Four decades of chronic haemodialysis: lessons from the past and implications for the future.

BACKGROUND: There have been substantial changes in the provision of chronic haemodialysis (HD) therapy over time, yet data regarding the impact of these differences on clinical outcomes are limited. AIM: To identify factors which have significantly changed over the last 40 years in relation to patients receiving maintenance HD therapy. METHODS: All 2,647 patients who were established on the chronic HD programme in Northern Ireland between 1970 and 2010 were included. Clinical data and survival outcomes were obtained from a prospectively recorded database. The study period was divided into four decades in order to assess the temporal changes. RESULTS: The total number of patients receiving HD therapy has risen, and the mean age of the HD population has increased significantly (39.0 years in the 1970s vs. 66.8 years in the 2000s, p < 0.001). Diabetic nephropathy has emerged as the commonest aetiology for ESRD (0% in the 1970s to 20.3% in the 2000s, p < 0.001). The median survival of patients on HD has improved significantly over time from 5.2 months (95% CI 2.6-15.5) in the 1970s to 41.7 months (95% CI 38-45.2) in the 2000s (p < 0.0001). Factors that remained significant in determining survival were age, primary renal diagnosis, and decade of commencement of dialysis. CONCLUSIONS: Survival on HD has significantly improved despite older patients with multiple co-morbidities being accepted for treatment reflecting both increased dialysis frequency and better management of cardiovascular risk factors. The increasing age of HD patients and their improved survival have implications for future planning and delivery of dialysis.

Minimising twins in in vitro fertilisation: a modelling study assessing the costs, consequences and cost-utility of elective single versus double embryo transfer over a 20-year time horizon.

OBJECTIVES: To assess the cumulative costs and consequences of double embryo transfer (DET) or elective single embryo transfer (eSET) in women commencing in vitro fertilisation (IVF) treatment aged 32, 36 and 39 years. DESIGN: Microsimulation model. SETTING: Three assisted reproduction centres in Scotland. SAMPLE: A total of 6153 women undergoing treatment at one of three Scottish IVF clinics, between January 1997 and June 2007. METHODS: A microsimulation model, populated using data inputs derived from a large clinical data set and published literature, was developed to compare the costs and consequences of using eSET or DET over multiple treatment cycles. MAIN OUTCOME MEASURES: Disability-free live births; twin pregnancy rate; women's quality-adjusted life-years (QALYs); health service costs. RESULTS: Not only did DET produce a higher cumulative live birth rate compared with eSET for women of all three ages, but also a higher twin pregnancy rate. Compared with eSET, DET ranged from costing an additional £ 27,356 per extra live birth in women commencing treatment aged 32 years, to costing £ 15,539 per extra live birth in 39-year-old women. DET cost ∼ £ 28,300 and ∼ £ 20,300 per additional QALY in women commencing treatment aged 32 and 39 years, respectively. CONCLUSIONS: Considering the high twin pregnancy rate associated with DET, coupled with uncertainty surrounding QALY gains, eSET is likely to be the preferred option for most women aged ≤ 36 years. The cost-effectiveness of DET improves with age, and may be considered cost-effective in some groups of older women. The decision may best be considered on a case-by-case basis for women aged 37-39 years.

The isolated chicken eye test as a suitable in vitro method for determining the eye irritation potential of household cleaning products.

Eye irritation is an important endpoint in the safety evaluation of consumer products and their ingredients. Several in vitro methods have been developed and are used by different industry sectors to assess eye irritation. One such in vitro method in use for some time already is the isolated chicken eye test (ICE). This investigation focuses on assessing the ICE as a method to determine the eye irritation potential of household cleaning products, both for product safety assurance prior to marketing and for classification and labeling decisions. The ICE involves a single application of test substances onto the cornea of isolated chicken eyes. Endpoints are corneal swelling, corneal opacity and fluorescein retention. The ICE results were compared to historic LVET data in this study due to availability of such in vivo data and the ability to correlate LVET to human experience data on the outcome of accidental exposures to household cleaning products in general. The results of this study indicate that the ICE test is a useful in vitro method for evaluating the eye irritation/corrosion potential and establishing classification and labeling for household cleaning products. For new product formulations, it is best used as part of a weight-of-evidence approach and benchmarked against data from comparable formulations with known eye irritation/corrosion profiles and market experience.

