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Ghebrehewet S, Falconer M, McDonald P, Schlecht B. MMR vaccine uptake rates: a data validation study. COMMUNICABLE DISEASE AND PUBLIC HEALTH 2003; 6:144-6. [PMID: 12889295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
As part of our investigation into the decrease in the measles, mumps and rubella (MMR) vaccine uptake rates, we validated MMR vaccination records of all children born between 01/09/1998 and 31/08/1999 in our area (North Cheshire, South Cheshire, and Wirral). A significant number of children had received their MMR vaccine but were not recorded as such by the Child Health Computer System (CHCS). Reported COVER (cover of vaccination evaluated rapidly) data uptake (combined) for North Cheshire, South Cheshire, and Wirral Health Authorities for the period covered by the data validation study was 90.5%, the corrected uptake following the validation was 92.6%, 2.1% higher than the reported coverage. If the coverage data were to continue to form part of the NHS indicators of PCT performance, action by all PCTs to improve accuracy of immunisation data would be highly desirable. Electronic transfer of information from practices to the CHCS and between CHCSs, i.e. across boundaries, could improve data accuracy.
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Rossney AS, McDonald P, Humphreys H, Glynn GM, Keane CT. Antimicrobial resistance and epidemiological typing of methicillin-resistant Staphylococcus aureus in Ireland (North and South), 1999. Eur J Clin Microbiol Infect Dis 2003; 22:379-81. [PMID: 12750958 DOI: 10.1007/s10096-003-0917-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Burd M, Humphreys H, Glynn G, Mitchell E, McDonald P, Johnson H, McDonnell B, Doyle D, Rossney A. Control and the prevention of methicillin-resistant Staphylococcus aureus in hospitals in Ireland: North/South Study of MRSA in Ireland 1999. J Hosp Infect 2003; 53:297-303. [PMID: 12660127 DOI: 10.1053/jhin.2002.1393] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
As part of an all-island survey of methicillin-resistant Staphylococcus aureus (MRSA) in the Republic of Ireland (the South), where there is a mixed public and private healthcare system, and Northern Ireland (the North), where the healthcare system is part of the UK National Health Service, a questionnaire was circulated to all participating hospitals on measures routinely taken to control MRSA. Response rates were 100% in the North and 89% in the South. Over 70% of hospitals screened particular groups of patients on admission to hospital. Ninety-five percent of hospitals in the North and 88% in the South attempted to eradicate MRSA from carriage sites. Most hospitals attempted to isolate or cohort positive patients. About a quarter of hospitals in both parts of Ireland screened new healthcare workers for the presence of MRSA. Terminal decontamination of the environment after the discharge of a patient positive for MRSA was the norm in over 90% of hospitals, however, 6% of hospitals in the South used inappropriate disinfectants for MRSA. All hospitals in the North, but a minority (41%) in the South, had written antibiotic prescribing policies, but only 65% of hospitals in the South had access to an infection control committee, acute hospitals having greater access than district hospitals. The prevention and control of spread of MRSA remains a major challenge in the North and in the South. Although most hospitals in the North and in the South implemented current recommended guidelines on the control of MRSA in hospitals, there was some variability that may be resource related. Policies need to be reviewed in the light of the changing epidemiology of MRSA.
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McDonald P, Lewis M, Murphy B, O'Reilly R, Singh SM. Appraisal of genetic and epigenetic congruity of a monozygotic twin pair discordant for schizophrenia. J Med Genet 2003; 40:E16. [PMID: 12566534 PMCID: PMC1735364 DOI: 10.1136/jmg.40.2.e16] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Smith CN, Goshawk JA, Charles K, McDonald P, Leonard KS, McCubbin D. MEAD (part II)-Predictions of radioactivity concentrations in the Irish Sea. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2003; 68:193-214. [PMID: 12782473 DOI: 10.1016/s0265-931x(03)00041-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The predictions from MEAD, a model that simulates the transport of radionuclides in the marine environment, are presented for the Irish Sea. MEAD predictions for (137)Cs and Pu(alpha) are presented following discharges from BNFL Sellafield and the predictions compared to measured data from near the discharge location and further a field in the Irish Sea. The model performs well in most circumstances given the uncertainties involved in both modelling and data collection although some inconsistencies in the predictions are found. MEAD is also compared to other models of radionuclide transport in the Irish Sea.
