Renal hemofiltration prevents metabolic acidosis and reduces inflammation during normothermic machine perfusion of the vascularized composite allograft—A preclinical study

From Wiley via Jisc Publications RouterHistory: received 2021-05-17, rev-recd 2021-09-16, accepted 2021-09-24, pub-electronic 2021-11-26Article version: VoRPublication status: PublishedAbstract: Introduction: Recent experimental evidence suggests normothermic machine perfusion of the vascularized composite allograft results in improved preservation compared to static cold storage, with less reperfusion injury in the immediate post‐operative period. However, metabolic acidosis is a common feature of vascularized composite allograft perfusion, primarily due to the inability to process metabolic by‐products. We evaluated the impact of combined limb‐kidney perfusion on markers of metabolic acidosis and inflammation in a porcine model. Methods: Ten paired pig forelimbs were used for this study, grouped as either limb‐only (LO, n = 5) perfusion, or limb‐kidney (LK, n = 5) perfusion. Infrared thermal imaging was used to determine homogeneity of perfusion. Lactate, bicarbonate, base, pH, and electrolytes, along with an inflammatory profile generated via the quantification of cytokines and cell‐free DNA in the perfusate were recorded. Results: The addition of a kidney to a limb perfusion circuit resulted in the rapid stabilization of lactate, bicarbonate, base, and pH. Conversely, the LO circuit became progressively acidotic, correlating in a significant increase in pro‐inflammatory cytokines. Global perfusion across the limb was more homogenous with LK compared to LO. Conclusion: The addition of a kidney during limb perfusion results in significant improvements in perfusate biochemistry, with no evidence of metabolic acidosis

Herbal remedy clinical trials in the media: a comparison with the coverage of conventional pharmaceuticals

<p>Abstract</p> <p>Background</p> <p>This study systematically compares newspaper coverage of clinical trials for herbal remedies, a popular type of complementary and alternative medicine, with clinical trials for pharmaceuticals using a comparative content analysis. This is a timely inquiry given the recognized importance of the popular press as a source of health information, the complex and significant role of complementary and alternative medicine in individual health-care decisions, and the trend toward evidence-based research for some complementary and alternative medical therapies. We searched PubMed for clinical trials, Lexis/Nexis for newspaper articles in the UK, US, Australia/New Zealand, and Factiva for Canadian newspaper articles from 1995 to 2005. We used a coding frame to analyze and compare 48 pharmaceutical and 57 herbal remedy clinical trials as well as 201 pharmaceutical and 352 herbal remedy newspaper articles.</p> <p>Results</p> <p>Herbal remedy clinical trials had similar Jadad scores to pharmaceutical trials but were significantly smaller and of shorter duration. The trials were mostly studies from Western countries and published in high-ranking journals. The majority of pharmaceutical (64%) and herbal remedy (53%) clinical trials had private sector funding involvement. A minority declared further author conflicts of interest. Newspaper coverage of herbal remedy clinical trials was more negative than for pharmaceutical trials; a result only partly explained by the greater proportion of herbal remedy clinical trials reporting negative results (<it>P </it>= 0.0201; <it>χ</it>²= 7.8129; degrees of freedom = 2). Errors of omission were common in newspaper coverage, with little reporting of dose, sample size, location, and duration of the trial, methods, trial funding, and conflicts of interest. There was an under-reporting of risks, especially for herbal remedies.</p> <p>Conclusion</p> <p>Our finding of negative coverage of herbal remedy trials is contrary to the positive trends in most published research based primarily on anecdotal accounts. Our results highlight how media coverage is not providing the public with the information necessary to make informed decisions about medical treatments. Most concerning is the lack of disclosure of trial funding and conflicts of interest that could influence the outcome or reporting of trial results. This lack of reporting may impact the medical research community, which has the most to lose by way of public trust and respect.</p

Discovery of novel heart rate-associated loci using the Exome Chip

Resting heart rate is a heritable trait, and an increase in heart rate is associated with increased mortality risk. Genome-wide association study analyses have found loci associated with resting heart rate, at the time of our study these loci explained 0.9% of the variation. This study aims to discover new genetic loci associated with heart rate from Exome Chip meta-analyses. Heart rate was measured from either elecrtrocardiograms or pulse recordings. We meta-analysed heart rate association results from 104 452 European-ancestry individuals from 30 cohorts, genotyped using the Exome Chip. Twenty-four variants were selected for follow-up in an independent dataset (UK Biobank, N = 134 251). Conditional and gene-based testing was undertaken, and variants were investigated with bioinformatics methods. We discovered five novel heart rate loci, and one new independent low-frequency non-synonymous variant in an established heart rate locus (KIAA1755). Lead variants in four of the novel loci are non-synonymous variants in the genes C10orf71, DALDR3, TESK2 and SEC31B. The variant at SEC31B is significantly associated with SEC31B expression in heart and tibial nerve tissue. Further candidate genes were detected from long-range regulatory chromatin interactions in heart tissue (SCD, SLF2 and MAPK8). We observed significant enrichment in DNase I hypersensitive sites in fetal heart and lung. Moreover, enrichment was seen for the first time in human neuronal progenitor cells (derived from embryonic stem cells) and fetal muscle samples by including our novel variants. Our findings advance the knowledge of the genetic architecture of heart rate, and indicate new candidate genes for follow-up functional studies

