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U Kirkpatrick

Publications and source records attributed to U Kirkpatrick.

4 recordsLinked to original sources
PubMed2001

Changes in endothelial, leucocyte and platelet markers following contrast medium injection during angiography in patients with peripheral artery disease.

Peripheral artery angiography, a common diagnostic procedure, may cause early and late adverse reactions, such as anaphylaxis, thrombosis and possible progression of the underlying arterial disease. To test the hypothesis that radiographic contrast medium may contribute to these events by adversely affecting the endothelium, leucocytes and/or platelets, 19 subjects undergoing angiography for the investigation and/or treatment of lower limb atherosclerosis were recruited. Blood was obtained from the external iliac vein before, and at serial intervals after, the injection of radiographic contrast medium into the ipsilateral femoral artery for diagnostic use. Markers of endothelial cell injury (von Willebrand factor (vWf)), platelet activation (soluble P-selectin) and leucocyte activation (neutrophil elastase and soluble L-selectin) were measured in citrated plasma. Soluble intercellular adhesion molecule-1 (sICAM-1) and thromboxane B(2), which are non-specific markers of inflammation, were also measured. Compared with the sample prior to angiography, levels of soluble L-selectin and sICAM-1 were reduced (p<0.02) immediately after passage of the last bolus of contrast medium. 15 min later, levels returned to normal but the level of vWf had increased (p<0.02). After 30 min, only levels of thromboxane B(2) were increased (p<0.05). The following day both vWf (p<0.01) and soluble P-selectin (p<0.05) were increased. These data point to both early and late effects of contrast medium on markers of endothelial, platelet and leucocyte function.

Aged↗
PubMed1998

The influence of acute smoking on leucocytes, platelets and the endothelium.

Cigarette smoking is a risk factor for the development of atherosclerosis. Possible mechanisms for this include leucocytes and platelet activation, and/or damage to the endothelium, any of which may contribute to changes in thrombosis and haemostasis. We examined the acute effects of smoking on these systems by obtaining blood before, immediately after, and at 10 and 30 min after the rapid smoking of two cigarettes in sequence by 20 smokers. Blood samples taken at the same time points from ten non-smokers acted as control material. In the smokers there was a transient rise in leucocyte count and neutrophil activation, but von Willebrand factor (VWF--marking endothelial damage) increased steadily at each time point (P <0.05). There were no changes in neutrophil elastase, soluble intercellular adhesion molecule-1 (sICAM-1 normally increased in smokers), fibrinogen, platelet count or soluble P-selectin (marking platelet activation, also normally increased in smokers). We conclude that the acute smoking of two cigarettes in succession will activate leucocytes and cause endothelial cell damage, but will not immediately influence platelet activity.

Adult↗
PubMed1997

A UK-wide trial of the Banff classification of renal transplant pathology in routine diagnostic practice.

BACKGROUND: The Banff classification of renal transplant pathology has gained wide support since its introduction in 1993. There have been several studies which have tested its usefulness in the context of research-oriented centres. We sought to evaluate its use in a wider context. METHODS: We recruited pathologists from all but one of the renal transplant centres in the UK. Sections were circulated from 21 selected, 'difficult' cases, in all of which the clinical question was confirmation or exclusion of acute rejection, and in all of which a definite diagnosis had been obvious from the subsequent clinical course. Participants were asked first to diagnose or exclude acute rejection by their usual approach, then to apply the Banff classification. No clinical information was given beyond the time since engraftment, in order to confine the evaluation to the morphological features present in the sections. At the end of the study the subjective impressions of the participants were sought using a structured questionnaire. RESULTS: Using the Banff classification produced no detectable difference in the number of 'correct' diagnoses when compared with a conventional approach, irrespective of whether the 'correct' diagnosis is based on retrospective clinical information or on the consensus opinion of the pathologists involved, and irrespective of where in the Banff schema one applies a 'cut-off' for the diagnosis of acute rejection. However, the reproducibility of the diagnoses was improved. The results suggest that in the Banff classification the best 'cut-off' for the diagnosis of acute rejection is between Banff category 3 and category 4, although in this difficult area we found a large improvement in diagnostic accuracy if input of clinical information occurs. CONCLUSIONS: The improved reproducibility justifies the use of the Banff classification to harmonise approaches between centres, especially in research projects. While there are good reasons also to adopt it in routine diagnostic practice, further refinement is necessary before an improvement in the accuracy of diagnosis can be demonstrated.

Diagnostic Errors↗