Publications by authors named "Nader Abraham"

Normothermic machine perfusion (NMP) facilitates utilization of marginal liver allografts. It remains unknown whether clinical benefits offset additional costs in the real-world setting. We performed a comparison of outcomes and hospitalization costs for donor livers preserved by NMP versus static cold storage (SCS) at a high-volume center.

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  • Natural killer (NK) cells play a crucial role in managing both viral infections and immune responses during kidney transplants in children, as shown in a study using data from the CTOTC project.
  • The study analyzed NK cell phenotypes in 98 pediatric kidney transplant patients and found specific NK cell traits linked to either viral infections or alloimmune events, such as acute rejection.
  • These findings suggest that understanding NK cell profiles could help distinguish between risk factors for infections versus those for immune responses after transplantation.
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Background: The clinical success of liver transplantation has led to increased demand, requiring further expansion of the donor pool. Therapeutic interventions to optimize organs from donation after circulatory death (DCD) have significant potential to mitigate the organ shortage. Dysfunction in DCD liver grafts is mediated by microvascular thrombosis during the warm ischemic period, and strategies that reduce this thrombotic burden may improve graft function.

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Background: Ex vivo kidney perfusion is an evolving platform that demonstrates promise in preserving and rehabilitating the kidney grafts. Despite this, there is little consensus on the optimal perfusion conditions. Hypothermic perfusion offers limited functional assessment, whereas normothermic perfusion requires a more complex mechanical system and perfusate.

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Objective: Adeno-associated virus is a clinically used gene therapy vector but has not been studied in lung transplantation. We sought to determine the efficacy of adeno-associated virus delivery during static cold storage via the airway versus the pulmonary artery before lung transplantation in a rodent model.

Methods: Lewis rat lung grafts were treated with a dose of 8e8 or 4e9 viral genome/μL recombinant adeno-associated virus subtype-9 vectors containing firefly luciferase genomes administered via the pulmonary artery or airway during cold storage.

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  • Intestinal transplantation (IT) is considered the last resort for treating intestinal failure, with static cold storage (CS) being the traditional method for preserving donor organs, although it leads to harmful ischemia-reperfusion injury (IRI).
  • A new method called normothermic machine perfusion (NMP) is hypothesized to cause less damage and better protect the intestines’ ability to regenerate when compared to CS.
  • Experiments showed that intestines preserved using NMP had lower tissue damage, higher stem cell viability, and increased survivor rates after transplant, suggesting that NMP could enhance recovery and regeneration of transplanted intestines.
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Sterile inflammation is the immune response to damage-associated molecular patterns (DAMPs) released during cell death in the absence of foreign pathogens. In the setting of solid organ transplantation, ischemia-reperfusion injury results in mitochondria-mediated production of reactive oxygen and nitrogen species that are a major cause of uncontrolled cell death and release of various DAMPs from the graft tissue. When properly regulated, the immune response initiated by DAMP-sensing serves as means of damage control and is necessary for initiation of recovery pathways and re-establishment of homeostasis.

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  • This study compares two methods of preserving donor livers for transplantation: traditional static cold storage (SCS) and normothermic machine perfusion (NMP) which keeps the organs at body temperature.
  • The research involved 383 donor livers from various US transplant centers, and while there was no significant difference in early allograft dysfunction rates overall, NMP showed better outcomes for higher-risk donors, particularly in cases of organ donation after circulatory death.
  • The conclusion suggests that while NMP may not lower early liver injury rates universally, it is safe and potentially more beneficial for marginal donor livers.
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Introduction: Recombinant adeno-associated virus (rAAV) is a novel strategy used clinically for gene delivery, but has not been characterized in the context of organ transplantation. We sought to determine the efficacy of rAAV-mediated gene delivery during static cold storage (SCS) prior to liver transplantation.

Methods: A triple-plasmid transfection protocol was used to produce rAAV subtype-9 vectors containing firefly luciferase genomes in HEK293 cells.

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Organ shortages and an expanding waitlist have led to increased utilization of marginal organs. All donor organs are subject to varying degrees of IRI during the transplant process. Extended criteria organs, including those from older donors and organs donated after circulatory death are especially vulnerable to ischemia-reperfusion injury (IRI).

