The incremental yield of prenatal exome sequencing over chromosome microarray for congenital heart abnormalities: A systematic review and meta-analysis

OBJECTIVES

To determine the incremental yield of prenatal exome sequencing (PES) over standard testing in fetuses with an isolated congenital heart abnormality (CHA), CHA associated with extra-cardiac malformations (ECMs) and CHA dependent upon anatomical subclassification.

METHODS

A systematic review of the literature was performed using MEDLINE, EMBASE, Web of Science and grey literature January 2010-February 2023. Studies were selected if they included greater than 20 cases of prenatally diagnosed CHA when standard testing (QF-PCR/chromosome microarray/karyotype) was negative. Pooled incremental yield was determined. PROSPERO CRD 42022364747.

RESULTS

Overall, 21 studies, incorporating 1957 cases were included. The incremental yield of PES (causative pathogenic and likely pathogenic variants) over standard testing was 17.4% (95% CI, 13.5%-21.6%), 9.3% (95% CI, 6.6%-12.3%) and 35.9% (95% CI, 21.0%-52.3%) for all CHAs, isolated CHAs and CHAs associated with ECMs. The subgroup with the greatest yield was complex lesions/heterotaxy; 35.2% (95% CI 9.7%-65.3%). The most common syndrome was Kabuki syndrome (31/256, 12.1%) and most pathogenic variants occurred de novo and in autosomal dominant (monoallelic) disease causing genes (114/224, 50.9%).

CONCLUSION

The likelihood of a monogenic aetiology in fetuses with multi-system CHAs is high. Clinicians must consider the clinical utility of offering PES in selected isolated cardiac lesions.

Current Techniques and Indications for Machine Perfusion and Regional Perfusion in Deceased Donor Liver Transplantation

Since the advent of University of Wisconsin preservation solution in the 1980s, clinicians have learned to work within its confines. While affording improved outcomes, considerable limitations still exist and contribute to the large number of livers that go unused each year, often for fear they may never work. The last 10 years have seen the widespread availability of new perfusion modalities which provide an opportunity for assessing organ viability and prolonged organ storage. This review will discuss the role of in situ normothermic regional perfusion for livers donated after circulatory death. It will also describe the different modalities of ex situ perfusion, both normothermic and hypothermic, and discuss how they are thought to work and the opportunities afforded by them.

D-dimer Release From Livers During Ex Situ Normothermic Perfusion and After In Situ Normothermic Regional Perfusion: Evidence for Occult Fibrin Burden Associated With Adverse Transplant Outcomes and Cholangiopathy

BACKGROUND

Deceased donor livers are prone to biliary complications, which may necessitate retransplantation, and we, and others, have suggested that these complications are because of peribiliary vascular fibrin microthrombi. We sought to determine the prevalence and consequence of occult fibrin within deceased donor livers undergoing normothermic ex situ perfusion (NESLiP) and evaluate a role for fibrinolysis.

METHODS

D-dimer concentrations, products of fibrin degradation, were assayed in the perfusate of 163 livers taken after 2 h of NESLiP, including 91 that were transplanted. These were related to posttransplant outcomes. Five different fibrinolytic protocols during NESLiP using alteplase were evaluated, and the transplant outcomes of these alteplase-treated livers were reviewed.

RESULTS

Perfusate D-dimer concentrations were lowest in livers recovered using in situ normothermic regional perfusion and highest in alteplase-treated livers. D-dimer release from donation after brain death livers was significantly correlated with the duration of cold ischemia. In non-alteplase-treated livers, Cox proportional hazards regression analysis showed that D-dimer levels were associated with transplant survival ( P  = 0.005). Treatment with alteplase and fresh frozen plasma during NESLiP was associated with significantly more D-dimer release into the perfusate and was not associated with excess bleeding postimplantation; 8 of the 9 treated livers were free of cholangiopathy, whereas the ninth had a proximal duct stricture.

CONCLUSIONS

Fibrin is present in many livers during cold storage and is associated with poor posttransplant outcomes. The amount of D-dimer released after fibrinolytic treatment indicates a significant occult fibrin burden and suggests that fibrinolytic therapy during NESLiP may be a promising therapeutic intervention.

Predicting Early Allograft Function After Normothermic Machine Perfusion

BACKGROUND

Normothermic ex situ liver perfusion is increasingly used to assess donor livers, but there remains a paucity of evidence regarding criteria upon which to base a viability assessment or criteria predicting early allograft function.

METHODS

Perfusate variables from livers undergoing normothermic ex situ liver perfusion were analyzed to see which best predicted the Model for Early Allograft Function score.

RESULTS

One hundred fifty-four of 203 perfused livers were transplanted following our previously defined criteria. These comprised 84/123 donation after circulatory death livers and 70/80 donation after brain death livers. Multivariable analysis suggested that 2-h alanine transaminase, 2-h lactate, 11 to 29 mmol supplementary bicarbonate in the first 4 h, and peak bile pH were associated with early allograft function as defined by the Model for Early Allograft Function score. Nonanastomotic biliary strictures occurred in 11% of transplants, predominantly affected first- and second-order ducts, despite selection based on bile glucose and pH.

CONCLUSIONS

This work confirms the importance of perfusate alanine transaminase and lactate at 2-h, as well as the amount of supplementary bicarbonate required to keep the perfusate pH > 7.2, in the assessment of livers undergoing perfusion. It cautions against the use of lactate as a sole indicator of viability and also suggests a role for cholangiocyte function markers in predicting early allograft function.

Perceptions of an eHealth family-based cardiovascular disease risk reduction intervention: a mixed methods study

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): Department for the Economy, Northern Ireland

Introduction

Controllable cardiovascular disease (CVD) risk factors are often initiated in the family home, yet risk reduction is seldom targeted toward families. Participatory design of eHealth interventions with end-users has potential to increase acceptability and adherence of such interventions. Despite their shared risk of developing CVD, few eHealth interventions target both parents and children at CVD risk. Therein lies an evidence gap; the need for coproduction of a family-based eHealth intervention aimed at early CVD prevention.

Purpose

The aim of this study was to identify the perceptions of families towards the design, functionality and acceptability of an eHealth, family-based, CVD prevention intervention.

