Soya isoflavone-enriched cereal bars affect markers of endothelial function in postmenopausal women

Soya isoflavones are thought to be cardioprotective due to their structural similarity to oestrogen. In order to investigate the effect of soya isoflavones on markers of endothelial function we conducted a randomised, double-blind, placebo-controlled, cross-over study with thirty healthy postmenopausal women. The women consumed cereal bars, with or without soya isoflavones (50 mg/d), for 8 weeks, separated by an 8-week washout period. Systemic arterial compliance (SAC), isobaric arterial compliance (IAC), flow-mediated endothelium-dependent vasodilation (FMD) and nitroglycerine-mediated endothelium-independent vasodilation (NMD) were measured at the beginning of the study and after each intervention period. Blood pressure (BP) and plasma concentrations of nitrite and nitrate (NOx) and endothelin-1 (ET-1) were measured at the beginning and end of each intervention period. NMD was 13.4 (SEM 2.0)% at baseline and 15.5 (SEM 1.1) % after isoflavone treatment compared with 12.4 (SEM 1.0)% after placebo treatment (P=0.03). NOx increased from 27.7 (SEM 2.7) to 31.1 (SEM 3.2) microM after isoflavones treatment compared with 25.4 (SEM 1.5) to 20.4 (SEM 1.1) microM after placebo treatment (P=0.003) and a significant increase in the NOx:ET-1 ratio (P=0.005) was observed after the isoflavone treatment compared with placebo. A significant difference in SAC after the isoflavone and placebo treatment was observed (P=0.04). No significant difference was found in FMD, IAC, BP and ET-1. In conclusion, 8 weeks' consumption of cereals bars enriched with 50 mg soya isoflavones/d increased plasma NOx concentrations and improved endothelium-independent vasodilation in healthy postmenopausal women.

Variation in organ donation in northeastern England 1986 to 2003

Renal transplantation is established as the best form of renal replacement therapy, but demand for kidneys exceeds supply from cadaveric donations. It is therefore important to make the best use of the pool of potential cadaveric organ donors. Donation rates are to a large extent dependent on public opinions, which may be influenced by external events. In northeast England from 1986 to 2003, there was a potential pool of 1170 brain stem-dead donors, of whom 190 (16%) could not be retrieved due to relatives' objections. From 1998 to 2003 we were referred 90 potential non-heart-beating donors, of whom relatives refused donation in 10 (11%). A major reason for not retrieving organs from a potential donor has been lack of consent from the relatives. Refusals appear to vary year by year and are consistently lower for non-heart-beating donors. This therefore raises the possibility that negative or positive media publicity plays a role in this variation.

Cardiovascular risk assessment scoring system for the determination of cardiovascular mortality in renal transplant patients

It is well known that the greatest risk for mortality post-renal transplant is cardiovascular death. We compared a modified cardiac risk assessment system among renal transplant patients who subsequently died versus the group that survived. There was a good correlation between the low, medium, and high scores with survival. The deceased group had significantly greater cardiovascular scores than case controls.

A simple cardiovascular risk score can predict poor outcome in NHBD renal transplantation

A simple cardiovascular risk score used in our center to plan cardiovascular workup for renal transplantation can predict outcome in non-heart-beating donor (NHBD) renal transplantation. Patients in the higher risk group, with a score of >12 out of a maximum of 36 are likely to have a longer duration of delayed graft function, poorer glomerular filtration rate at 6 months, and inferior graft and patient survival, together with an relative rate of graft loss within 60 days of >4 (P = .053). Although a high cardiovascular risk score should not be regarded as a contraindication to NHBD transplantation, the score can be used to facilitate recipient selection.

Ischemia-reperfusion injury in cadaveric nonheart beating, cadaveric heart beating and live donor renal transplants

PURPOSE

Ischemia-reperfusion injury is gaining importance in transplantation as being responsible for allograft dysfunction. Ischemia occurs during kidney procurement, which is shortest in LDs, and prolonged in cadaveric HBDs and NHBDs.

MATERIALS AND METHODS

Renal transplants from 17 LDs, 15 HBDs and 19 NHBDs were assessed during reperfusion for biochemical markers of ischemia-reperfusion injury and assessed clinically. Central venous blood sampling was assayed for free radicals using electron spin resonance and tissue injury biomarkers, namely lactate dehydrogenase, fatty acid binding protein, alanine aminopeptidase, lactate and total antioxidants.