Development of a defined approach for eye irritation or serious eye damage for liquids, neat and in dilution, based on cosmetics Europe analysis of in vitro STE and BCOP test methods.

The focus of Cosmetics Europe's programme on serious eye damage/eye irritation is on development of testing strategies and defined approaches for identification of ocular effects of chemicals in the context of OECD's Guidance Document on an Integrated Approach on Testing and Assessment (IATA) for Serious Eye Damage and Eye Irritation. Cosmetics Europe created a comprehensive database of chemicals for which in vitro data are available with corresponding historical in vivo Draize eye data. This database allowed further exploration of the initially proposed strategies from the CON4EI project and to identify opportunities for refinement. The current analysis focused on the development of a defined approach, applicable to liquid non-surfactant chemicals, neat and in dilution, that can distinguish between the three UN GHS categories (Cat. 1, Cat. 2, and No Cat.). Combining the modified-protocol Short Time Exposure (STE) test method (OECD TG 491 with extension to highly volatile substances) with the Bovine Corneal Opacity and Permeability Laser Light-Based Opacitometer (BCOP LLBO) test method in a Bottom-Up approach identified 81.2% Cat. 1, 56.3% Cat. 2, and 85.3% No. Cat correctly, with an NPV of 96.7% and a PPV of 68.6%. Therefore, the performance of the defined approach was better than the standalone test methods.

Development of a defined approach for eye irritation or serious eye damage for neat liquids based on cosmetics Europe analysis of in vitro RhCE and BCOP test methods.

The focus of Cosmetics Europe's ocular toxicity programme is on development of testing strategies and defined approaches for identification of ocular effects of chemicals in the context of OECD's Guidance Document on an Integrated Approach on Testing and Assessment (IATA) for Serious Eye Damage and Eye Irritation. Cosmetics Europe created a comprehensive database of chemicals for which in vitro data are available with corresponding historical in vivo Draize eye data and physicochemical properties. This database allowed further exploration of the initially proposed strategies from the CON4EI project and to identify opportunities for refinement. One key outcome of this project is that combining in vitro test methods (RhCE and BCOP LLBO) with physicochemical properties in a two-step Bottom-Up approach applicable to neat liquids, resulted in an improvement of the specificity, without reducing the sensitivity, when compared to the combination of in vitro methods alone. The Bottom-Up approach proposed here for neat liquids correctly predicted 58.3% (EpiOcular™ EIT followed by BCOP LLBO) to 62.6% (SkinEthic™ HCE EIT followed by BCOP LLBO) of No Cat., 59.1% to 68.7% of Cat. 2, and 76.5% of Cat. 1. Incorporating specific physicochemical properties with this Bottom-Up approach increased the correct identification of No Cat. neat liquids to between 72.7% and 79.7%.

Topology of the CD2-CD48 cell-adhesion molecule complex: implications for antigen recognition by T cells.