Methods

Thee online focus groups comprising six families were conducted between April and May 2021. Families consisted of at least one parent who met CVD risk factor criteria, and at least one child aged five to 17 years. Content analysis and narrative synthesis were used to identify categories and subcategories regarding development of and engagement with the proposed intervention. Additionally, quantitative, and demographic measures were used to determine psychosocial and health profiles.

Results

Three categories were identified from the focus groups:

1) previous experiences of using health-related apps or devices

2) expectations of a newly developed eHealth family-based CVD prevention intervention

3) motivators for engagement with the intervention

Goal setting, rewards, accountability, adaptability, recording achievements and competition were considered crucial motivators for engagement for both parents and children. Participants welcomed the intervention, and advised they would prefer a free, personalised, easy-to-use, non-time-consuming intervention, with multiple content formats, and additional information available should they seek to access it. Parents conveyed satisfactory general self-efficacy and quality of life, low anxiety and depression and high perceived social support.

Conclusions

Overall, families were constructive and forthcoming towards the idea of an eHealth, family-based CVD prevention intervention. These findings informed a prototype of a family-based eHealth intervention aimed at early CVD prevention. The prototype is currently being developed with plans for piloting via a randomised controlled trial in the home environment, by families as an early intervention for the prevention of CVD.

First World Consensus Conference on pancreas transplantation: Part II - recommendations

The First World Consensus Conference on Pancreas Transplantation provided 49 jury deliberations regarding the impact of pancreas transplantation on the treatment of diabetic patients, and 110 experts' recommendations for the practice of pancreas transplantation. The main message from this consensus conference is that both simultaneous pancreas-kidney transplantation (SPK) and pancreas transplantation alone can improve long-term patient survival, and all types of pancreas transplantation dramatically improve the quality of life of recipients. Pancreas transplantation may also improve the course of chronic complications of diabetes, depending on their severity. Therefore, the advantages of pancreas transplantation appear to clearly surpass potential disadvantages. Pancreas after kidney transplantation increases the risk of mortality only in the early period after transplantation, but is associated with improved life expectancy thereafter. Additionally, preemptive SPK, when compared to SPK performed in patients undergoing dialysis, appears to be associated with improved outcomes. Time on dialysis has negative prognostic implications in SPK recipients. Increased long-term survival, improvement in the course of diabetic complications, and amelioration of quality of life justify preferential allocation of kidney grafts to SPK recipients. Audience discussions and live voting are available online at the following URL address: http://mediaeventi.unipi.it/category/1st-world-consensus-conference-of-pancreas-transplantation/246.

Family-based eHealth interventions to reduce cardiovascular disease risk: a systematic review

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): Department for the Economy, Northern Ireland

Background

Family-based eHealth interventions have potential to reduce cardiovascular disease (CVD) risk and improve health of parents and children.

Purpose

To evaluate the effectiveness of family-based eHealth interventions to reduce parent and child CVD risk.

Methods

Systematic review. Five electronic databases were searched (CENTRAL; MEDLINE; CINAHL; EMBASE; PsycINFO) up to April 2020. Data extraction included: study design, setting, methodology, eHealth technology, experiment/control group constituents, risk factors, outcomes, incentivisation and limitations. Data were synthesised narratively. Cochrane methodology was used to assess risk of bias and reporting quality.

Results

In total, 2193 articles were screened and seven trials included for review. The most consistently improved CVD risk factor across parents and children was reduced alcohol use, whilst reduction in BMI the least consistently improved. Behaviour-change theoretical underpinning, extended follow-up duration, interactivity and incentivisation were identified as effective components of these interventions. Four studies were assessed as overall ‘low risk’ of bias and three studies had concerns with randomisation and intention-to-treat analysis. Conclusions: This is the first systematic review to evaluate family-based eHealth interventions to reduce CVD risk. Despite a paucity in high-quality trials, there is evidence of their potential effectiveness. Recommended, more high quality, behaviour-change-theory-based, clearly reported interventions with explicit outcomes.

Flavin Mononucleotide as a Biomarker of Organ Quality-A Pilot Study

BACKGROUND

Flavin mononucleotide (FMN), released from damaged mitochondrial complex I during hypothermic liver perfusion, has been shown to be predictive of 90-day graft loss. Normothermic machine perfusion (NMP) and normothermic regional perfusion (NRP) are used for organ reconditioning and quality assessment before transplantation. This pilot study aimed to investigate the changes of FMN levels during normothermic reperfusion of kidneys, livers, and lungs and examine whether FMN could serve as a biomarker to predict posttransplant allograft quality.

METHODS

FMN concentrations, in perfusates collected during NMP of kidneys, abdominal NRP, and ex vivo lung perfusion, were measured using fluorescence spectrometry and correlated to the available perfusion parameters and clinical outcomes.

RESULTS

Among 7 transplanted kidneys out of the 11 kidneys that underwent NMP, FMN levels at 60 minutes of NMP were significantly higher in the allografts that developed delayed graft function and primary nonfunction (P = 0.02). Fifteen livers from 23 circulatory death donors that underwent NRP were deemed suitable for transplantation. Their FMN levels at 30 minutes of NRP were significantly lower than those not procured for transplantation (P = 0.004). In contrast, little FMN was released during the 8 lung perfusions.

CONCLUSIONS

This proof of concept study suggested that FMN in the perfusates of kidney NMP has the potential to predict posttransplant renal function, whereas FMN at 30 minutes of NRP predicts whether a liver would be accepted for transplantation. More work is required to validate the role of FMN as a putative biomarker to facilitate safe and reliable decision-making before embarking on transplantation.

P3417Comparison of cardiometabolic profile and left ventricular systolic dysfunction amongst outpatients in a low-income Sub-Saharan African versus high-income European population; the MTIMA I study

Background

Most of the information on modifiable risk factors linked to cardiac dysfunction comes from high income countries and/or hospitalized patients. We sought to evaluate the challenge of non-communicable diseases (NCDs) in the community setting in Malawi, and to compare the cardiometabolic profile of these patients with age, sex and diabetes matched European participants.

