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Stankovic Z, Semaan E, Markl M, Carr M, Wasielewski M, Lewandowski R, Salem R, Carr J, Collins J. Initiale Ergebnisse einer quantitative Beurteilung der Leberhaemodynamik mittels k-t GRAPPA beschleunigten 4D flow MRT bei Leberzirrhosepatienten. ROFO-FORTSCHR RONTG 2014. [DOI: 10.1055/s-0034-1372838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Topaz O, Morris C, Minisi A, Mohanty P, Carr M. Enhancement of t-PA Induced Fibrinolysis with Laser Energy: In-Vitro Observations. Lasers Med Sci 2014; 14:123-8. [DOI: 10.1007/s101030050033] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Shafer F, Smith L, Vendetti N, Rendo P, Carr M. Lack of seasonal variation in bleeding and patient-assessed pain patterns in patients with haemophilia B receiving on-demand therapy. Haemophilia 2013; 20:349-53. [PMID: 24286226 PMCID: PMC4216408 DOI: 10.1111/hae.12305] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/07/2013] [Indexed: 11/28/2022]
Abstract
Spontaneous haemorrhage in patients with haemophilia is generally considered to occur randomly and without a predictable temporal or seasonal pattern; however, there is a lack of evidence in the literature on the effects of weather, temperature and atmosphere on bleeding episodes. This post hoc analysis of a multicentre, open-label crossover study examined the influence of seasonality on bleeding frequency and patient-assessed pain in patients with moderately severe and severe (FIX C ≤ 2%) haemophilia B. Fifty patients were enrolled and treated on-demand for 16 weeks; 47 were subsequently randomized to one of two prophylactic regimens (nonacog alfa 100 IU kg−1 once weekly or 50 IU kg−1 twice weekly) for 16 weeks. Patients then underwent an 8-week washout period of on-demand therapy before being crossed over to the other prophylactic regimen for 16 weeks. Bleeding episodes during the on-demand treatment periods were analysed. To assess for temporal trends, data were graphed as scatter plots. The primary end point was the annualized bleeding rate (ABR). Additional measures included raw and median pain scores during every joint bleeding event (spontaneous or traumatic), with pain scored using the Brief Pain Inventory (0 = ‘no pain’ to 10 = ‘pain as bad as you can imagine’). The observed ABRs during the on-demand periods showed no distinguishable trend over time. Analysis of pain associated with joint bleeding episodes also did not demonstrate any discernible temporal trend. No apparent seasonal variation in bleeding pattern or patient-reported pain was observed in this analysis of patients with haemophilia B.
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Semaan E, Spottiswoode B, Freed B, Carr M, Wasielewski M, Fortney-Campione K, Shah S, Carr J, Markl M, Collins J. 1057High-resolution faster modified look-locker inversion
recovery (fast-MOLLI) for RV extracellular volume fraction at 3T: A feasibility
study. Eur Heart J Cardiovasc Imaging 2013. [DOI: 10.1093/ehjci/jet070k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Tyler A, DeVier M, Carpenter C, Carr M, Trabue C. Successful treatment of pulmonary blastomycosis in a pregnant woman using itraconazole. Ann Pharmacother 2013; 47:425-6. [PMID: 23482735 DOI: 10.1345/aph.1r679] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Carr M, Ravi V, Reddy GS, Veranna D. Machine Learning Techniques Applied to Profile Mobile Banking Users in India. INTERNATIONAL JOURNAL OF INFORMATION SYSTEMS IN THE SERVICE SECTOR 2013. [DOI: 10.4018/jisss.2013010105] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This paper profiles mobile banking users using machine learning techniques viz. Decision Tree, Logistic Regression, Multilayer Perceptron, and SVM to test a research model with fourteen independent variables and a dependent variable (adoption). A survey was conducted and the results were analysed using these techniques. Using Decision Trees the profile of the mobile banking adopter’s profile was identified. Comparing different machine learning techniques it was found that Decision Trees outperformed the Logistic Regression and Multilayer Perceptron and SVM. Out of all the techniques, Decision Tree is recommended for profiling studies because apart from obtaining high accurate results, it also yields ‘if–then’ classification rules. The classification rules provided here can be used to target potential customers to adopt mobile banking by offering them appropriate incentives.
