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Background There are increasing data on changes in intestinal inflammation and microbiome diversity during pregnancy in women with inflammatory bowel disease (IBD) with implications towards individual and offspring immune function. However, differences in intestinal inflammation, as measured by fecal calprotectin (FC) and microbial a-diversity, in consecutive pregnancies are not known. Methods We prospectively enrolled a cohort of women, 37 with IBD and 39 without IBD, during two consecutive pregnancies, and their offspring. We collected serial stool samples and clinical data, and measured FC and bacterial abundance during each trimester of each pregnancy. We further performed correlation analysis between FC in consecutive pregnancies and between microbial a-diversity in consecutive pregnancies among women with and without IBD. Results Compared to healthy controls, IBD pregnancies had significantly lower gestational age at birth and higher frequency of Cesarean section. Mode of delivery, the status of Group B Streptococcus (GBS) infection and GBS infection prophylaxis were significantly associated with the pregnancy order in both IBD and controls (Table). Furthermore, we observed strong correlations of FC (r=0.56, p-value=0.093) and microbial alpha-diversity assessed as operational taxonomic unit (OTU) richness (r=0.88, p=0.0087) between paired consecutive pregnancies in women with IBD, but not in those without IBD (Figure). There were no differences in microbial alpha-diversity using the Shannon and Simpson indices when comparing consecutive pregnancies of women with and without IBD. Conclusion In this study, we demonstrate that intestinal inflammation and microbiome diversity are more conserved in consecutive pregnancies of women with IBD compared to healthy controls. These findings may have implications towards understanding the impact of pregnancy on host-microbiome interactions in IBD as well as the potential impact on offspring health.

Although heart transplantation remains the gold standard for management of heart failure, ventricular assist devices (VAD) have emerged as viable alternatives. VAD implantation improves kidney function. However, whether the improvement is sustained or associated with improved outcomes is unclear. Herein we assess kidney function improvement, predictors of improvement, and associations with thromboembolism, hemorrhage, and mortality in VAD patients. Kidney function was defined using chronic kidney disease (CKD) stages: stage 1 (glomerular filtration rate [eGFR] ≥ 90 ml/min/1.73 m), stage 2 (eGFR 60-90 ml/min/1.73 m), stage 3a (eGFR 45-59 ml/min/1.73 m), stage 3b (eGFR 30-44 ml/min/1.73 m), stage 4 (eGFR 15-30 ml/min/1.73 m), and stage 5 (eGFR15 ml/min/1.73 m). Improvement in kidney function was defined as an improvement in eGFR that resulted in a CKD stage change to one of lesser severity. Kidney function improved post implant, and was maintained over 1 year for all patients, except those with baseline stage 5 CKD. Younger age at implantation (OR 0.93, 95% CI: 0.90-0.96, P0.0001) was associated with sustained improvement in kidney function. Poor kidney function was associated increased mortality but not with thromboembolism or hemorrhage. Compared to patients with baseline eGFR45 ml/min/1.73 m; patients with eGFR45 ml/min/1.73 m had a higher mortality risk (HR 3.32, 95% CI: 1.10-9.98, p = 0.03 for stage 3b; HR 4.07, 95% CI: 1.27-13.1, p = 0.02 for stage 4; and HR 4.01, 95% CI: 1.17-13.7, p = 0.03 for stage 5 CKD). Kidney function was not associated with thromboembolism or hemorrhage, and sustained improvement was not associated with lower risk of death. However, poor kidney function at implantation was associated with an increased risk of mortality.

Myeloid cell populations play critical roles in the context of acute kidney injury and recovery. This chapter provides a description of acute kidney injury and an explanation of the various model systems used to study the mononuclear phagocyte system, with a focus on ischemia–reperfusion injury. The role of cellular damage caused by the initial insult and function of infiltrating versus resident cell populations through injury and recovery, or if there is a failure to restore homeostasis, are discussed.