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Tansley P, Birks E, McDonald P, Hipkin M, Hardy J, Bowles C, Banner N, Khaghani A, Yacoub M. Serious abdominal complications of intra-peritoneal placement of left ventricular assist devices. J Heart Lung Transplant 2003. [DOI: 10.1016/s1053-2498(02)01089-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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82
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Goshawk JA, Clarke S, Smith CN, McDonald P. MEAD (part I)--a mathematical model of the long-term dispersion of radioactivity in shelf sea environments. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2003; 68:115-135. [PMID: 12763324 DOI: 10.1016/s0265-931x(03)00040-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A mathematical model (MEAD) that simulates the transport of radioactivity in shelf-sea environments is presented. In the model it is assumed that the radioactivity can be present in three phases and transport both within and between the phases is captured. The set-up of the model for the Irish Sea is described and results from a simple discharge scenario are presented for (137)Cs and (239)Pu. From these results it appears that MEAD provides a good representation of the transport of radionuclides in the Irish Sea.
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Kinateder K, McDonald P. An Ito formula for domain-valued processes driven by stochastic flows. Probab Theory Relat Fields 2002. [DOI: 10.1007/s004400200201] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Humphreys H, Glynn G, Rossney A, McDonald P, Johnson H, McDonnell R, Doyle D, Mitchell E, Burd M. Methicillin-resistant Staphylococcus aureus: laboratory detection methods in use in the Republic of Ireland and Northern Ireland. Br J Biomed Sci 2002; 59:7-10. [PMID: 12000191 DOI: 10.1080/09674845.2002.11783626] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
There is no universally agreed laboratory protocol for the detection of methicillin-resistant Staphylococcus aureus (MRSA) and hence a variety of approaches are used. As part of an all-island survey of MRSA in the Republic of Ireland (the South) and Northern Ireland (the North), a questionnaire was circulated to 14 participating laboratories in the North and 49 in the South, to determine the methods used to isolate MRSA from clinical specimens, identify S. aureus and test for susceptibility to methicillin. Almost two-thirds (64%) of laboratories in the North but only 16% of laboratories in the South use enrichment culture. There is heavy reliance on commercial kits to confirm the identification of S. aureus in the South but all laboratories in the North use the staphylocoagulase test. More than 90% of all laboratories use a disc method for susceptibility testing and 71% of laboratories in the North supplement this with the E-test; however, a range of methicillin disk concentrations are in use. There is a need to review current laboratory methods used to detect MRSA, with follow-up audit on their implementation. Additional resources may be needed in some laboratories to comply with revised guidelines, and reference facilities are required to assess new commercially available techniques and to confirm the identification of unusual or difficult strains.
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Hoontrakoon R, Chu HW, Gardai SJ, Wenzel SE, McDonald P, Fadok VA, Henson PM, Bratton DL. Interleukin-15 inhibits spontaneous apoptosis in human eosinophils via autocrine production of granulocyte macrophage-colony stimulating factor and nuclear factor-kappaB activation. Am J Respir Cell Mol Biol 2002; 26:404-12. [PMID: 11919076 DOI: 10.1165/ajrcmb.26.4.4517] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Prolonged eosinophil survival, i.e., reduced apoptosis, is implicated in the pathogenesis of chronic allergic inflammation. Here we demonstrate that interleukin (IL)-15, in the presence or absence of tumor necrosis factor (TNF)-alpha, reduces spontaneous apoptosis in freshly isolated human eosinophils. The prosurvival effect of IL-15 was abrogated by neutralizing antibody to granulocyte macrophage-colony stimulating factor (GM-CSF), although GM-CSF was not detected in conditioned media by ELISA. Additionally, the effect of IL-15 on spontaneous eosinophil apoptosis appeared to require nuclear factor-kappaB (NF-kappaB) activation based on evidence for NF-kappaB nuclear translocation and abrogation of the effect by the NF-kappaB inhibitor, Bay 11- 7082. Finally, the data demonstrate that IL-15 expression is higher in the submucosa of endobronchial tissues from subjects with moderate to severe asthma when compared with control subjects. Thus, our results suggest that IL-15, either alone or in combination with TNF-alpha, may perpetuate allergic inflammation by reduction of spontaneous eosinophil apoptosis through autocrine production of GM-CSF and NF-kappaB activation.