BACKGROUND: The T-lymphocyte cell-surface molecule, CD2, was the first heterophilic cell-adhesion molecule to be discovered and has become an important paradigm for understanding the structural basis of cell adhesion. Interaction of CD2 with its ligands. CD58 (in humans) and CD48 (in mice and rats), contributes to antigen recognition by T cells. CD2, CD48 and CD58 are closely related members of the immunoglobulin superfamily and their extracellular regions are predicted to have very similar structures. The three-dimensional crystal structure of this region of CD2 has been determined, revealing two immunoglobulin domains with the ligand-binding site situated on an exposed beta sheet in the membrane-distal domain. This GFCC'C" beta sheet is also involved in a homophilic 'head-to-head' interaction in the CD2 crystal lattice, which has been proposed to be a model for the interactions of CD2 with its ligands. RESULTS: We show that the CD2-binding site on rat CD48 lies on the equivalent beta-sheet of its membrane-distal immunoglobulin domain. By making complementary mutations, we have shown that two charged residues in the CD48 ligand-binding site interact directly with two oppositely charged residues in CD2's ligand-binding site. These results indicate that the amino-terminal immunoglobulin domains of CD2 and CD48 bind each other in the same orientation as the CD2-CD2 crystal lattice interaction, strongly supporting the suggestion that CD2 interacts head-to-head with its ligand. Modelling CD48 onto the CD2 structure reveals that the CD2-CD48 complex spans approximately the same distance (134 A) as predicted for the complex between the T-cell receptor and the peptide-bound major histocompatibility complex (MHC) molecule. CONCLUSIONS: Our results, together with recent structural studies of CD2, provide the first indication of the specific topology of a cell-adhesion molecule complex. The similar dimensions predicted for the CD2-CD48 complex and the complex between the T-cell receptor and the peptide-bound MHC molecule suggest that one of the functions of CD2 may be to position the plasma membranes of the T cell and the antigen-presenting (or target) cell at the optimal distance for the low-affinity interaction between the T-cell receptor and the peptide-bound MHC molecule.

Influence of prolonged hospitalization on overall bed occupancy: a five-year single-centre study.

BACKGROUND: Effective bed use is crucial to an efficient NHS. Current targets suggest a decrease in mean occupancy as the most appropriate method of improving overall efficiency. The elderly and those suffering from complex medical problems are thought to account for a high proportion of overall bed occupancy. AIM: To assess the effect of prolonged hospital stay (>100 days) on overall bed occupancy in a modern teaching hospital. DESIGN: Retrospective analysis. METHODS: Analysis of all admission episodes (n = 117,178) over a five-year period in a large teaching hospital in a single UK region, serving a population of approximately 200,000. A logistic regression multi-factorial model was used to assess the effect of demographic and diagnostic variables on duration of stay. RESULTS: A prolonged stay (>100 days) was seen in 648 admission episodes (0.6%). These accounted for 11% of the overall bed occupancy over the 5-year period. Excluding all prolonged admission episodes from our analysis made no difference to the overall median length of stay. DISCUSSION: Prolonged hospitalizations have a significant impact on bed occupancy. Targeting these very long (>100 days) hospital stays may better improve overall efficiency, compared to targeting mean or median length of stay.

Screening for type 2 diabetes: literature review and economic modelling.