Background: Acute kidney injury (AKI) is a common sequela of infection with SARS-CoV-2 and contributes to the severity and mortality from COVID-19. Here, we tested the hypothesis that kidney alterations induced by COVID-19-associated AKI could be detected in cells collected from urine. Methods: We performed single-cell RNA sequencing (scRNAseq) on cells recovered from the urine of eight hospitalized COVID-19 patients with (n=5) or without AKI (n=3) as well as four non-COVID-19 AKI patients (n=4) to assess differences in cellular composition and gene expression during AKI. Results: Analysis of 30,076 cells revealed a diverse array of cell types, most of which were kidney, urothelial, and immune cells. Pathway analysis of tubular cells from patients with AKI showed enrichment of transcripts associated with damage-related pathways compared to those without AKI. ACE2 and TMPRSS2 expression were highest in urothelial cells amongst cell types recovered. Notably, in one patient we detected SARS-CoV-2 viral RNA in urothelial cells. These same cells were enriched for transcripts associated with anti-viral and anti-inflammatory pathways. Conclusions: We successfully performed scRNAseq on urinary sediment from hospitalized patients with COVID-19 to noninvasively study cellular alterations associated with AKI and established a dataset that includes both injured and uninjured kidney cells. Additionally, we provide preliminary evidence of direct infection of urinary bladder cells by SARS-CoV-2. The urinary sediment contains a wealth of information and is a useful resource for studying the pathophysiology and cellular alterations that occur in kidney diseases.

BACKGROUND: Mutations affecting cilia proteins have an established role in renal cyst formation. In mice, the rate of cystogenesis is influenced by the age at which cilia dysfunction occurs and whether the kidney has been injured. Disruption of cilia function before postnatal day 12–14 results in rapid cyst formation; however, cyst formation is slower when cilia dysfunction is induced after postnatal day 14. Rapid cyst formation can also be induced in conditional adult cilia mutant mice by introducing renal injury. Previous studies indicate that macrophages are involved in cyst formation, however the specific role and type of macrophages responsible has not been clarified. METHODS: We analyzed resident macrophage number and subtypes during postnatal renal maturation and after renal injury in control and conditional Ift88 cilia mutant mice. We also used a pharmacological inhibitor of resident macrophage proliferation and accumulation to determine the importance of these cells during rapid cyst formation. RESULTS: Our data show that renal resident macrophages undergo a phenotypic switch from R2b (CD11c(lo)) to R2a (CD11c(hi)) during postnatal renal maturation. The timing of this switch correlates with the period in which cyst formation transitions from rapid to slow following induction of cilia dysfunction. Renal injury induces the reaccumulation of juvenile-like R2b resident macrophages in cilia mutant mice and restores rapid cystogenesis. Loss of primary cilia in injured conditional Ift88 mice results in enhanced epithelial production of membrane-bound CSF1, a cytokine that promotes resident macrophage proliferation. Inhibiting CSF1/CSF1-receptor signaling with a CSF1R kinase inhibitor reduces resident macrophage proliferation, R2b resident macrophage accumulation, and renal cyst formation in two mouse models of cystic disease. CONCLUSIONS: These data uncover an important pathogenic role for resident macrophages during rapid cyst progression.

Acute kidney injury (AKI) remains a significant clinical problem through its diverse etiologies, the challenges of robust measurements of injury and recovery, and its progression to chronic kidney disease (CKD). Bridging the gap in our knowledge of this disorder requires bringing together not only the technical resources for research but also the investigators currently endeavoring to expand our knowledge and those who might bring novel ideas and expertise to this important challenge. The University of Alabama at Birmingham-University of California-San Diego O’Brien Center for Acute Kidney Injury Research brings together technical expertise and programmatic and educational efforts to advance our knowledge in these diverse issues and the required infrastructure to develop areas of novel exploration. Since its inception in 2008, this O’Brien Center has grown its impact by providing state-of-the-art resources in clinical and preclinical modeling of AKI, a bioanalytical core that facilitates measurement of critical biomarkers, including serum creatinine via LC-MS/MS among others, and a biostatistical resource that assists from design to analysis. Through these core resources and with additional educational efforts, our center has grown its investigator base to include >200 members from 51 institutions. Importantly, this center has translated its pilot and catalyst funding program with a $37 return per dollar invested. Over 500 publications have resulted from the support provided with a relative citation ratio of 2.18 ± 0.12 (iCite). Through its efforts, this disease-centric O’Brien Center is providing the infrastructure and focus to help the development of the next generation of researchers in the basic and clinical science of AKI. This center creates the promise of the application at the bedside of the advances in AKI made by current and future investigators.