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McDonald P. McDonald's quotations. J R Soc Med 2002. [DOI: 10.1258/jrsm.95.3.166-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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87
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Pal BR, Singh P, McDonald P, Dogra N, Karnik N, Essex C, Barbour JVR, Bhopal R. Racism in medicine. West J Med 2001. [DOI: 10.1136/bmj.323.7321.1125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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88
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McDonald P. Racism in medicine. Institutional racism in the BMJ. BMJ (CLINICAL RESEARCH ED.) 2001; 323:1125-6; author reply 1127. [PMID: 11725747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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Battersby M, McDonald P, Pearce R, Tolchard B, Allen K. The changing attitudes of health professionals and consumers towards a coordinated care trial--SA HealthPlus. AUST HEALTH REV 2001; 24:172-8. [PMID: 11496460 DOI: 10.1071/ah010172a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The national coordinated care trials have been a vehicle for health reform in Australia, driven by escalating health care costs and projections of an ageing population. The first round of trials conducted between 1997 and 1999 set the trials a challenge to reduce financial and system barriers to enable health professionals in all sectors and consumers to develop service delivery models which would give better outcomes for patients within existing resources. As part of a change management strategy, the developers of the SA HealthPlus trial assessed the attitudes of health professionals and consumers involved in designing the projects which made up the larger trial, prior to trial development and twelve months later. This paper reports on the results of the survey and how initial enthusiasm gave way to appropriate anxiety as the complexities of creating a new system of care from reactive to prospective patient centred care planning, became a reality. The survey enabled trial developers to show evidence of acceptability for the new model of care and identify areas of concern and appropriate strategies for the project teams. This type of survey and the issues identified may be of benefit to the second round coordinated care trials and health regions aiming to initiate coordinated care programs.
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McDonald P. Too many and too few: population dilemmas of the 21st century. JOURNAL OF HEALTH, POPULATION, AND NUTRITION 2001; 19:155-157. [PMID: 11761767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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91
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McDonald P. Remarks on the context of Helmholtz's "Ueber das Wesen der Fäulniss und Gährung". SCIENCE IN CONTEXT 2001; 14:493-504. [PMID: 12068898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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McDonald P, Herity B, Johnson Z, O'Kelly F. Views of Irish general practitioners on screening for cervical cancer. Ir J Med Sci 2001; 170:186-8. [PMID: 12120972 DOI: 10.1007/bf03173887] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND A national cervical screening programme is being established in Ireland and there is little information on the level of resources required. AIMS To obtain information on attitudes of Irish general practitioners (GPs) and on the resources needed by them in relation to participation in the programme. METHODS An anonymous postal questionnaire was sent to a random sample of 600 GPs, approximately 25% of the total population of GPs in Ireland. RESULTS A response rate of 87.5% was obtained. The majority (88%) would participate in a national programme. Those who would not were more likely to be in single-handed practice, aged over 44 years, have no ancillary staff, no computer and be in rural practice. GPs were in favour of a special fee for smear taking, a training programme and management guidelines on the test report. They did not want bonus payments for achieving targets or the report to be sent to the client as well as the doctor. CONCLUSION GPs will support a national cervical screening programme but a number of organisational issues must be discussed with them to ensure a successful programme.