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Roche SE, Wicks R, Garner MG, East IJ, Paskin R, Moloney BJ, Carr M, Kirkland P. Descriptive overview of the 2011 epidemic of arboviral disease in horses in Australia. Aust Vet J 2012; 91:5-13. [DOI: 10.1111/avj.12018] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/18/2012] [Indexed: 11/28/2022]
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Chattopadhyay D, Mostafa ML, Carr M. Acute neck pain referred to the surgeon: Lemierre's syndrome as a differential diagnosis. Ann R Coll Surg Engl 2012; 94:e132-3. [PMID: 22507711 PMCID: PMC3705259 DOI: 10.1308/003588412x13171221589414] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/05/2011] [Indexed: 11/22/2022] Open
Abstract
Lemierre's syndrome is usually reported in the young and in fit individuals. We report a case of an 81-year-old woman who presented with thrombophlebitis of the internal jugular vein with a pulmonary embolism.
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Kinsella K, Kelly SB, DeGascun CF, Carr M, Duggan M, Hutchinson M, Tubridy N, McGuigan C. 0854 The sensitivity of JC virus DNA detection vs JC virus antibody testing in a natalizumab-treated group of relapsing MS patients. Journal of Neurology, Neurosurgery and Psychiatry 2012. [DOI: 10.1136/jnnp-2011-301993.35] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Fernandes AR, Tlustos C, Rose M, Smith F, Carr M, Panton S. Polychlorinated naphthalenes (PCNs) in Irish foods: Occurrence and human dietary exposure. CHEMOSPHERE 2011; 85:322-328. [PMID: 21783225 DOI: 10.1016/j.chemosphere.2011.06.093] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 05/11/2011] [Accepted: 06/23/2011] [Indexed: 05/31/2023]
Abstract
The concentrations of selected polychlorinated naphthalene (PCN) congeners (PCNs 52, 53, 66/67, 68, 69, 71/72, 73, 74 and 75) were determined in 100 commonly consumed foods, in the first study on occurrence of these contaminants in the Republic of Ireland. Congener selection was based on current knowledge on PCN occurrence and toxicology, and the availability of reliable reference standards. The determinations were carried out using validated analytical methodology based on 13C10 labelled internal standardisation and measurement by HRGC-HRMS. The results showed PCN occurrence in the majority of studied foods--milk, fish, dairy and meat products, eggs, animal fat, shellfish, offal, vegetables, cereal products, etc. ranging from 0.09 ng kg(-1) whole weight for milk to 59.3 ng kg(-1) whole weight for fish, for the sum of the measured PCNs. The most frequently detected congeners were PCNs 66/67, PCN 52, and PCN 73. The highest concentrations were observed in fish, which generally showed congener profiles that reflect some commercial mixtures. The data compares well with other recently reported data for Western Europe. The dioxin-like toxicity (PCN TEQ) associated with these concentrations is lower than that reported for chlorinated dioxins or PCBs in food from Ireland. The dietary exposure of the Irish adult population to PCNs was calculated following a probabilistic approach, using the full dataset of occurrence and current consumption data. The estimates of dietary intakes at approximately 0.14 pg TEQ kg bw(-1) month(-1) for adults on an average diet, reflects the relatively lower occurrence levels.