OBJECTIVES: To reconsider the aims of screening for undiagnosed diabetes, and whether screening should be for other abnormalities of glucose metabolism such as impaired glucose tolerance (IGT), or the 'metabolic syndrome'. Also to update the previous review for the National Screening Committee (NSC) on screening for diabetes, including reviewing choice of screening test; to consider what measures would be taken if IGT and impaired fasting glucose (IFG) were identified by screening, and in particular to examine evidence on treatment to prevent progression to diabetes in these groups; to examine the cost-effectiveness of screening; and to consider groups at higher risk at which screening might be targeted. DATA SOURCES: Electronic databases were searched up to the end of June 2005. REVIEW METHODS: Literature searches and review concentrated on evidence published since the last review of screening, both reviews and primary studies. The review of economic studies included only those models that covered screening. The new modelling extended an existing diabetes treatment model by developing a screening module. The NSC has a set of criteria, which it applies to new screening proposals. These criteria cover the condition, the screening test or tests, treatment and the screening programme. Screening for diabetes was considered using these criteria. RESULTS: Detection of lesser degrees of glucose intolerance such as IGT is worthwhile, partly because the risk of cardiovascular disease (CVD) can be reduced by treatment aimed at reducing cholesterol level and blood pressure, and partly because some diabetes can be prevented. Several trials have shown that both lifestyle measures and pharmacological treatment can reduce the proportion of people with IGT who would otherwise develop diabetes. Screening could be two-stage, starting with the selection of people at higher risk. The second-stage choice of test for blood glucose remains a problem, as in the last review for NSC. The best test is the oral glucose tolerance test (OGTT), but it is the most expensive, is inconvenient and has weak reproducibility. Fasting plasma glucose would miss people with IGT. Glycated haemoglobin does not require fasting, and may be the best compromise. It may be that more people would be tested and diagnosed if the more convenient test was used, rather than the OGTT. Five economic studies assessed the costs and short-term outcomes of using different screening tests. None examined the long-term impact of different proportions of false negatives. All considered the costs that would be incurred and the numbers identified by different tests, or different cut-offs. Results differed depending on different assumptions. They did not give a clear guide as to which test would be the best in any UK screening programme, but all recognised that the choice of cut-off would be a compromise between sensitivity and specificity; there is no perfect test. The modelling exercise concluded that screening for diabetes appears to be cost-effective for the 40-70-year age band, more so for the older age bands, but even in the 40-49-year age group, the incremental cost-effectiveness ratio for screening versus no screening is only 10,216 pounds per quality-adjusted life-year. Screening is more cost-effective for people in the hypertensive and obese subgroups and the costs of screening are offset in many groups by lower future treatment costs. The cost-effectiveness of screening is determined as much by, if not more than, assumptions about the degree of control of blood glucose and future treatment protocols than by assumptions relating to the screening programme. The very low cost now of statins is also an important factor. Although the prevalence of diabetes increases with age, the relative risk of CVD falls, reducing the benefits of screening. Screening for diabetes meets most of the NSC criteria, but probably fails on three: criterion 12, on optimisation of existing management of the condition; criterion 13, which requires that there should be evidence from high-quality randomised controlled trials (RCTs) showing that a screening programme would reduce mortality or morbidity; and criterion 18, that there should be adequate staffing and facilities for all aspects of the programme. It is uncertain whether criterion 19, that all other options, including prevention, should have been considered, is met. The issue here is whether all methods of improving lifestyles in order to reduce obesity and increase exercise have been sufficiently tried. The rise in overweight and obesity suggests that health promotion interventions have not so far been effective. CONCLUSIONS: The case for screening for undiagnosed diabetes is probably somewhat stronger than it was at the last review, because of the greater options for reduction of CVD, principally through the use of statins, and because of the rising prevalence of obesity and hence type 2 diabetes. However, there is also a good case for screening for IGT, with the aim of preventing some future diabetes and reducing CVD. Further research is needed into the duration of undiagnosed diabetes, and whether the rise in blood glucose levels is linear throughout or whether there may be a slower initial phase followed by an acceleration around the time of clinical diagnosis. This has implications for the interval after which screening would be repeated. Further research is also needed into the natural history of IGT, and in particular what determines progression to diabetes. An RCT of the type required by NSC criterion 13 is under way but will not report for about 7 years.

Cost-effectiveness of implementing automated grading within the national screening programme for diabetic retinopathy in Scotland.

AIMS: National screening programmes for diabetic retinopathy using digital photography and multi-level manual grading systems are currently being implemented in the UK. Here, we assess the cost-effectiveness of replacing first level manual grading in the National Screening Programme in Scotland with an automated system developed to assess image quality and detect the presence of any retinopathy. METHODS: A decision tree model was developed and populated using sensitivity/specificity and cost data based on a study of 6722 patients in the Grampian region. Costs to the NHS, and the number of appropriate screening outcomes and true referable cases detected in 1 year were assessed. RESULTS: For the diabetic population of Scotland (approximately 160,000), with prevalence of referable retinopathy at 4% (6400 true cases), the automated strategy would be expected to identify 5560 cases (86.9%) and the manual strategy 5610 cases (87.7%). However, the automated system led to savings in grading and quality assurance costs to the NHS of 201,600 pounds per year. The additional cost per additional referable case detected (manual vs automated) totalled 4088 pounds and the additional cost per additional appropriate screening outcome (manual vs automated) was 1990 pounds. CONCLUSIONS: Given that automated grading is less costly and of similar effectiveness, it is likely to be considered a cost-effective alternative to manual grading.

The efficacy of automated "disease/no disease" grading for diabetic retinopathy in a systematic screening programme.