Background Preliminary evidence suggests changes in breast milk cytokines in women with inflammatory bowel disease (IBD) compared to healthy controls, with potential implications toward offspring immunological development. However, changes in breast milk cytokine profiles in consecutive pregnancies are not known. Methods In this pilot study, we prospectively enrolled 11 pregnant women with, and 10 without IBD during two consecutive pregnancies and collected clinical data during each pregnancy and post birth. We collected breast milk samples at two weeks post birth and obtained the expression levels of 92 cytokines using the Olink proteomic platform. We further analyzed the correlation of cytokine profiles within each sample, in paired breast milk samples from consecutive pregnancies, and in random two unpaired breast milk samples, of women with and without IBD. Results The baseline characteristics of women with and without IBD were comparable (Table). The cytokine profiles were significantly correlated between paired breast milk samples from consecutive pregnancies compared to unpaired breast milk samples from women with or without IBD. The overall correlations of cytokine profiles in paired IBD pregnancies were significantly higher than the controls (Figure). Conclusion Our pilot study results suggest that the breast milk cytokine signatures are more conserved in consecutive pregnancies of women with IBD compared to those without IBD. Future analysis will test if our findings have implications toward familial clustering of immune functions in offspring.

Background & Aims The effect of pregnancy on inflammatory bowel disease (IBD) remains poorly understood. We aimed to monitor intestinal inflammation using fecal calprotectin (FC) in pregnant women and their babies during early life. Methods Pregnant women with or without IBD and their infants were prospectively enrolled. FC levels were measured at each trimester of pregnancy and in babies throughout the first 3 years of life. Repeated-measures analysis was applied to investigate changes in FC levels while adjusting for confounders. The FC levels were correlated with the bacterial abundance in both mothers and babies. Results Six hundred and fourteen fecal samples from 358 mothers (98 with IBD) and 1005 fecal samples from 289 infants (76 born to IBD mothers) were analyzed. Pregnant Patients with IBD maintained higher FC levels through pregnancy compared with controls (P = 7.5 × 10–54). FC gradually increased in controls and declined in Patients with IBD throughout pregnancy (P for interaction = 5.8 × 10–7). Babies born to mothers with IBD presented with significantly higher FC levels than those born to controls up to 3 years of age, after adjusting for sex, delivery mode, feeding behavior, and antibiotics exposure (2 weeks to 3 months of age, P = .015; 12–36 months of age, P = .00003). Subdoligranulum, Roseburia, Fusicatenibacter, and Alistipes negatively correlated, and Streptococcus, Prevotella, Escherichia-Shigella, and Bifidobacterium positively correlated with maternal FC levels at T3. Faecalibacterium, Bifidobacterium, and Alistipes showed negative correlations, and Streptococcus were positively correlated with FC levels within 3 months of birth. Conclusions Pregnancy is associated with decreased inflammatory activity in mothers with IBD. Higher FC levels in babies born to mothers with IBD suggest subclinical inflammation in early life, the long-term consequences of which are uncertain.

Lewisite and many other similar arsenicals are warfare vesicants developed and weaponized for use in World Wars I and II. These chemicals, when exposed to the skin and other epithelial tissues, cause rapid severe inflammation and systemic damage. Here, we show that topically applied arsenicals in a murine model produce significant acute kidney injury (AKI), as determined by an increase in the AKI biomarkers NGAL and KIM-1. An increase in reactive oxygen species and ER stress proteins, such as ATF4 and CHOP, correlated with the induction of these AKI biomarkers. Also, TUNEL staining of CHOP-positive renal tubular cells suggests CHOP mediates apoptosis in these cells. A systemic inflammatory response characterized by a significant elevation in inflammatory mediators, such as IL-6, IFN-α, and COX-2, in the kidney could be the underlying cause of AKI. The mechanism of arsenical-mediated inflammation involves activation of AMPK/Nrf2 signaling pathways, which regulate heme oxygenase-1 (HO-1). Indeed, HO-1 induction with cobalt protoporphyrin (CoPP) treatment in arsenical-treated HEK293 cells afforded cytoprotection by attenuating CHOP-associated apoptosis and cytokine mRNA levels. These results demonstrate that topical exposure to arsenicals causes AKI and that HO-1 activation may serve a protective role in this setting.