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Watts SA, Daly B, Anthony M, McDonald P, Khoury A, Dahar W. The effect of age, gender, risk level and glycosylated hemoglobin in predicting foot amputation in HMO patients with diabetes. JOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS 2001; 13:230-5. [PMID: 11930474 DOI: 10.1111/j.1745-7599.2001.tb00026.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE To determine if age, gender, risk level and glucosylated hemoglobin could predict foot amputations in HMO patients with diabetes. DATA SOURCES A retrospective chart review of a non-random sample of 27 patients with amputation and 110 randomly selected patients without amputation during the same time period. Chi-square, t-tests and logistic regression were used to analyze the data. CONCLUSIONS There was no significant difference between the group with amputation and those without amputation in age or gender. However, there was a significant difference between the two groups in the risk stratification (p = .005) and glycosylated hemoglobin levels (p = .058). IMPLICATIONS FOR PRACTICE Nurse practitioners can effectively screen for amputation risk factors and closely monitor glycosylated hemoglobin levels of diabetic patients to reduce the incidence of vascular complications and related lower extremity amputation.
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Read KM, Currie B, McDonald P, Gordon DL. Reactivation of latent melioidosis in association with staphylococcal endocarditis. Intern Med J 2001. [DOI: 10.1111/j.1444-0903.2001.00022.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Read KM, Currie B, McDonald P, Gordon DL. Reactivation of latent melioidosis in association with staphylococcal endocarditis. Intern Med J 2001; 31:130-1. [PMID: 11480478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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McDonald P, Vives i Batlle J, Bousher A, Whittall A, Chambers N. The availability of plutonium and americium in Irish Sea sediments for re-dissolution. THE SCIENCE OF THE TOTAL ENVIRONMENT 2001; 267:109-123. [PMID: 11286207 DOI: 10.1016/s0048-9697(00)00771-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The availability of plutonium and americium, for re-dissolution from offshore sediments into Irish Sea water, has been examined. Sediments collected from the mud-patch near the Cumbrian coast were characterized in terms of spatial location, particle size, partitioning of radionuclides with respect to physico-chemical bonds and availability of actinides for release into seawater. Sequential extraction investigations revealed that plutonium was predominantly associated with strongly bound sesquioxide and organic complex fractions. Americium was associated mainly with the organic complex fraction, but a significant fraction was in carbonate form. Sediment/water re-dissolution experiments with and without stirring were compared to simulate the effect of disturbing bed sediment. After 1 week, neither set of re-dissolution data provided significant trends between dissolved activity and time. Stirred systems appeared to release 2.5 times more plutonium and americium into seawater than unstirred systems. Measured 239,240Pu and 241Am distribution coefficients (Kd values) were both typically approximately 10(5) l kg(-1). 241Am Kd values are an order of magnitude lower than previously reported for the north-eastern Irish Sea, but similar to western Irish Sea values. Overall, the fractions of plutonium and americium available for re-dissolution from bed sediment are very low at < 0.1%, with proportionally more plutonium being released than americium. These findings lend further support for the extrapolation of laboratory-derived information to environmental conditions.
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Whittall AJ, McDonald P, Jackson D, Tossell PJ. Alpha-emitting 'hot particles' in the vicinity of BNFL Sellafield, Cumbria. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2000; 20:433-442. [PMID: 11140714 DOI: 10.1088/0952-4746/20/4/306] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In a survey of environmental samples in the vicinity of BNFL Sellafield, two alpha-emitting radioactive particles were found in samples of grass. One particle appears to be of mineral origin, the other was not definitively identified, but may be a fragment of fuel cladding. Conservative estimates of the activities of these particles are very low. The abundance of radioactive particles in the terrestrial food chain appears to be low, with no evidence for any alpha-emitting hot particles in foodstuffs for consumption by humans. Results suggest that there is no significant dose to man through inhalation or ingestion pathways.