AIM: To assess the efficacy of automated "disease/no disease" grading for diabetic retinopathy within a systematic screening programme. METHODS: Anonymised images were obtained from consecutive patients attending a regional primary care based diabetic retinopathy screening programme. A training set of 1067 images was used to develop automated grading algorithms. The final software was tested using a separate set of 14 406 images from 6722 patients. The sensitivity and specificity of manual and automated systems operating as "disease/no disease" graders (detecting poor quality images and any diabetic retinopathy) were determined relative to a clinical reference standard. RESULTS: The reference standard classified 8.2% of the patients as having ungradeable images (technical failures) and 62.5% as having no retinopathy. Detection of technical failures or any retinopathy was achieved by manual grading with 86.5% sensitivity (95% confidence interval 85.1 to 87.8) and 95.3% specificity (94.6 to 95.9) and by automated grading with 90.5% sensitivity (89.3 to 91.6) and 67.4% specificity (66.0 to 68.8). Manual and automated grading detected 99.1% and 97.9%, respectively, of patients with referable or observable retinopathy/maculopathy. Manual and automated grading detected 95.7% and 99.8%, respectively, of technical failures. CONCLUSION: Automated "disease/no disease" grading of diabetic retinopathy could safely reduce the burden of grading in diabetic retinopathy screening programmes.

Safety versus success in elective single embryo transfer: women's preferences for outcomes of in vitro fertilisation.

OBJECTIVE: To assess whether women waiting to undergo in vitro fertilisation (IVF) view adverse outcomes associated with twin pregnancy as more desirable than having no pregnancy at all. DESIGN: Women's preference values for five adverse birth outcomes associated with twin pregnancy were compared with their preference value for treatment failure (TF), i.e. no pregnancy at all. SETTING: Aberdeen Fertility Centre, University of Aberdeen, UK. POPULATION: A total of 74 women waiting to undergo IVF. METHODS: The standard gamble method was used to elicit women's preference values for giving birth to a child with physical impairments (PI), cognitive impairments (CI), or visual impairments (VI), perinatal death (PD) without a subsequent pregnancy, premature delivery (PremD), and TF (no pregnancy). MAIN OUTCOME MEASURES: Preference values were elicited on a scale where 1 represents giving birth to a healthy child and 0 represents immediate death. RESULTS: The median preference values for having a child with PI, CI, or VI were 0.940, 0.970, and 0.975, respectively. The median values for PremD, PD, and TF were 0.955, 0.725, and 0.815, respectively. Having no child at all was valued significantly lower than having a child with PI, CI, or VI (P < 0.01) but significantly higher than PD (P < 0.01). CONCLUSIONS: Some women waiting for IVF treatment view severe child disability outcomes associated with double embryo transfer as being more desirable than having no child at all. Women embarking on IVF may be influenced more strongly by considerations of 'treatment success' rather than future risks to their offspring.

Assessment of cosmetic ingredients in the in vitro reconstructed human epidermis test method EpiSkin™ using HPLC/UPLC-spectrophotometry in the MTT-reduction assay.

Cosmetics Europe recently established HPLC/UPLC-spectrophotometry as a suitable alternative endpoint detection system for measurement of formazan in the MTT-reduction assay of reconstructed human tissue test methods irrespective of the test system involved. This addressed a known limitation for such test methods that use optical density for measurement of formazan and may be incompatible for evaluation of strong MTT reducer and/or coloured chemicals. To build on the original project, Cosmetics Europe has undertaken a second study that focuses on evaluation of chemicals with functionalities relevant to cosmetic products. Such chemicals were primarily identified from the Scientific Committee on Consumer Safety (SCCS) 2010 memorandum (addendum) on the in vitro test EpiSkin™ for skin irritation testing. Fifty test items were evaluated in which both standard photometry and HPLC/UPLC-spectrophotometry were used for endpoint detection. The results obtained in this study: 1) provide further support for Within Laboratory Reproducibility of HPLC-UPLC-spectrophotometry for measurement of formazan; 2) demonstrate, through use a case study with Basazol C Blue pr. 8056, that HPLC/UPLC-spectrophotometry enables determination of an in vitro classification even when this is not possible using standard photometry and 3) addresses the question raised by SCCS in their 2010 memorandum (addendum) to consider an endpoint detection system not involving optical density quantification in in vitro reconstructed human epidermis skin irritation test methods.