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Fontaine E, McShane J, Carr M, Shackcloth M, Mediratta N, Page R, Poullis M. Should we operate on microscopic N2 non-small cell lung cancer? Interact Cardiovasc Thorac Surg 2011; 12:956-61; discussion 961. [DOI: 10.1510/icvts.2010.255323] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Carney K, Light D, Carr M. A study of male breast cancer in a district general hospital. Eur J Surg Oncol 2011. [DOI: 10.1016/j.ejso.2011.03.108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Flood C, Ufnar J, Wang S, Johnson J, Carr M, Ellender R. Lack of correlation between enterococcal counts and the presence of human specific fecal markers in Mississippi creek and coastal waters. WATER RESEARCH 2011; 45:872-878. [PMID: 20950837 DOI: 10.1016/j.watres.2010.09.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2010] [Revised: 09/13/2010] [Accepted: 09/17/2010] [Indexed: 05/30/2023]
Abstract
The objective of this study was to determine whether statistically valid correlations could be shown between enterococcal counts of samples from creek and coastal sites and the presence of two molecular, library-independent markers that specify human and/or sewage pollution. Four hundred ninety samples were collected between August 2007 and April 2009 to determine enterococcal counts and the presence of genetic markers for the sewage indicator organisms Methanobrevibacter smithii and Bacteroidales. The presence of human/sewage markers and enterococcal counts were higher in creek samples than coastal samples, but the higher creek levels did not statistically correlate with the either enterococcal count or the presence of the markers present in coastal samples. Furthermore, there was no correlation between enterococcal counts in coastal samples and either marker at any of the beach sites tested. The results of this investigation in Mississippi coastal waters suggest that human/sewage markers are unlikely to correlate with enterococci counts in the nearshore environment and that enterococcal counts may be indicative of other animal or environmental sources. Additionally, a study comparing conventional gel electrophoresis with capillary electrophoresis did not convincingly establish that one method was better than the other in regard to the results obtained. The capillary method does allow reproducibility of results and the ability to analyze multiple samples in a short period of time; however, the operational expenditures exceed the cost of traditional gel electrophoresis.
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White V, Carney K, Hollingsworth A, Tenna AS, McClean N, Carr M, Youssef M. Breast reconstruction for breast cancer patients. An audit of services in a non-screening district general hospital. Int J Surg 2011. [DOI: 10.1016/j.ijsu.2011.07.207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Raghavendra GKG, Sreenivasa RH, Ashok K, Chitsabesan P, McLean NR, Youssef M, Piper M, Carr M. Surgically placed wound catheters (SPWC) and local anaesthetic infusion in breast surgery: efficacy and safety analysis. Breast Dis 2011; 33:1-8. [PMID: 21965305 DOI: 10.3233/bd-2010-0316] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
BACKGROUND The effectiveness of surgically placed wound catheters (SPWC) and local anaesthetic infusion in the management of post-operative pain following breast surgery is controversial. This meta-analysis was performed to assess efficacy SPWC compared to other techniques of pain management. MATERIAL AND METHODS The meta-analysis included randomised control trials that compared SPWC with other forms of pain control. Post-operative opioid requirements and pain measured in visual analogue scale (VAS) were analysed using Comprehensive Meta-analysis Software version 2. Literature was reviewed for the safety of the SPWC and local anaesthetic infusion. RESULTS Four randomised controlled trials evaluating 147 women were included in the final analysis. The overall standard difference in means was 0.094 and 0.033 for post-operative opioid requirement and pain respectively favouring the SPWC and local anaesthetic infusion group. It is a safe technique with no major adverse events as a result. CONCLUSION Surgically placed wound catheters and local anaesthetic infusion is clinically safe in a wide range of surgical procedures on the breast and there appears to be a trend towards improved post operative pain relief. The studies analyzed in this review have several important drawbacks such as inadequate power to detect significant differences (none of them included more than 50 patients). A well designed RCT of patients undergoing breast surgery with an adequate number is of patients required to emphatically demonstrate if the operative site infusion with local anaesthetic solution postoperatively is safe and efficacious compared to opioid based regimens alone for post operative pain relief.
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White V, Harvey JR, Griffith CDM, Youssef M, Carr M. Sentinel lymph node biopsy in early breast cancer surgery--working with the risks of vital blue dye to reap the benefits. Eur J Surg Oncol 2010; 37:101-8. [PMID: 21195576 DOI: 10.1016/j.ejso.2010.12.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2010] [Revised: 11/21/2010] [Accepted: 12/06/2010] [Indexed: 11/24/2022] Open
Abstract
AIMS Sentinel lymph node biopsy (SLNB) is an important method of staging early breast cancer because of the inherent benefits it confers on patients in terms of arm function and quality of life. Its success depends on a high level of accuracy in detecting the sentinel node. This is achieved by a dual mapping technique that employs a radio-labelled nanocolloid and a vital blue dye. The vital dyes however carry the risk of anaphylaxis, and as more surgeons employ SLNB in their daily practice, a proportionate rise in the number of anaphylactic reactions can be expected. A comprehensive review of risks and benefits associated with using vital blues dyes has not been published and therefore a retrospective review was undertaken of the different levels of anaphylaxis associated with vital dyes as well as their benefits in SLNB. METHODS An OVID MEDLINE search was performed of the English published literature using appropriate search terms to find published trial data and case series that focused on adverse reactions to vital blue dyes. RESULTS The risk of severe anaphylaxis (grade 3) can be as low as 0.06%, and up to 0.4% for patients undergoing SLNB when data is analysed from large trials. Furthermore, adverse reactions associated with blue dyes are reversible with appropriate management. CONCLUSIONS Surgeons should continue to use vital dyes to ensure that SLNB remains a highly sensitive procedure.