Methods

MTIMA I is a prospective, observational, cohort study of community dwelling patients attending a NCD clinic in Malawi together with age, sex and diabetes matched European participants. All consenting patients were evaluated for clinical history, blood pressure, heart rate, body mass index (BMI), fasting glucose, left ventricular ejection fraction and medications.

Results

Amongst 251 sub-Saharan African patients and 502 age, sex and diabetes matched European patients, the average age was 61.8±10.6 years, 31% were male and 53% had diabetes and the majority had hypertension (80.0% and 70.7% in the African and European cohorts respectively, p=NS). The African population had poorer pressure control (147/90±21/13 mmHg vs 137/82±19/11 mmHg, p<0.0001) and higher heart rates (80.73±17.0 bpm vs 72.7±12.5 bpm, p<0.0001) than the European cohort. Use of antihypertensive agents per patient was lower in the African population (0.96±0.05 vs 1.22±0.05, p<0.001) and there was lower usage of renin-angiotensin-aldosterone-system modifying therapies. Reported smoking rates were lower in the African cohort (3% vs 16%, p<0.0001). Only 78 of the African cohort had lipids evaluated compared with all the European cohort and in this subset, while total cholesterol was lower (4.4±1.2, vs. 4.6±0.5 mmol/L, p<0.01), it was due to lower HDL (0.99±0.5 vs 1.3±0.2 mmol/L, p<0.001) as LDL cholesterol was similar (2.6±1.0, vs 2.5±0.5 mmol/L, p=ns). Statin usage was lower in the African cohort (1.6% vs 61.5%, p<0.0001). Surprisingly, the average body mass index did not differ between the populations (28.9±0.3 vs 29.2±1.5 kg/m2, p=NS) and there were similar proportions of obesity (31.1% vs 33.7%). Plasma glucose was higher in the African population (10.3±0.4 vs. 7.4±0.1 mmol/L, p<0.0001) despite similar usage of antidiabetic therapies. Average ejection fraction was significantly lower in the African cohort (49.8±8.6% vs 66.5±3.5%, p<0.0001). Left ventricular systolic dysfunction (<40%) was significantly more prevalent in the African cohort (21% vs 0.4%, p<0.0001).

Conclusions

The profile of cardiovascular risk factors, medications and cardiac dysfunction is different in community dwelling African and European patients with chronic cardiovascular disease. One in 5 African patients in our study has undiagnosed left ventricular systolic dysfunction reflecting the need for increased focus on non-communicable diseases and cardiovascular prevention. Further work on the pathophysiology of the high rate of LVSD noted and prevention strategies are required

Nitrogen use efficiency and nitrous oxide emissions from five UK fertilised grasslands

Intensification of grasslands is necessary to meet the increasing demand of livestock products. The application of nitrogen (N) on grasslands affects the N balance therefore the nitrogen use efficiency (NUE). Emissions of nitrous oxide (N₂O) are produced due to N fertilisation and low NUE. These emissions depend on the type and rates of N applied. In this study we have compiled data from 5 UK N fertilised grassland sites (Crichton, Drayton, North Wyke, Hillsborough and Pwllpeiran) covering a range of soil types and climates. The experiments evaluated the effect of increasing rates of inorganic N fertiliser provided as ammonium nitrate (AN) or calcium ammonium nitrate (CAN). The following fertiliser strategies were also explored for a rate of 320 kg N ha^-1: using the nitrification inhibitor dicyandiamide (DCD), changing to urea as an N source and splitting fertiliser applications. We measured N₂O emissions for a full year in each experiment, as well as soil mineral N, climate data, pasture yield and N offtake. N₂O emissions were greater at Crichton and North Wyke whereas Drayton, Hillsborough and Pwllpeiran had the smallest emissions. The resulting average emission factor (EF) of 1.12% total N applied showed a range of values for all the sites between 0.6 and 2.08%. NUE depended on the site and for an application rate of 320 kg N ha^-1, N surplus was on average higher than 80 kg N ha^-1, which is proposed as a maximum by the EU Nitrogen Expert Panel. N₂O emissions tended to be lower when urea was applied instead of AN or CAN, and were particularly reduced when using urea with DCD. Finally, correlations between the factors studied showed that total N input was related to Nofftake and Nexcess; while cumulative emissions and EF were related to yield scaled emissions.

The contribution of cattle urine and dung to nitrous oxide emissions: Quantification of country specific emission factors and implications for national inventories

Urine patches and dung pats from grazing livestock create hotspots for production and emission of the greenhouse gas, nitrous oxide (N₂O), and represent a large proportion of total N₂O emissions in many national agricultural greenhouse gas inventories. As such, there is much interest in developing country specific N₂O emission factors (EFs) for excretal nitrogen (EF_3, pasture, range and paddock) deposited during gazing. The aims of this study were to generate separate N₂O emissions data for cattle derived urine and dung, to provide an evidence base for the generation of a country specific EF for the UK from this nitrogen source. The experiments were also designed to determine the effects of site and timing of application on emissions, and the efficacy of the nitrification inhibitor, dicyandiamide (DCD) on N₂O losses. This co-ordinated set of 15 plot-scale, year-long field experiments using static chambers was conducted at five grassland sites, typical of the soil and climatic zones of grazed grassland in the UK. We show that the average urine and dung N₂O EFs were 0.69% and 0.19%, respectively, resulting in a combined excretal N₂O EF (EF₃), of 0.49%, which is <25% of the IPCC default EF₃ for excretal returns from grazing cattle. Regression analysis suggests that urine N₂O EFs were controlled more by composition than was the case for dung, whilst dung N₂O EFs were more related to soil and environmental factors. The urine N₂O EF was significantly greater from the site in SW England, and significantly greater from the early grazing season urine application than later applications. Dycandiamide reduced the N₂O EF from urine patches by an average of 46%. The significantly lower excretal EF₃ than the IPCC default has implications for the UK's national inventory and for subsequent carbon footprinting of UK ruminant livestock products.

Risk of pre-eclampsia in women taking metformin: a systematic review and meta-analysis

AIMS

To perform meta-analyses of studies evaluating the risk of pre-eclampsia in high-risk insulin-resistant women taking metformin prior to, or during pregnancy.