Assessment of single vessel coronary artery disease: results of exercise electrocardiography, thallium-201 myocardial perfusion imaging and radionuclide angiography.

The sensitivity of the commonly used stress tests for the diagnosis of coronary artery disease was analyzed in 46 patients with significant occlusion (greater than or equal to 70% luminal diameter obstruction) of only one major coronary artery and no prior myocardial infarction. In all patients, thallium-201 perfusion imaging (both planar and seven-pinhole tomographic) and 12 lead electrocardiography were performed during the same graded treadmill exercise test and radionuclide angiography was performed during upright bicycle exercise. Exercise rate-pressure (double) product was 22,307 +/- 6,750 on the treadmill compared with 22,995 +/- 5,622 on the bicycle (p = NS). Exercise electrocardiograms were unequivocally abnormal in 24 patients (52%). Qualitative planar thallium images were abnormal in 42 patients (91%). Quantitative analysis of the tomographic thallium images were abnormal in 41 patients (89%). An exercise ejection fraction of less than 0.56 or a new wall motion abnormality was seen in 30 patients (65%). Results were similar for the right (n = 11) and left anterior descending (n = 28) coronary arteries while all tests but the planar thallium imaging showed a lower sensitivity for isolated circumflex artery disease (n = 7). The specificity of the tests was 72, 83, 89 and 72% for electrocardiography, planar thallium imaging, tomographic thallium imaging and radionuclide angiography, respectively. The results suggest that exercise thallium-201 perfusion imaging is the most sensitive noninvasive stress test for the diagnosis of single vessel coronary artery disease.

Assessment of myocardial systolic wall thickening using nuclear magnetic resonance imaging.

A quantitative nuclear magnetic resonance (NMR) imaging method of evaluating regional left ventricular function was compared with histochemical evidence of infarction in dogs and functional measurements in patients. Short-axis images of the heart were obtained at end-diastole and at 100 ms intervals thereafter. Regional diastolic left ventricular wall thickness and maximal percent systolic wall thickening were measured at the level of the papillary muscles in each of six segments. In six normal dogs, the mean end-diastolic wall thickness was 9 +/- 1.6 mm, and the mean maximal percent thickening was 61 +/- 11%. In eight dogs with a 4 day old infarct, maximal percent thickening was 5 +/- 8% (p less than 0.001) in the infarcted segments. In 10 normal human volunteers, the mean end-diastolic wall thickness was 10.1 +/- 1 mm, and the mean maximal percent systolic wall thickening was 60 +/- 18%. Reduced maximal percent systolic wall thickening was defined as a value greater than or equal to 2 SD below the mean value obtained in normal volunteers. Seven patients with regional wall motion abnormalities were independently assessed by NMR imaging and biplane ventriculography. With a sensitivity of 94% and a specificity of 80%, NMR imaging demonstrated reduced maximal percent systolic wall thickening in the same segments identified as akinetic or dyskinetic by biplane ventriculography. Thus, abnormalities of regional systolic wall thickening are accurately identified with this quantitative imaging technique.

A pragmatic randomised controlled trial of the cost-effectiveness of palliative therapies for patients with inoperable oesophageal cancer.