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Guru Raghavendra GK, White V, Harvey J, Youssef M, Wotherspoon W, Carr M. Efficacy of intra-operative wire localisation of breast lesions using ultrasound. Eur J Surg Oncol 2010. [DOI: 10.1016/j.ejso.2010.08.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Blair JE, Carr M. Distribution of Phage Groups of Staphylococcus aureus in the Years 1927 through 1947. Science 2010; 132:1247-8. [PMID: 17801672 DOI: 10.1126/science.132.3435.1247] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The phage typing patterns of 194 typable strains of Staphylococcus aureus isolated in the years 1927 through 1947 and preserved as stock cultures revealed that 43 strains were of phage type 80/81. The occurrence of other typable strains in the broad phage groups I, II, and III corresponded closely to the frequency distribution of staphylococci reported in 1945 by Wilson and Atkinson.
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Carr M. The Small- and Medium-sized Enterprises Office (SME Office) at the European Medicines Agency. Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz 2009; 53:20-3. [DOI: 10.1007/s00103-009-0989-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Raghavendra GKG, White V, Harvey JR, Youssef M, Wotherspoon W, Carr M. Efficacy of intra-operative wire localisation of breast lesions using ultrasound. Breast Cancer Res 2009. [PMCID: PMC4284862 DOI: 10.1186/bcr2401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
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Fernandes A, Tlustos C, Smith F, Carr M, Petch R, Rose M. Polybrominated diphenylethers (PBDEs) and brominated dioxins (PBDD/Fs) in Irish food of animal origin. FOOD ADDITIVES & CONTAMINANTS PART B-SURVEILLANCE 2009; 2:86-94. [DOI: 10.1080/02652030903042525] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Thompson JG, Vanderwerf S, Seningen J, Carr M, Kloss J, Apple FS. Free Oxycodone Concentrations in 67 Postmortem Cases from the Hennepin County Medical Examiner's Office. J Anal Toxicol 2008; 32:673-9. [DOI: 10.1093/jat/32.8.673] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Radford S, Carr M, Hehir M, Davis B, Robertson L, Cockshott Z, Tipler S, Hewlett S. 'It's quite hard to grasp the enormity of it': perceived needs of people upon diagnosis of rheumatoid arthritis. Musculoskeletal Care 2008; 6:155-167. [PMID: 18649347 DOI: 10.1002/msc.132] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
OBJECTIVES The diagnosis of rheumatoid arthritis (RA) brings rapid pharmacological and multidisciplinary team interventions to address inflammatory processes and symptom management. However, people may also need support on the journey to self-management. The aim of this study was to explore what professional support patients feel they receive upon diagnosis, and what support they feel would be most helpful. METHODS Two focus groups comprised patients with at least five years'; disease duration (n = 7), and patients more recently diagnosed (5-18 months, n = 5). The latter had attended at least two appointments in a rheumatology nurse specialist clinic during the previous year, aimed at providing support upon diagnosis. Transcripts were subjected to thematic analysis to identify common issues regarding support needs, which were then grouped into themes. Interviewing and analysis was performed by researchers not involved in clinical care. RESULTS Four overarching themes emerged. 'Information' was needed about the symptoms of RA, its management and personal outcome, while 'Support' related to emotional needs ('It's quite hard to grasp the enormity of it'). Information and Support overlapped, in that patients wanted someone to talk to, and to be listened to. These two themes were underpinned by issues of service delivery: 'Choice' (patient or professional to talk to, groups, one-to-one) and 'Involvement' (holistic care, partnership), which overlapped in terms of the opportunity to decide when and which interventions to access. CONCLUSIONS People with RA report not only informational, but also emotional support needs at diagnosis. The potential for delivering emotional support to patients around the time of diagnosis warrants further exploration.
