CDP. These results are consistent with the hypothesis that drug states can occasion appetitive Pavlovian CRs in a pharmacologically specific manner.
- Published
- 2005
- Full Text
- View/download PDF
50. Angiotensin I converting enzyme genotype affects ventricular remodelling in children with aortic coarctation.
- Author
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Zadinello M, Greve G, Liu XQ, Barbosa JR Jr, Schulze-Neick I, Wilkinson JL, and Redington AN
- Subjects
- Aortic Coarctation enzymology, Female, Genotype, Humans, Infant, Male, Polymorphism, Genetic genetics, Aortic Coarctation surgery, Peptidyl-Dipeptidase A genetics, Ventricular Remodeling genetics
- Published
- 2005
- Full Text
- View/download PDF
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