RESULTS

The return to stable renal function was more rapid in LD renal transplants, while recovery continued from 3 months after hospital discharge in NHBD renal transplants. Injury markers, such as lactate dehydrogenase, fatty acid binding protein, alanine aminopeptidase and lactate, were raised at the time of reperfusion, especially in NHBD renal transplants. Free radical release measured by electron spin resonance showed 2 phase release, that is early (0 to 10-minute) and late (20 to 40-minute) release. In NHBD, HBD and LD renal transplants the index of free radical release in the early phase was 1.43, 1.36 and 1.20, and in the late phase it was 1.43, 1.38 and 0.97, respectively (each ANOVA p <0.05).

CONCLUSIONS

NHBD renal transplants were accompanied by a greater release of free radicals at reperfusion (NHBD > HBD > LD), which was associated with an increase in tissue injury markers at reperfusion. This was reflected in a slower return to stable renal function in NHBD compared to HBD and LD renal transplants.

Anti-vimentin Antibody Detection in Recipients of Heart-Beating and Non–Heart Beating Donor Kidneys

Alternative donor sources include non-heart-beating donors (NHBDs). There donors have been exposed to significant ischemia, so that it is common to utilize machine perfusion to either improve the organs or at least assess their viability. Both prolonged warm ischemia and machine perfusion can potentially damage the vascular endothelium, thereby exposing vimentin to antigenic recognition. The aim of this study was to determine whether anti-vimentin antibodies could be detected in the blood of renal transplant recipients at specific time points after transplant and whether they could be related to the donor source. Fifty-one recipients of NHBD kidneys were compared to 52 recipients of heart-beating donor (HBD) kidneys. All recipients had similar anti-vimentin levels pretransplant. However, at 1 month those kidneys from Maastricht category II NHB donors showed significantly higher levels. At 6 months both Maastricht category II and category III NHB donor recipients displayed significantly higher levels than recipients of HBD kidneys.

Do Recipients of Kidneys From Donors Treated With Streptokinase Develop Anti-streptokinase Antibodies?

Streptokinase is used for preflush for non-heart-beating donors (NHBDs) in our center. The aim of this study was to evaluate whether the use of thrombolytic streptokinase results in the production of anti-streptokinase antibodies in the recipients after renal transplantation. Recipient sera taken prior to and at 1 and 6 months posttransplant were tested for the presence of antibodies to streptokinase using an enzyme-linked immunosorbent assay assay. No differences were detected between a group of 18 recipients who had kidneys from thrombolytic-treated NHBDs and a further group of 18 who received NHBD kidneys without such treatment.

Audit of Diabetes in a Renal Transplant Population

AIMS

To determine the prevalence of diabetes and its glycemic control in the renal transplant population of northeast England (Newcastle, Sunderland, Middlesborough, and Carlisle).

METHODS

All renal transplant notes in northeast England were reviewed. Data on patient details, type of diabetes, time of onset of diabetes, diabetes medications, time of insulin commencement, date of renal transplant, immunosuppressive medications, and HbA(1C) were recorded.

RESULTS

Living renal transplant patients (n = 1073) transplanted between March 1982 and November 5, 2003 were identified. One hundred and nine (10.2%) patients had diabetes, of whom 39 were type 1 and 70 were type 2. Median HBA(1C) in patients with type 1 diabetes on tacrolimus was 10.1% +/- 1.94% (SD) versus 7.8% +/- 1.98% (SD) for patients not on tacrolimus. Among patients with type 2 diabetes, 25 had diabetes prior to transplant and 45 (4.5%) developed posttransplant diabetes (PTDM). Those who developed PTDM and were taking tacrolimus were more likely to require insulin for blood glucose control (0.39 U/kg/24 hours vs 0 U/kg/24 hours; P = .05) compared to those not on tacrolimus. Both type 1 and type 2 diabetics on tacrolimus showed better preservation of renal function as measured by mean serum creatinine (type 1: 145 +/- 53 vs 196 +/- 74, P = .02; type 2 pretransplant: 159 +/- 73 vs 172 +/- 59, P = .35; type 2 posttransplant: 123 +/- 35 vs 167 +/- 63, P = .01).

CONCLUSIONS

Tacrolimus use in renal transplant patients with diabetes appeared to be associated with more problematic blood glucose control; however, it seemed to be better at preserving renal function. Intensive blood glucose monitoring is recommended for this group.

Does Donor Cardiopulmonary Resuscitation Time Affect Outcome in Uncontrolled Non–Heart-Beating Donor Renal Transplants?