METHODS

A search was conducted of the Medline, EMBASE, Web of Science and Scopus databases. Both randomized controlled trials and prospective observational cohort studies of metformin treatment vs. placebo/control or insulin either prior to or during pregnancy were selected. The main outcome measure was the incidence of pre-eclampsia in each treatment group.

RESULTS

Overall, in five randomized controlled trials comparing metformin treatment (n = 611) with placebo/control (n = 609), no difference in the risk of pre-eclampsia was found [combined/pooled risk ratio (RR), 0.86 (95% CI 0.33-2.26); P = 0.76; I²  = 66%]. Meta-analysis of four cohort studies again showed no significant effect [RR, 1.21 (95% CI 0.56-2.61); P = 0.62; I²  = 30%]. A meta-analysis of eight randomized controlled trials comparing metformin (n = 838) with insulin (n = 836), however, showed a reduced risk of pre-eclampsia with metformin [RR, 0.68 (95% CI 0.48-0.95); P = 0.02; I²  = 0%]. No heterogeneity was present in the metformin vs. insulin analysis of randomized controlled trials, whereas high levels of heterogeneity were present in studies comparing metformin with placebo/control. Pre-eclampsia was a secondary outcome in most of the studies. The mean weight gain from time of enrolment to delivery was lower in the metformin group (P = 0.05, metformin vs. placebo; P = 0.004, metformin vs. insulin).

CONCLUSIONS

In studies randomizing pregnant women to glucose-lowering therapy, metformin was associated with lower gestational weight gain and a lower risk of pre-eclampsia compared with insulin.

Improving and disaggregating N2O emission factors for ruminant excreta on temperate pasture soils

Cattle excreta deposited on grazed grasslands are a major source of the greenhouse gas (GHG) nitrous oxide (N2O). Currently, many countries use the IPCC default emission factor (EF) of 2% to estimate excreta-derived N2O emissions. However, emissions can vary greatly depending on the type of excreta (dung or urine), soil type and timing of application. Therefore three experiments were conducted to quantify excreta-derived N2O emissions and their associated EFs, and to assess the effect of soil type, season of application and type of excreta on the magnitude of losses. Cattle dung, urine and artificial urine treatments were applied in spring, summer and autumn to three temperate grassland sites with varying soil and weather conditions. Nitrous oxide emissions were measured from the three experiments over 12months to generate annual N2O emission factors. The EFs from urine treated soil was greater (0.30-4.81% for real urine and 0.13-3.82% for synthetic urine) when compared with dung (-0.02-1.48%) treatments. Nitrous oxide emissions were driven by environmental conditions and could be predicted by rainfall and temperature before, and soil moisture deficit after application; highlighting the potential for a decision support tool to reduce N2O emissions by modifying grazing management based on these parameters. Emission factors varied seasonally with the highest EFs in autumn and were also dependent on soil type, with the lowest EFs observed from well-drained and the highest from imperfectly drained soil. The EFs averaged 0.31 and 1.18% for cattle dung and urine, respectively, both of which were considerably lower than the IPCC default value of 2%. These results support both lowering and disaggregating EFs by excreta type.

Reducing nitrous oxide emissions by changing N fertiliser use from calcium ammonium nitrate (CAN) to urea based formulations

The accelerating use of synthetic nitrogen (N) fertilisers, to meet the world's growing food demand, is the primary driver for increased atmospheric concentrations of nitrous oxide (N2O). The IPCC default emission factor (EF) for N2O from soils is 1% of the N applied, irrespective of its form. However, N2O emissions tend to be higher from nitrate-containing fertilisers e.g. calcium ammonium nitrate (CAN) compared to urea, particularly in regions, which have mild, wet climates and high organic matter soils. Urea can be an inefficient N source due to NH3 volatilisation, but nitrogen stabilisers (urease and nitrification inhibitors) can improve its efficacy. This study evaluated the impact of switching fertiliser formulation from calcium ammonium nitrate (CAN) to urea-based products, as a potential mitigation strategy to reduce N2O emissions at six temperate grassland sites on the island of Ireland. The surface applied formulations included CAN, urea and urea with the urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT) and/or the nitrification inhibitor dicyandiamide (DCD). Results showed that N2O emissions were significantly affected by fertiliser formulation, soil type and climatic conditions. The direct N2O emission factor (EF) from CAN averaged 1.49% overall sites, but was highly variable, ranging from 0.58% to 3.81. Amending urea with NBPT, to reduce ammonia volatilisation, resulted in an average EF of 0.40% (ranging from 0.21 to 0.69%)-compared to an average EF of 0.25% for urea (ranging from 0.1 to 0.49%), with both fertilisers significantly lower and less variable than CAN. Cumulative N2O emissions from urea amended with both NBPT and DCD were not significantly different from background levels. Switching from CAN to stabilised urea formulations was found to be an effective strategy to reduce N2O emissions, particularly in wet, temperate grassland.

The BH3-only protein BIM contributes to late-stage involution in the mouse mammary gland

After cessation of lactation, involution of the mouse mammary gland proceeds in two distinct phases, a reversible and an irreversible one, which leads to the death and removal of alveolar cells. Cell death is preceded by the loss of STAT5 activity, which abrogates cell differentiation and gain of STAT3 activity. Despite early observations implicating BCL2 (B cell lymphoma 2) family proteins in this process, recent evidence suggests that STAT3-controlled cathepsin activity is most critical for cell death at the early stage of involution. Somewhat surprisingly, this cell death associates with but does not depend on the activation of pro-apoptotic effector caspases. However, transgenic overexpression of BCL2, that blocks caspase activation, delays involution while conditional deletion of BclX accelerates this process, suggesting that BCL2 family proteins are needed for the effective execution of involution. Here, we report on the transcriptional induction of multiple pro-apoptotic BCL2 family proteins of the 'BH3-only' subgroup during involution and the rate-limiting role of BIM in this process. Loss of Bim delayed epithelial cell clearance during involution after forced weaning in mice, whereas the absence of related Bmf had minor and loss of Bad or Noxa no impact on this process. Consistent with a contribution of BCL2 family proteins to the second wave of cell death during involution, loss of Bim reduced the number of apoptotic cells in this irreversible phase. Notably, the expression changes observed within the BCL2 family did not depend on STAT3 signalling, in line with its initiating role early in the process, but rather appear to result from relief of repression by STAT5. Our findings support the existence of a signalling circuitry regulating the irreversible phase of involution in mice by engaging BH3-only protein-driven mitochondrial apoptosis.