OBJECTIVES: To compare whether treatment with self-expanding metal stents (SEMS) is more cost-effective than treatment with conventional modalities in patients with inoperable oesophageal cancer. Quality of life effects were also considered. DESIGN: A multicentre pragmatic, randomised controlled trial with health economic analysis. SETTING: Seven NHS hospitals selected to represent a cross-section of UK hospitals in terms of facilities and staffing. PARTICIPANTS: All patients attending the centres with oesophageal cancer deemed unsuitable for surgery were assessed for inclusion in the main trial; 217 patients were randomised. A health state utilities substudy was also performed in 71 patients who had previously received curative surgery for oesophageal cancer. INTERVENTIONS: Eligible patients were randomised to one of four treatment groups within two study arms. Assessments were performed at enrolment, 1 week following treatment and thereafter at 6-weekly intervals until death, with prospective data collection on complications and survival. Structured interviews to elicit patient preferences to health states and treatments were performed in a substudy. MAIN OUTCOME MEASURES: Dysphagia grade and quality of life were examined at 6 weeks. Survival, resources consumed from randomisation to death and quality-adjusted life-years were also considered. RESULTS: There was no difference in cost or effectiveness between SEMS and non-SEMS therapies, and 18-mm SEMS had equal effectiveness to, but less associated pain than, 24-mm SEMS. Rigid intubation was associated with a worse quality of swallowing and increased late morbidity. Bipolar electrocoagulation and ethanol tumour necrosis were poor in primary palliation. A survival advantage was found for non-stent therapies, but there was a significant delay to treatment. The length of stay accounts for the majority of the cost to the NHS. Patients were found to have distinct individual treatment preferences. CONCLUSIONS: It was suggested that rigid tubes and 24-mm SEMS should no longer be recommended and bipolar electrocoagulation and ethanol tumour necrosis should not be used for primary palliation. The choice in palliation would between non-stent and 18-mm SEMS treatments, with non-stent therapies being made more available and accessible to reduce delay. A multidisciplinary team approach to palliation is also suggested. A randomised controlled clinical trial of 18-mm SEMS versus non-stent therapies with survival and quality of life end-points would be helpful, as would an audit of palliative patient admissions to determine the reasons and need for inpatient hospital care, with a view to implementing cycle-associated change to reduce inpatient stay. A study of delays in palliative radiotherapy treatment is also suggested, with a view to implementing cycle-associated change to reduce waiting time.

The effect of transferrin saturation on the estimation of erythropoietin by the mouse spleen cell microassay.

The effect of transferrin from various sources and the degree of saturation with iron on the stimulation of DNA synthesis by erythropoietin (Epo) has been investigated. Mouse, human, and bovine transferrins saturated with iron caused an increase in thymidine incorporation both in the absence and presence of Epo. In contrast, exogenous human and bovine apotransferrin resulted in significantly decreased incorporation of the tracer. The iron saturation of serum alters its apparent erythropoietic activity. This transferrin saturation effect may be overcome by a simple modification involving the addition of iron to the culture medium.

Use of HPLC/UPLC-spectrophotometry for detection of formazan in in vitro Reconstructed human Tissue (RhT)-based test methods employing the MTT-reduction assay to expand their applicability to strongly coloured test chemicals.

A number of in vitro test methods using Reconstructed human Tissues (RhT) are regulatory accepted for evaluation of skin corrosion/irritation. In such methods, test chemical corrosion/irritation potential is determined by measuring tissue viability using the photometric MTT-reduction assay. A known limitation of this assay is possible interference of strongly coloured test chemicals with measurement of formazan by absorbance (OD). To address this, Cosmetics Europe evaluated use of HPLC/UPLC-spectrophotometry as an alternative formazan measurement system. Using the approach recommended by the FDA guidance for validation of bio-analytical methods, three independent laboratories established and qualified their HPLC/UPLC-spectrophotometry systems to reproducibly measure formazan from tissue extracts. Up to 26 chemicals were then tested in RhT test systems for eye/skin irritation and skin corrosion. Results support that: (1) HPLC/UPLC-spectrophotometry formazan measurement is highly reproducible; (2) formazan measurement by HPLC/UPLC-spectrophotometry and OD gave almost identical tissue viabilities for test chemicals not exhibiting colour interference nor direct MTT reduction; (3) independent of the test system used, HPLC/UPLC-spectrophotometry can measure formazan for strongly coloured test chemicals when this is not possible by absorbance only. It is therefore recommended that HPLC/UPLC-spectrophotometry to measure formazan be included in the procedures of in vitro RhT-based test methods, irrespective of the test system used and the toxicity endpoint evaluated to extend the applicability of these test methods to strongly coloured chemicals.