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Hehir M, Carr M, Davis B, Radford S, Robertson L, Tipler S, Hewlett S. Nursing support at the onset of rheumatoid arthritis: Time and space for emotions, practicalities and self-management. Musculoskeletal Care 2008; 6:124-134. [PMID: 17922490 DOI: 10.1002/msc.115] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
BACKGROUND Following a diagnosis of rheumatoid arthritis (RA), patients have to adapt to lifelong, unpredictable but repeated episodes of pain and disability, potentially leading to permanent loss of function and its consequences on their lives. We established nurse clinics with the aim of supporting newly diagnosed RA patients in adapting to and managing their long-term condition. The aim of this study was to explore the content of clinic discussions in this new clinical service, in order to ascertain patients' needs upon diagnosis. METHODS All clinic letters from the nurse to the family doctor were analysed. Every topic mentioned was systematically coded independently by a researcher and a patient research partner, who compared and agreed codes. Codes were organized into categories, and, finally, into overarching themes. RESULTS Twenty-four patients had 74 appointment letters. A total of 79 codes were identified, from which ten categories emerged, and, finally, three overarching themes. The first theme related to 'Emotional support', which underpinned the other two themes and was discussed in almost all appointments. Issues included discussions about the emotional consequences of RA, needing time to adjust, frustration and fears for the future. The second theme 'Practicalities of the treatment of RA', included subordinate themes relating to the nature of RA, such as identity, cause, timeline, consequences and treatment. Medication issues were discussed and referrals to the multidisciplinary team were made. The final theme related to the 'Self-management of RA', and included discussions on physical symptoms and their management. CONCLUSIONS The offer to attend a nurse clinic soon after diagnosis allowed RA patients to discuss a wide range of practical and self-management issues. However, most patients also took the opportunity and time to discuss emotional reactions and adaptations to diagnosis. The data suggest an unmet need for emotional support that a nurse clinic might be able to provide.
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Irwin D, Helm K, Campbell N, Imamura M, Fagan K, Harral J, Carr M, Young KA, Klemm D, Gebb S, Dempsey EC, West J, Majka S. Neonatal lung side population cells demonstrate endothelial potential and are altered in response to hyperoxia-induced lung simplification. Am J Physiol Lung Cell Mol Physiol 2007; 293:L941-51. [PMID: 17693487 DOI: 10.1152/ajplung.00054.2007] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Lung side population (SP) cells are resident lung precursor cells with both epithelial and mesenchymal potential that are believed to play a role in normal lung development and repair. Neonatal hyperoxic exposure impairs lung development leading to a long-term decrease in gas exchange surfaces. The hypothesis that lung SP cells are altered during impaired lung development has not been studied. To address this issue, we characterized the endothelial potential of neonatal lung SP and subsets of lung SP from neonatal mice following hyperoxic exposure during room air recovery. Lung SP cells were isolated and sorted on the basis of their capacity to efflux Hoechst 33342. The lung SP was further sorted based on expression of Flk-1 and CD45. In vitro, both CD45pos/Flk-1pos and CD45neg/Flk-1pos bind isolectin B4 and incorporate LDL and form networks in matrigel, indicating that these populations have endothelial cell characteristics. Hyperoxic exposure of neonatal mice resulted in subtle changes in vascular and alveolar density on P13, which persisted with room air recovery to P41. During room air recovery, a decrease in lung SP cells was detected in the hyperoxic-exposed group on postnatal day 13 followed by an increase on day 41. Within this group, the lung SP subpopulation of cells expressing CD45 increased on day 21, 41, and 55. Here, we show that lung SP cells demonstrate endothelial potential and that the population distribution changes in number as well as composition following hyperoxic exposure. The hyperoxia-induced changes in lung SP cells may limit their ability to effectively contribute to tissue morphogenesis during room air recovery.
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