Early graft loss after kidney transplantation: risk factors and consequences

Early graft loss (EGL) after kidney transplantation is a catastrophic outcome that is assumed to be more likely after the use of kidneys from suboptimal donors. We therefore examined its incidence, risk factors and consequences in our center in relation to different donor types. Of 801 recipients who received a kidney-only transplant from deceased donors, 50 (6.2%) suffered EGL within 30 days of transplantation. Significant risks factors for EGL were donation after circulatory death (DCD) (odds ratio [OR] 2.88; p = 0.006), expanded criteria donor (ECD) transplantation (OR 4.22; p = 0.010), donor age (OR 1.03; p = 0.044) and recipient past history of thrombosis (OR 4.91; p = 0.001). Recipients with EGL had 12.28 times increased risk of death within the first year, but long-term survival was worse for patients remaining on the waiting list. In comparison with patients on the waiting list but not transplanted, and with all patients on the waiting list, the risk of death after EGL decreased to baseline 4 and 23 months after transplantation, respectively. Our findings suggest that DCD and ECD transplantation are significant risk factors for EGL, which is a major risk factor for recipient death. However, long-term mortality is even greater for those remaining on the waiting list.

Adenosine A₁ receptors in mouse pontine reticular formation modulate nociception only in the presence of systemic leptin

Human obesity is associated with increased leptin levels and pain, but the specific brain regions and neurochemical mechanisms underlying this association remain poorly understood. This study used adult male C57BL/6J (B6, n=14) mice and leptin-deficient, obese B6.Cg-Lep(ob)/J (obese, n=10) mice to evaluate the hypothesis that nociception is altered by systemic leptin levels and by adenosine A₁ receptors in the pontine reticular formation. Nociception was quantified as paw withdrawal latency (PWL) in s after onset of a thermal stimulus. PWL was converted to percent maximum possible effect (%MPE). After obtaining baseline PWL measures, the pontine reticular formation was microinjected with saline (control), three concentrations of the adenosine A₁ receptor agonist N(6)-p-sulfophenyladenosine (SPA), or super-active mouse leptin receptor antagonist (SMLA) followed by SPA 15 min later, and PWL was again quantified. In obese, leptin-deficient mice, nociception was quantified before and during leptin replacement via subcutaneous osmotic pumps. SPA was administered into the pontine reticular formation of leptin-replaced mice and PWL testing was repeated. During baseline (before vehicle or SPA administration), PWL was significantly (p=0.0013) lower in leptin-replaced obese mice than in B6 mice. Microinjecting SPA into the pontine reticular formation of B6 mice caused a significant (p=0.0003) concentration-dependent increase in %MPE. SPA also significantly (p<0.05) increased %MPE in B6 mice and in leptin-replaced obese mice, but not in leptin-deficient obese mice. Microinjection of SMLA into the pontine reticular formation before SPA did not alter PWL. The results show for the first time that pontine reticular formation administration of the adenosine A₁ receptor agonist SPA produced antinociception only in the presence of systemic leptin. The concentration-response data support the interpretation that adenosine A₁ receptors localized to the pontine reticular formation significantly alter nociception.

Sarcoidosis, alveolar β-actin and pulmonary fibrosis

BACKGROUND

Sarcoidosis is a multisystem granulomatous disease of unknown aetiology. Proteins present within the alveolar space early in sarcoidosis disease may provide an insight into novel mechanisms for the development of fibrotic disease and in particular pulmonary fibrosis.

METHODS

A modified two-dimensional difference gel electrophoresis protocol was applied to the human bronchoalveolar lavage fluid (hBALF) of four patients with non-persistent pulmonary interstitial disease at 4-year follow-up (defined as mild disease) and four patients who developed pulmonary interstitial disease at 4-year follow-up (defined as severe disease). The protein β-actin was identified by LC-MS/MS from a preparative gel and found to be significantly elevated in early lavages from the severe disease group. To look at the potential pro-fibrotic effects of this protein, primary human pulmonary fibroblasts (CCD-19Lu) were treated with recombinant β-actin following which qPCR and ELISA assays were used to measure any effects.

RESULTS

We found that β-actin levels were significantly elevated in early hBALF samples in patients who subsequently developed severe disease when compared to the mild group. Treating primary human pulmonary fibroblasts with recombinant β-actin led to enhanced gene expression of the pro-fibrotic markers alpha smooth muscle actin and collagen 1 as well as the increased secretion of interleukin-13 and metalloproteinases 3 and 9.

CONCLUSION

Free β-actin within the lungs of sarcoidosis patients potentially may contribute to disease pathogenesis particularly in the context of abnormal remodelling and the development of pulmonary fibrosis.

The changing face of donation in the UK: kidney donation after circulatory death

Affiliated to the Association of Surgeons in Training and the British Transplantation Society, the Carrel Club is the transplant trainee surgical society. The Carrel Club held a joint meeting with the Chapter of Transplant Surgeons, a subsidiary organisation of the British Transplantation Society, at the Manchester Hilton Hotel on 31 January and 1 February 2013. As part of the meeting, ten abstracts were presented. A selection is printed below. The winner of the Best Presentation award was Mr Mownah.

Dynamics of critical source areas: does connectivity explain chemistry?

Critical source area approaches to catchment management are increasingly being recognised as effective tools to mitigate sediment and nutrient transfers. These approaches often assume hydrological connectivity as a driver for environmental risk, however this assumption has rarely been tested. Using high resolution monitoring, 14 rainfall events of contrasting intensity were examined in detail for spatial and temporal dynamics of overland flow generation at a hydrologically isolated grassland hillslope in Co. Down, Northern Ireland. Interactions between overland flow connectivity and nutrient transfers were studied to test the critical source area hypothesis. While total and soluble phosphorus loads were found to be representative of the size of the overland flow contributing area (P=<0.05), the dynamics of concentrations throughout storm hydrographs were found to be complex and storm dependant. Near linear relationships were observed between the contributing area and total overland flow volumes (R(2)=0.86). Export coefficients (kg ha(-1)) calculated using plot size were found to under estimate annual losses of total phosphorus by a factor of 17, when compared to those calculated using the contributing area. This study shows that current critical source area definitions for implementing mitigation measures may be overlooking the importance of storm characteristics in determining nutrient transfers and hence may be insufficient in determining catchment scale risk.