Uncontrolled non-heart-beating donors offer the opportunity to significantly expand the potential pool of kidney donors but are associated with a variable duration of cardiopulmonary resuscitation (CPR), where cardiac output is only 30% to 40% of normal. We were concerned that prolonged CPR would adversely affect the function of transplanted kidneys. In our series of 46 uncontrolled donors the mean duration of CPR was 60 minutes, which also represents a realistic cutoff point for CPR duration. Taking a cutoff point of 60 minutes, we found no differences in kidney discard rates following viability assessment, primary nonfunction rate, or duration of delayed graft function. We therefore conclude that if formal viability assessment is performed, kidneys may be retrieved from uncontrolled non-heart-beating donors irrespective of duration of CPR.

Evaluation of daclizumab to reduce delayed graft function in non-heart-beating renal transplantation: a prospective, randomized trial

Daclizumab (DZB), an interleukin-2 receptor blocker, has been shown to reduce the rate of acute rejection, while non-heart-beating kidney recipients have high rates of delayed graft function that may be prolonged by high levels of calcineurin inhibitors. This study assessed whether DZB could safely replace calcineurin inhibitors in the immediate postoperative period and promote recovery from ischemic acute tubular necrosis. Patients were randomized into one of two groups: DZB induction and daily mycophenolate mofetil (MMF; 2 g) with steroids (20 mg prednisone) or standard triple therapy with tacrolimus, MMF, and prednisone. Patients in the DZB arm were converted to the control arm when either the serum creatinine dropped to <350 micromol/L or there was biopsy evidence of acute rejection. Over 2 years, Leicester and Newcastle non-heart-beating donor (NHBD) centers recruited 51 patients. There was one patient death in the DZB arm, during the study period, after a nonfunctioning graft was removed. A total of two (8%) grafts in the DZB arm and three (11.5%) grafts in the control arm failed to function. The overall rate of immediate function improved from around 5% (pre-2001) to 28%. There were no significant differences in the incidence of acute rejection or graft function (GFR) at 3 months. Machine-perfused kidneys in DZB-treated recipients had the highest rates of immediate function (53%, P = .015). We found that a calcineurin-sparing regime is safe and may be beneficial for recipients of machine-perfused grafts damaged by warm ischemia.

Randomized clinical trial of daclizumab induction and delayed introduction of tacrolimus for recipients of non-heart-beating kidney transplants

Background

Kidneys from non-heart-beating donors (NHBDs) have high rates of delayed graft function (DGF). Use of calcineurin inhibitors is associated with a reduction in renal blood flow, which may delay graft recovery from ischaemic acute tubular necrosis.

Methods

To assess whether daclizumab (DZB) could safely replace tacrolimus in the immediate postoperative period, patients were randomized to receive DZB induction and daily mycophenolate mofetil with steroids (DZB group) or standard tacrolimus-based triple therapy (control group). Tacrolimus was given to patients in the DZB group when the serum creatinine level dropped below 350 µmol/l.

Results

Fifty-one patients were recruited at two centres over a 2-year interval between 2000 and 2003. The overall rate of immediate function was 28 per cent (13 of 46 grafts), with the highest rate in recipients of machine-perfused kidneys treated with DZB (eight of 15 patients).

Conclusion

Induction with DZB and delayed introduction of tacrolimus reduced the incidence of DGF in recipients of machine-perfused NHBD kidneys.

A Simple Cardiovascular Risk Score Can Predict Poor Outcome in Non–Heart-Beating Donor Renal Transplantation

A simple cardiovascular risk score used in our centre to plan cardiovascular work-up for renal transplantation can predict outcome in non-heart-beating donor (NHBD) renal transplantation. Patients in the higher-risk group, with a score of >12 of a maximum of 36 are likely to have a longer duration of delayed graft function, poorer glomerular filtration rate at 6 months, and inferior graft and patient survival, together with a relative rate of graft loss within 60 days of 4.514 (P = .019) and within 1 year of 3.511 (P = .036). Although a high cardiovascular risk score should not be regarded as a contraindication to NHBD transplantation, the score can be used to facilitate recipient selection.