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McDonald P. Out of harm's way. THE HEALTH SERVICE JOURNAL 2000; 110:30. [PMID: 11184507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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99
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Smith CN, Clarke S, McDonald P, Goshawk JA, Jones SR. Reconstructing historical radionuclide concentrations along the east coast of Ireland using a compartmental model. THE SCIENCE OF THE TOTAL ENVIRONMENT 2000; 254:17-30. [PMID: 10845444 DOI: 10.1016/s0048-9697(00)00430-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
A mathematical model is presented that simulates the annually averaged transport of radionuclides, originating from the BNFL reprocessing plant at Sellafield, throughout the Irish Sea. The model, CUMBRIA77, represents the processes of radionuclide transport and dispersion in the marine environment and allows predictions of radionuclide concentration in various environmental media, including biota, to be made throughout the whole of the Irish Sea. In this paper we describe the use of the model to reconstruct the historical activity concentrations of 137Cs and 239+240Pu in a variety of environmental media in the western Irish Sea and along the Irish east coast back to 1950. This reconstruction exercise is of interest because only limited measurements of 137Cs and 239+240Pu activity are available prior to the 1980s. The predictions were compared to the available measured data to validate their accuracy. The results of the reconstruction indicate that activity concentrations of 137Cs in the western Irish Sea follow a similar, though slightly delayed and smoothed, profile to the discharges from the Sellafield site, with concentrations at the time of peak discharge (the mid-1970s) being around an order of magnitude higher than those measured in the 1980s and 1990s. By contrast, the concentrations of 239+240Pu at the time of peak discharges were similar to those presently measured. These differences reflect the distinct marine chemistries of the two nuclides, in particular the higher propensity of plutonium to bind to sediments leading to extended transport times. Despite these differences in behaviour the doses to Irish seafood consumers from 137Cs remain significantly higher than those from 239+240Pu.
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Skarsgard PL, Wang X, McDonald P, Lui AH, Lam EK, McManus BM, van Breemen C, Laher I. Profound inhibition of myogenic tone in rat cardiac allografts is due to eNOS- and iNOS-based nitric oxide and an intrinsic defect in vascular smooth muscle contraction. Circulation 2000; 101:1303-10. [PMID: 10725291 DOI: 10.1161/01.cir.101.11.1303] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The physiological consequences of inducible NO synthase (iNOS) expression were studied in allograft coronary arteries by pressure myography. METHODS AND RESULTS Septal coronary arteries (diameter, 200.6+/-3.3 microm) were harvested from allograft and isograft hearts, and their myogenic properties were measured before and after iNOS and nonselective NOS inhibition with aminoguanidine (AG, 100 micromol/L) and N(G)-nitro-L-arginine methyl ester (L-NAME) (200 micromol/L). Fura 2 fluorescence microscopy was used to measure [Ca(2+)](i) in isolated endothelial cells. Monoclonal anti-iNOS immunostains demonstrated iNOS protein in day 2, 7, 14, and 28 allograft vessels, but only in day 2 isograft vessels. Myogenic tone was profoundly inhibited in allograft vessels from day 4 onward. In day 4 allograft vessels, these differences were abolished by L-NAME but not AG, suggesting greater basal release of eNOS-based NO from allograft endothelium. Fluorescence measurements confirmed elevation of [Ca(2+)](i) in day 4 allograft endothelium, providing a mechanism for enhanced eNOS activity. For days 7 to 28, AG potentiated myogenic tone in allograft but not isograft vessels, indicating that vasoactive iNOS-based NO was present. In mature vessels, constriction via agonist- and depolarization-mediated mechanisms showed parallel inhibition, suggesting an intrinsic defect in vascular smooth muscle cell contraction. CONCLUSIONS Our data indicate that the profound inhibition of myogenic tone in allograft arteries involves direct vasodilation by eNOS- and iNOS-based NO, as well as an intrinsic defect in vascular smooth muscle contraction. The hemodynamic profile resulting from these changes in allograft resistance vessel function would favor movement of extracellular fluid from the intravascular space into the myocardial interstitium, resulting in edema, increased ventricular stiffness, and poor ventricular performance.
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