Use of complementary and alternative medicine in recurrent vulvovaginal candidiasis--results of a practitioner survey

BACKGROUND

The mainstream long term management of recurrent vulvovaginal candidiasis (RVVC) often results in poor outcomes. It is expensive and unacceptable for many women who therefore have incorporated complementary and alternative medicine (CAM) into their personal care plan.

OBJECTIVE

To ascertain clinicians' knowledge of CAM and their recommendations for the use of CAM and non-pharmacological management in women with RVVC.

DESIGN AND SETTING

Anonymous, single page, self completed survey using convenience sampling at a vulval disorders meeting in New South Wales, Australia in 2009.

PARTICIPANTS

Sixty six health professionals (medical practitioners, dermatologists, nurses and allied health professionals).

RESULTS

Most clinicians reported asking about their patients' use of CAM and non-pharmacological management of RVVC, although only around half reported recommending it. CAM management included lactobacillus, oral and vaginal yoghurt, vinegar, garlic, Chinese medicine and tea-tree oil. Non-pharmacological management included dietary changes and use of cotton undergarments. Lactobacillus was the most commonly recommended CAM.

CONCLUSION

CAM is popular with patients and many clinicians actively recommend its use in RVVC despite limited supporting evidence. Further research in the area of CAM and RVVC is long overdue.

Biomimetic collagen scaffolds with anisotropic pore architecture

Sponge-like matrices with a specific three-dimensional structural design resembling the actual extracellular matrix of a particular tissue show significant potential for the regeneration and repair of a broad range of damaged anisotropic tissues. The manipulation of the structure of collagen scaffolds using a freeze-drying technique was explored in this work as an intrinsically biocompatible way of tailoring the inner architecture of the scaffold. The research focused on the influence of temperature gradients, imposed during the phase of crystallisation of collagen suspensions, upon the degree of anisotropy in the microstructures of the scaffolds produced. Moulding technology was employed to achieve differences in heat transfer rates during the freezing processes. For this purpose various moulds with different configurations were developed with a view to producing uniaxial and multi-directional temperature gradients across the sample during this process. Scanning electron microscopy analysis of different cross-sections (longitudinal and horizontal) of scaffolds revealed that highly aligned matrices with axially directed pore architectures were obtained where single unidirectional temperature gradients were induced. Altering the freezing conditions by the introduction of multiple temperature gradients allowed collagen scaffolds to be produced with complex pore orientations, and anisotropy in pore size and alignment.

Identification of a methylation hotspot in the death receptor Fas/CD95 in bladder cancer

We characterized Fas immunoreactivity, functionality and its role in the response to mitomycin-C (MMC) chemotherapy in vitro in cell lines and in vivo in bladder washings from 23 transitional cell carcinoma of the bladder (TCCB) patients, harvested prior to and during MMC intravesical treatment. Having established the importance of functional Fas, we investigated the methylation and exon 9 mutation as mechanisms of Fas silencing in TCCB. For the first time, we report p53 up-regulation in 9/14 and Fas up-regulation in 7/9 TCCB patients during intravesical MMC treatment. Fas immunoreactivity was strong in the TCCB cell line T24 and in 17/20 (85%) tumor samples from patients with advanced TCCB. T24 and HT1376 cells were resistant to MMC and recombinant Fas ligand, whilst RT4 cells were responsive to Fas ligand and MMC. Using RT4 cells as a model, siRNA targeting p53 significantly reduced MMC-induced p53 and Fas up-regulation and stable DN-FADD transfection decreased MMC-induced apoptosis, suggesting that functional Fas enhances chemotherapy responses in a p53-dependent manner. In HT1376 cells, 5-aza-2-deoxycytidine (12 µM) induced Fas immunoreactivity and reversed methylation at CpG site -548 within the Fas promoter. This site was methylated in 13/24 (54%) TCCB patient samples assessed using Methylation-Specific Polymerase Chain Reaction. There was no methylation at either the p53 enhancer region within the first intron or at the SP-1 binding region in the promoter and no mutation within exon 9 in tumor DNA extracted from 38 patients. Methylation at CpG site -548 is a potential target for demethylating drugs.

Getting to the heart of cardiac remodeling; how collagen subtypes may contribute to phenotype

The objective of this study was to investigate the nature and biomechanical properties of collagen fibers within the human myocardium. Targeting cardiac interstitial abnormalities will likely become a major focus of future preventative strategies with regard to the management of cardiac dysfunction. Current knowledge regarding the component structures of myocardial collagen networks is limited, further delineation of which will require application of more innovative technologies. We applied a novel methodology involving combined confocal laser scanning and atomic force microscopy to investigate myocardial collagen within ex-vivo right atrial tissue from 10 patients undergoing elective coronary bypass surgery. Immuno-fluorescent co-staining revealed discrete collagen I and III fibers. During single fiber deformation, overall median values of stiffness recorded in collagen III were 37±16% lower than in collagen I [p<0.001]. On fiber retraction, collagen I exhibited greater degrees of elastic recoil [p<0.001; relative percentage increase in elastic recoil 7±3%] and less energy dissipation than collagen III [p<0.001; relative percentage increase in work recovered 7±2%]. In atrial biopsies taken from patients in permanent atrial fibrillation (n=5) versus sinus rhythm (n=5), stiffness of both collagen fiber subtypes was augmented (p<0.008). Myocardial fibrillar collagen fibers organize in a discrete manner and possess distinct biomechanical differences; specifically, collagen I fibers exhibit relatively higher stiffness, contrasting with higher susceptibility to plastic deformation and less energy efficiency on deformation with collagen III fibers. Augmented stiffness of both collagen fiber subtypes in tissue samples from patients with atrial fibrillation compared to those in sinus rhythm are consistent with recent published findings of increased collagen cross-linking in this setting.