Vimentin Antibodies: A Non-HLA Antibody as a Potential Risk Factor in Renal Transplantation

Chronic allograft rejection is the major problem encountered in solid organ transplantation and is the end point of several complex processes. A number of recent studies show both alloimmune and autoimmune responses may have roles to play. The importance of HLA antibodies in transplantation is well documented, but despite the introduction of very sensitive HLA screening assays, antibody-mediated allograft rejection still occurs without detectable HLA antibodies. The target for antibody-mediated allograft rejection in these circumstances remains elusive, perhaps due to the variety of potential targets presented on endothelial cells. Recent studies identifying C4d and immunoglobulin deposits in patients undergoing late allograft loss provide evidence that chronic rejection involves humoral as well as cellular components. Several endothelial cell antigens that might be important in chronic rejection have been suggested, including MHC class I chain-related genes; Lewis; and the intermediate filament protein, vimentin. Vimentin is an ideal candidate antigen for antibody-mediated rejection as it is found in endothelial cells and is exposed to the immune system following surgery or by chronic allograft rejection due to endothelial cell breakdown, where the development of antibodies may cause further damage. We have developed a flow cytometric assay for the detection of antibodies to vimentin and have investigated whether HLA or vimentin antibodies are present in renal transplant recipients undergoing chronic rejection.

Factors predicting duration of delayed graft function in non-heart-beating donor kidney transplantation

Non-heart-beating donors (NHBDs) are an important potential source of donor organs, but kidneys from such donors are prone to delayed graft function (DGF) and primary nonfunction, which are multifactorial in origin but believed to be mainly due to warm ischemic injury. This retrospective study examined a series of 88 transplants from Maastricht category II and III NHBDs to examine the role of factors to predict the duration of DGF. The main factors affecting duration of DGF were total warm ischemic time, cold ischemic time, product of perfusate GST concentration and donor age, quality of postoperative graft perfusion, incidence of acute rejection, recipient cardiovascular risk score, maximum pressure on machine perfusion, and weight gain during machine perfusion. Primary nonfunction was not accurately predicted from these factors for kidneys that had passed the viability assessment.

Dynamic EBV gene loads in renal, hepatic, and cardiothoracic transplant recipients as determined by real-time PCR light cycler

BACKGROUND

Epstein-Barr virus (EBV) is recognised as one of the causative agents for most cases of post-transplant lymphoproliferative disease (PTLD). Elevated levels of EBV DNA are known to be associated with the onset of PTLD, but little information is available regarding how EBV loads change with time in asymptomatic transplant recipients following transplantation. Our aims were to study the trend of EBV loads in renal (RTx), hepatic, and cardiothoracic transplant recipients and to compare their EBV loads with other healthy and patient controls.

METHODS

A prospective study was performed using a real-time TaqMan polymerase chain reaction technique to measure EBV DNA loads from three types of organ transplant recipients and haemodialysis patients (HD). Their results were then compared with those from the healthy controls (HC); monospot test negative (MN-) and infectious mononucleosis positive (IM+) patients; patients who were previously treated for PTLD (pPTLD); those who were currently diagnosed to have PTLD (PTLD+); and patients who had a stable renal, hepatic, or cardiothoracic graft for more than a year.

RESULTS

Post-transplant EBV loads were significantly higher than the pre-transplant levels. Asymptomatic transplant recipients were differentiated from the PTLD+group at 600 genome copies of EBV/mug DNA, and from IM+group at 100 genome copies. Both HC and MN- groups had significantly lower EBV loads than the three transplant groups. The dynamic change of EBV loads in RTx was greater in the first post-transplant month when compared with the HD group. All transplant recipients had transient rises of EBV loads whereas EBV load continued to rise in one suspected PTLD patient.

CONCLUSIONS

Asymptomatic transplant recipients had higher baseline post-transplant EBV levels than the non-transplant and MN- groups. The rising post-transplant EBV load in these transplant recipients did not seem to be sustained for longer than 2 weeks. However, in a PTLD+patient the rising EBV load continued over a period of 4 weeks. Hence, the dynamic pattern of EBV loads is more important than absolute EBV DNA measurements alone in identifying those who might go on to develop PTLD.

Synthesis and dispersion of Ni(OH)2 platelet-like nanoparticles in water

Synthesis of nanometric platelet-like Ni(OH)2 particles is described. The role of several experimental parameters on the particle size is investigated. A colloidal dispersion of particles is produced by adsorbing ionizable organic ligands (trisodium citrate) on the particle surface. The stability of this colloidal dispersion and the particle charge density are determined for different citrate ions concentrations.

Reperfusion injury in renal transplantation: comparison of LD, HBD and NHBD renal transplants

Comparison of reperfusion injury in kidneys transplanted from LD, HBD or NHBD donors is presented in the paper. Central venous blood samples (taken during perioperative period) was assessed for free radicals, total antioxidant activity and various markers of tissue injury. There was demonstrable ischemia reperfusion injury occurring at the time of revascularization, which was particularly notable in kidneys transplanted from NHBD donors.