Abstracts from the NIHR INVOLVE Conference 2017

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Adherence to Mediterranean and low-fat diets among heart and lung transplant recipients: a randomized feasibility study

Abstract Background Heart and lung transplant recipients are at a substantially increased risk of cardiovascular disease (CVD). Since both low-fat and Mediterranean diets can reduce CVD in immunocompetent people at high risk, we assessed adherence among thoracic transplant recipients allocated to one or other of these diets for 12 months. Methods Forty-one transplant recipients (20 heart; 21 lung) randomized to a Mediterranean or a low-fat diet for 12 months received diet-specific education at baseline. Adherence was primarily assessed by questionnaire: 14-point Mediterranean diet (score 0–14) and 9-point low-fat diet (score 0–16) respectively, high scores indicating greater adherence. Median scores at baseline, 6 months, 12 months, and 6-weeks post-intervention were compared by dietary group. We further assessed changes in weight, body mass index (BMI) and serum triglycerides from baseline to 12 months as an additional indicator of adherence. Results In those randomized to a Mediterranean diet, median scores increased from 4 (range 1–9) at baseline, to 10 (range 6–14) at 6-months and were maintained at 12 months, and also at 6-weeks post-intervention (median 10, range 6–14). Body weight, BMI and serum triglycerides decreased over the 12-month intervention period (mean weight − 1.8 kg, BMI –0.5 kg/m2, triglycerides − 0.17 mmol/L). In the low-fat diet group, median scores were 11 (range 9–14) at baseline; slightly increased to 12 (range 9–16) at 6 months, and maintained at 12 months and 6 weeks post-intervention (median 12, range 8–15). Mean changes in weight, BMI and triglycerides were − 0.2 kg, 0.0 kg/m2 and − 0.44 mmol/L, respectively. Conclusions Thoracic transplant recipients adhered to Mediterranean and low-fat dietary interventions. The change from baseline eating habits was notable at 6 months; and this change was maintained at 12 months and 6 weeks post-intervention in both Mediterranean diet and low-fat diet groups. Dietary interventions based on comprehensive, well-supported education sessions targeted to both patients and their family members are crucial to success. Such nutritional strategies can help in the management of their substantial CVD risk. Trial registration The IRAS trial registry (ISRCTN63500150). Date of registration 27 July 2016. Retrospectively registered

Developing an Injury-Free 15 Hour Preservation Protocol of Donor Porcine Kidneys Using Normothermic Machine Perfusion

Normothermic machine perfusion (NMP) offers a superior alternative to hypothermic preservation but is currently time limited. Extending this time could electivise transplantation and enable physiologic assessments of functionality. Porcine kidneys were retrieved, stored on ice for 3.5 hours before being placed onto a NMP circuit for 12 hours. Hemodynamics, biochemistry, and urine output were assessed. After 12 hours, kidneys were scored using the clinical assessment score. Biopsies were collected for histological assessment. Kidneys demonstrated continual improvements in hemodynamics. Perfusate sodium concentrations remained within physiologic parameters. Sodium bicarbonate increased over-time with corresponding decreases in lactate, demonstrating active renal gluconeogenesis and Cori cycle processes. Urine production began immediately and was sustained, indicating renal functionality. Under the clinical perfusion assessment score, all kidneys received a score of 1 and would be considered suitable for transplantation. Histological assessment revealed kidneys were injury free. Our NMP protocol safely preserves kidneys for over 15 hours. Successful perfusion was achieved with stable hemodynamics and biochemistry, with maintained urination. Importantly, kidneys remained in optimal health, with no evidence of injury. This may enable electivisation of transplantation, while reducing hypothermic injury.</p

Renal haemofiltration prevents metabolic acidosis and reduces inflammation during normothermic machine perfusion of the vascularised composite allograft - a preclinical study.

INTRODUCTION Recent experimental evidence suggests normothermic machine perfusion of the vascularised composite allograft (VCA) results in improved preservation compared to static cold storage, with less reperfusion injury in the immediate post-operative period. However, metabolic acidosis is a common feature of VCA perfusion, primarily due to the inability to process metabolic by-products. We evaluated the impact of combined limb-kidney perfusion on markers of metabolic acidosis and inflammation in a porcine model. METHODS Ten paired pig forelimbs were used for this study, grouped as either limb-only (LO, n=5) perfusion, or limb-kidney (LK n=5) perfusion. Infrared thermal imaging was used to determine homogeneity of perfusion. Lactate, bicarbonate, base, pH, and electrolytes, along with an inflammatory profile generated via the quantification of cytokines and cell-free DNA in the perfusate were recorded. RESULTS The addition of a kidney to a limb perfusion circuit resulted in the rapid stabilisation of lactate, bicarbonate, base and pH. Conversely, the LO circuit became progressively acidotic, correlating in a significant increase in pro-inflammatory cytokines. Global perfusion across the limb was more homogenous with LK compared to LO. CONCLUSION The addition of a kidney during limb perfusion results in significant improvements in perfusate biochemistry, with no evidence of metabolic acidosis