Constitutive activation of JAK2 in mammary epithelium elevates Stat5 signalling, promotes alveologenesis and resistance to cell death, and contributes to tumourigenesis

Signalling through the janus kinase (JAK)/signal transducer and activator of transcription (Stat) pathway is required at different stages of mammary gland development, and this pathway is frequently hyper-activated in cancer, including tumours of the breast. Stats 3, 5 and 6 have important roles in the differentiation and survival of mammary alveolar cells, but somewhat paradoxically, both Stat3 and 5 can have oncogenic activity in the mammary gland. Constitutive activation of JAK2 could be anticipated to result in hyper-activation of Stats 1, 3, 5 and 6 with concomitant cell transformation, although the outcome is difficult to envisage, particularly since Stats 3 and 5 play opposing roles in normal mammary gland development. Here, we show that expression of a constitutively active JAK2 mutant, JAK2 V617F, leads to hyper-activation of Stat5 in mammary epithelial cells (MECs), and transgenic mice expressing JAK2 V617F specifically in the mammary gland exhibit accelerated alveologenesis during pregnancy and delayed post-lactational regression. Overexpressing JAK2 V617F in MECs in vitro results in elevated proliferation and resistance to cell death. Furthermore, constitutively active JAK2 enhances anchorage-independent cell growth in the presence of a co-operating oncogene and accelerates tumourigenesis in a xenograft model. Taken together, our results provide insights into signalling downstream of constitutively active JAK2 and could be important for understanding the molecular mechanisms of breast tumourigenesis.

Effect of varying the phosphorus content of dairy cow diets on losses of phosphorus in overland flow following surface applications of manure

The increasing use of concentrate feedstuffs within Northern Ireland dairy systems has resulted in significant farm gate phosphorus (P) surpluses, and these have contributed to increased soil P levels and risk of P loss to overland flow. However, the P content of feed concentrates can be lowered without compromising animal performance. This study focuses on P losses from grassland and evaluates how adjusting the P content of manure impacts on the P composition and concentration in overland flow. Dairy cows were offered diets containing 5.3 to 3.0 g P kg(-1) dry matter (DM) and produced manures with a range of P contents. Manure was applied at a rate of 50 m3 ha(-1) to 0.5-m2 grassland plots, and simulated rainfall (40 mm h(-1)) was applied repeatedly 2, 9, 28, and 49 d after during the summer, winter, and spring. Decreasing the P content in the diet, from the highest to the lowest P treatment (43%), produced a proportionately greater reduction in manure TP content (63%), but reductions were not exclusively in the water-soluble fraction. Following surface applications of manure, P concentrations in overland flow increased in all seasons (P < or = 0.001), while the greatest impact of varying the manure P content was most evident during the first simulated overland flow event. When diet P content was reduced from 5.4 to 3.0 g P kg(-1) DM, a statistically significant reduction in runoff P concentration was observed in all seasons. Elevated P concentrations in overland flow were observed for 28 d in spring and 9 d in summer and winter. The large drop in P concentrations between simulated rainfall events on Day 2 and Day 9 suggests that increasing the time interval between manure application and the generation of overland flow has a greater impact on P losses than does varying the dietary P content.

Evidence for the production of NO and N2O in two contrasting subsoils following the addition of synthetic cattle urine

Nitrogenous materials can be transferred out of the topsoil, either vertically to a greater depth, or in lateral pathways to surface waters, and they may also become transformed, with the potential of generating environmentally active agents. We measured the production of NO and N(2)O in two contrasting subsoils (70 to 90 cm): one poorly drained and the other freely drained and compared this with the topsoil (0 to 20 cm) of the corresponding soils. The soils were incubated aerobically in jars with subtreatments of either synthetic cattle urine or deionised water and sampled at intervals up to 34 days. (15)N-NO(3)(-) was used to determine the processes responsible for NO and N(2)O production. The headspace was analysed for the concentrations of N(2)O, NO and CO(2) and (15)N enrichment of N(2)O. The soil samples were extracted and analysed for NO(2)(-), NO(3)(-) and NH(4)(+), and the (15)N enrichment of the extracts was measured after conversion into N(2)O and N(2). The study demonstrated the potential for NO, N(2)O and NO(2)(-) to be generated from subsoils in laboratory incubations. Differences in these N dynamics occurred due to subsoil drainage class. In the freely drained subsoil the rates of NO and NO(2)(-) production were higher than those observed for the corresponding topsoil, with mean maximum production rates of 3.5 microg NO(2)(-)-N g(-1) dry soil on day 16 and 0.12 microg NO-N g(-1) dry soil on day 31. The calculated total losses of N(2)O-N as percentages of the applied synthetic urine N were 0.37% (freely drained subsoil), 0.24% (poorly drained subsoil), 0.43% (freely drained topsoil) and 2.09% (poorly drained topsoil). The calculated total losses of NO-N as percentages of the applied synthetic urine N were 1.53% (freely drained subsoil), 0.02% (poorly drained subsoil), 0.25% (freely drained topsoil) and 0.08% (poorly drained topsoil).

Acute cytomegalovirus cholecystitis following renal transplantation

Solid organ transplant recipients are at risk of infection from cytomegalovirus (CMV). A wide range of disease is associated with CMV infection and we report two cases of CMV cholecystitis in patients following renal transplantation. Both patients presented with severe hemorrhagic cholecystitis, which required immediate resuscitation and emergency cholecystectomy. The diagnosis of CMV infection was confirmed in both cases using CMV-specific staining of the gallbladder. The diagnosis of CMV cholecystitis must be considered in all patients with upper abdominal pain after renal transplantation.

Transitory renal failure following rapid administration of a relatively large amount of hematin in a patient with acute intermittent porphyria in clinical remission

Transitory renal failure occurred in a patient with acute intermittent porphyria in clinical remission following i.v. administration of 1 000 mg hematin. The clinical and biochemical picture suggested "acute tubular necrosis", which was followed by a prompt and complete return of renal function without any late sequelae. The renal failure is thought to have resulted from the presence of circulating free hematin, formed as a result of rapid administration of such a relatively large amount. Such a complication has not occurred in patients given hematin for acute porphyric relapse, in whom much smaller amounts have been infused.