Effect of immunosuppressive drug regime on cardiovascular risk profile following kidney transplantation.

We have previously studied cardiovascular risk markers apolipoprotein (a) (apo(a)) and plasma fibrinogen in 146 control, 60 haemodialysis (HD), 53 continuous ambulatory peritoneal dialysis (CAPD) and 66 renal transplant subjects. Fibrinogen concentration was higher in all 3 renal replacement groups compared to controls. Apo(a) was higher in the CAPD group only. We have now restudied those dialysis patients (24 HD, 16 CAPD) who have since undergone transplantation. Fibrinogen concentration remained elevated in CAPD patients (mean (SE) 3.9 (0.17) vs. 3.77 (0.20) grams/l) and increased in HD patients (2.88 (0.16) vs. 3.72 (0.13) grams/l, P < 0.0001). Apo(a) fell in both groups (CAPD, geometric mean 287 vs. 151 U/l, P = 0.008; HD, 230 vs. 179 U/l, P = 0.013). Fibrinogen concentration was higher in the recent group compared to the original group (3.74 (0.11) vs. 3.19 (0.12) grams/l, P = 0.001). None of the 66 original patients received cyclosporin (cyA) compared to 35 of the 40 in the present study. In this recent group, patients maintained on prednisolone and azathioprine alone had significantly lower fibrinogen levels than those receiving cyA. Furthermore, the fall in apo(a) was smaller (31% vs. 74%) and the increase in apolipoprotein B (apo B) greater (0.55 (0.15) vs. 0.18 (0.05) grams/l, P = 0.014) in cyA-treated patients. CyA may have an adverse effect on cardiovascular risk profile in renal transplant recipients.

Susceptibility of VLDL to oxidation in patients on regular haemodialysis.

Oxidation of VLDL in vitro increases macrophage uptake and promotes foam cell formation, and the dyslipidaemia of chronic renal failure is characterised by an increase in VLDL. However, little information is available with regard to the susceptibility of VLDL to oxidation in patients at increased risk of atherosclerosis. We have therefore assessed the composition and susceptibility to oxidation of VLDL from haemodialysis patients and control subjects. VLDL from haemodialysis patients contained increased lipid hydroperoxides (81.6 +/- 12.6 versus 16.1 +/- 3.4 nmol/mg protein, P < 0.001) and malondialdehyde (35.9 +/- 7.3 versus 16.0 +/- 4.1 nmol/mg protein, P < 0.05). Susceptibility to oxidation was increased as shown by an increased rate of propagation of the copper induced lipid peroxidation chain-reaction (11.6 +/- 1.5 x 10(-5) versus 7.6 +/- 1.1 x 10(-5)abs. U/min, P < 0.05) and a greater increase in conjugated diene formation during peroxidation (0.47 +/- 0.04 versus 0.25 +/- 0.03 abs. U, P < 0.001). Increased VLDL peroxidation in dialysis patients may contribute to the increased risk of cardiovascular disease observed in this group of patients.

Increased serum apolipoprotein(a) in patients with chronic renal failure treated with continuous ambulatory peritoneal dialysis.

Patients with end-stage renal failure (ESRF) on renal replacement therapy are at significantly increased risk of cardiovascular disease. To determine whether altered concentrations of apolipoprotein(a) (apo(a)), the plasminogen-like protein moiety of the atherogenic particle lipoprotein(a), contributed to this increased risk, apo(a) concentrations were measured in 48 non-diabetic patients with ESRF treated by continuous ambulatory peritoneal dialysis (CAPD) therapy and compared with 65 controls. Apo(a) concentration was increased in CAPD patients compared to controls (geometric mean 419 units/l versus 137 units/l; ratio of means 3.06 (95% CI 1.95-4.80). We conclude that CAPD patients have increased apo(a) concentrations which may contribute to their increased risk of cardiovascular disease.