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Unlabelled: Successful intestinal transplantation is currently hindered by graft injury that occurs during procurement and storage, which contributes to postoperative sepsis and allograft rejection. Improved graft preservation may expand transplantable graft numbers and enhance posttransplant outcomes. Superior transplant outcomes have recently been demonstrated in clinical trials using machine perfusion to preserve the liver.

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Danon disease is a lethal X-linked genetic syndrome resulting from radical mutations in the LAMP2 gene. LAMP2 protein deficiency results in defective lysosomal function, autophagy arrest and a multisystem disorder primarily involving the heart, skeletal muscle and the central nervous system. Cardiomyopathy is the main cause of morbidity and mortality.

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  • * Novel strategies, such as gene therapy, are being explored to improve graft survival by targeting specific genetic pathways involved in lung injury and rejection.
  • * Recent advancements include FDA-approved AAV-based gene therapies and the use of normothermic ex vivo machine perfusion, which helps keep lungs viable during storage and may enhance gene therapy applications.
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Background: Subnormothermic machine perfusion (SNMP) of liver grafts is currently less clinically developed than normothermic and hypothermic approaches, but may have logistical advantages. At intermediate temperatures, the oxygen demand of the graft is low enough to be satisfied with an acellular perfusate, obviating the need for oxygen carrying molecules. This intermediate metabolic rate, however, is sufficient to support the production of bile, which is emerging as an important indicator of graft injury and viability.

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Liver transplantation offers excellent outcomes for patients with HCC. For those who initially present within the Milan criteria, bridging therapy is essential to control disease while awaiting liver transplant. For those who present beyond the Milan criteria, a liver transplant may still be considered following successful downstaging.

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Normothermic machine perfusion (NMP) provides clinicians an opportunity to assess marginal livers before transplantation. However, objective criteria and point-of-care (POC) biomarkers to predict risk and guide decision making are lacking. In this investigation, we characterized trends in POC biomarkers during NMP and compared primate donation after circulatory death (DCD) livers with short and prolonged warm ischemic injury.

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Obesity-mediated metabolic syndrome remains the leading cause of death worldwide. Among many potential targets for pharmacological intervention, a promising strategy involves the heme oxygenase (HO) system, specifically its inducible form, HO-1. This review collects and updates much of the current knowledge relevant to pharmacology and clinical medicine concerning HO-1 in metabolic diseases and its effect on lipid metabolism.

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Background: Selection of the optimal treatment modality for primary liver cancers remains complex, balancing patient condition, liver function, and extent of disease. In individuals with preserved liver function, liver resection remains the primary approach for treatment with curative intent but may be associated with significant mortality. The purpose of this study was to establish a simple scoring system based on Model for End-stage Liver Disease (MELD) and extent of resection to guide risk assessment for liver resections.

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This Special Issue collates and updates the current knowledge of the pharmacology and clinical applications concerning the enzyme heme oxygenase (HO) [...

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COVID-19 infection causes considerable morbidity and mortality, especially to those who are aged, have impaired renal function and are obese. We propose to examine the potential utility of oral activated charcoal with the hypothesis that such treatment would lower absorption of microbiome derived toxins and ameliorate systemic oxidant stress and inflammation.

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The pathogenesis and molecular pathways involved in non-alcoholic fatty liver disease (NAFLD) are reviewed, as well as what is known about mitochondrial dysfunction that leads to heart disease and the progression to steatohepatitis and hepatic fibrosis. We focused our discussion on the role of the antioxidant gene heme oxygenase-1 (HO-1) and its nuclear coactivator, peroxisome proliferator-activated receptor-gamma coactivator (PGC1-α) in the regulation of mitochondrial biogenesis and function and potential therapeutic benefit for cardiac disease, NAFLD as well as the pharmacological effect they have on the chronic inflammatory state of obesity. The result is increased mitochondrial function and the conversion of white adipocyte tissue to beige adipose tissue ("browning of white adipose tissue") that leads to an improvement in signaling pathways and overall liver function.

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