Immune cell regulators in mouse mammary development and involution

Dramatic changes in cell composition and function occur in the mammary gland during a pregnancy-lactation-involution cycle. We investigated the transcriptional changes associated with these biological events by using microarray analysis and identified the critical genes involved by using genetically modified mice. Two surprising findings arose from these studies. First, the microarray data showed that postlactational regression was associated with an acute phase inflammatory response, in addition to cell death. Conditional deletion of signal transducer and activator of transcription (Stat)3 or the nuclear factor-kappaB regulatory kinase inhibitor of kappa B kinase beta resulted in a failure of cell death induction during involution, an indication that these signaling pathways are essential mediators of the involution process. Both Stat3 and nuclear factor-kappaB have been shown to regulate acute phase gene expression in addition to apoptosis regulators. Four distinct transcriptional profiles are present in the first 4 d of involution, whereas there are 3 in lactation. At the peak of lactation (i.e., d 10 in mouse), more than 400 genes reach their maximum expression before declining dramatically in the first 12 h of involution. A reciprocal pattern was observed for more than 500 genes that were specifically upregulated within the first 12 h of forced involution. We are now investigating the role of a subset of these genes in involution. We also uncovered a role for genes normally associated with immune cell signaling in the differentiation of luminal mammary epithelial cells during pregnancy. Genetic deletion of the transcription factor Stat6 resulted in delayed development during pregnancy, and this phenotype was recapitulated in mammary tissue from IL-4 and IL-13 doubly deficient mice. Furthermore, we showed that mammary epithelial cells secrete T-cell regulatory cytokines. T-helper type 1 cytokines, such as interferon-gamma and IL-12a, are secreted by undifferentiated mammary epithelial cells, whereas T-helper type 2 cytokines, including IL-4 and IL-13, are secreted by differentiated cells. This unexpected finding demonstrates a role for immune cell signaling in mammary epithelial cell fate and function.

The Stat family of transcription factors have diverse roles in mammary gland development

The Stat family of transcription factors have diverse roles in mammary gland development. Genetic studies in mice have revealed an essential requirement for Stat5a in development of secretory alveolar cells during pregnancy while Stat6, which is normally associated with differentiation of T helper cells, is important in the commitment of luminal cells to this alveolar lineage. In contrast, Stat3 is specifically activated at the initiation of post-lactational regression when it has an essential function in the regulation of cell death and tissue remodelling. Stat1 and Stat4 have been shown to be regulated during a mammary developmental cycle although whether they have specific, non-redundant roles is not clear. Thus, the adult mammary gland is somewhat unusual in that it is a tissue where different Stats are sequentially activated to orchestrate the processes of functional differentiation, cell death and tissue remodelling.

Increase in phosphorus losses from grassland in response to Olsen-P accumulation

The Olsen-P status of grazed grassland (Lolium perenne L.) swards in Northern Ireland was increased over a 5-yr period (March 2000 to February 2005) by applying different rates of P fertilizer (0, 10, 20, 40, or 80 kg P ha(-1) yr(-1)) to assess the relationship between soil P status and P losses in land drainage water and overland flow. Plots (0.2 ha) were hydrologically isolated and artificially drained to v-notch weirs, with flow proportional monitoring of drainage water and overland flow. Annually, the collectors for overland flow intercepted between 11 and 35% of the surplus rainfall. Single flow events accounted for up to 52% of the annual dissolved reactive phosphorus (DRP) load. The Olsen-P status of the soil influenced DRP and total phosphorus (TP) concentrations in land drainage water and overland flow. Annual TP loss was highly variable and ranged from 0.19 to 1.55 kg P ha(-1) yr(-1) for the plot receiving no P fertilizer and from 0.35 to 2.94 kg P ha(-1) yr(-1) for the plot receiving 80 kg P ha(-1) yr(-1). Despite the Olsen-P status in the soils ranging from 22 to 99 mg P kg(-1), after 5 yr of fertilizer P applications it was difficult to identify a clear Olsen-P concentration at which P losses increased. Any relationship was confounded by annual variability of hydrologic events and flows and by hydrologic differences between plots. Withholding P fertilizer for over 5 yr was not long enough to lower P losses or to have an adverse effect on herbage P concentrations.

Sleep and GABA levels in the oral part of rat pontine reticular formation are decreased by local and systemic administration of morphine

Morphine, a mu-opioid receptor agonist, is a commonly prescribed treatment for pain. Although highly efficacious, morphine has many unwanted side effects including disruption of sleep and obtundation of wakefulness. One mechanism by which morphine alters sleep and wakefulness may be by modulating GABAergic signaling in brain regions regulating arousal, including the pontine reticular nucleus, oral part (PnO). This study used in vivo microdialysis in unanesthetized Sprague-Dawley rat to test the hypothesis that mu-opioid receptors modulate PnO GABA levels. Validation of the high performance liquid chromatographic technique used to quantify GABA was obtained by dialyzing the PnO (n=4 rats) with the GABA reuptake inhibitor nipecotic acid (500 microM). Nipecotic acid caused a 185+/-20% increase in PnO GABA levels, confirming chromatographic detection of GABA and demonstrating the existence of functional GABA transporters in rat PnO. Morphine caused a concentration-dependent decrease in PnO GABA levels (n=25 rats). Coadministration of morphine (100 microM) with naloxone (1 microM), a mu-opioid receptor antagonist, blocked the morphine-induced decrease in PnO GABA levels (n=5 rats). These results show for the first time that mu-opioid receptors in rat PnO modulate GABA levels. A second group of rats (n=6) was used to test the hypothesis that systemically administered morphine also decreases PnO GABA levels. I.v. morphine caused a significant (P<0.05) decrease (19%) in PnO GABA levels relative to control i.v. infusions of saline. Finally, microinjections followed by 2 h recordings of electroencephalogram and electromyogram tested the hypothesis that PnO morphine administration disrupts sleep (n=8 rats). Morphine significantly (P<0.05) increased the percent of time spent in wakefulness (65%) and significantly (P<0.05) decreased the percent of rapid eye movement (REM) sleep (-53%) and non-REM sleep (-69%). The neurochemical and behavioral data suggest that morphine may disrupt sleep, at least in part, by decreasing GABAergic transmission in the PnO.