Altered inflammation and tissue remodeling are cardinal features of cardiovascular disease and cardiac transplant rejection. Neutrophils have increasingly been understood to play a critical role in acute rejection and early allograft failure; however, discrete mechanisms that drive this damage remain poorly understood. Herein, we demonstrate that early acute cardiac rejection increases allograft prolyl endopeptidase (PE) in association with de novo production of the neutrophil proinflammatory matrikine proline-glycine-proline (PGP). In a heterotopic murine heart transplant model, PGP production and PE activity were associated with early neutrophil allograft invasion and allograft failure. Pharmacologic inhibition of PE with Z-Pro-prolinal reduced PGP, attenuated early neutrophil graft invasion, and reduced proinflammatory cytokine expression. Importantly, these changes helped preserve allograft rejection-free survival and function. Notably, within 2 independent patient cohorts, both PGP and PE activity were increased among patients with biopsy-proven rejection. The observed induction of PE and matrikine generation provide a link between neutrophilic inflammation and cardiovascular injury, represent a potential target to reduce allogenic immune responses, and uncover a mechanism of cardiovascular disease that has been previously unrecognized to our knowledge.

Chronic kidney disease (CKD) is a condition with significant morbidity and mortality that affects 15% of adults in the United States. One cause of CKD is acute kidney injury (AKI), which commonly occurs secondary to sepsis, ischemic events, and drug-induced nephrotoxicity. Unilateral ischemia-reperfusion injury (UIRI) without contralateral nephrectomy (CLN) and repeated low-dose cisplatin (RLDC) models of AKI to CKD demonstrate responses characteristic of the transition; however, previous studies have not effectively compared the pathogenesis. We demonstrate both models instigate renal dysfunction, inflammatory cytokine responses, and fibrosis. However, the models exhibit differences in urinary excretory function, inflammatory cell infiltration, and degree of fibrotic response. UIRI without CLN demonstrated worsening perfusion and function, measured with 99mTc-mercaptoacetyltriglycine-3 imaging, and physiologic compensation in the contralateral kidney. Furthermore, UIRI without CLN elicited a robust inflammatory response that was characterized by a prolonged polymorphonuclear cell and natural killer cell infiltrate and an early expansion of kidney resident macrophages, followed by T-cell infiltration. Symmetrical diminished function occurred in RLDC kidneys and progressively worsened until day 17 of the study. Surprisingly, RLDC mice demonstrated a decrease in inflammatory cell numbers relative to controls. However, RLDC kidneys expressed increased levels of kidney injury molecule-1 (KIM-1), high mobility group box-1 ( HMGB1), and colony stimulating factor-1 ( CSF-1), which likely recruits inflammatory cells in response to injury. These data emphasize how the divergent etiologies of AKI to CKD models affect the kidney microenvironment and outcomes. This study provides support for subtyping AKI by etiology in human studies, aiding in the elucidation of injury-specific pathophysiologic mechanisms of the AKI to CKD transition.

Gastrointestinal bleeding (GIB) is common in patients with continuous-flow left ventricular assist devices (CF-LVADs) possibly because of changes in blood flow. We aimed to test the hypothesis that a low pulsatility index (PI) is associated with an increased hazard of overt GIB in patients with CF-LVADs. We conducted a retrospective cohort study of patients who had a HeartMate II (HMII) CF-LVAD implanted at our center. The study end-point was the first overt GIB causing or occurring during a hospitalization between 6 days and 6 months after HMII implantation. HMII PI was recorded at 48 hours and at 1, 3, and 6 month intervals after implantation. We analyzed the associations of PI and clinical variables with the hazard of overt GIB. Ninety-five patients met eligibility criteria. PI ranged from 2.5 to 5.9 (low PI < 4.15 and high PI ≥ 4.15 on the basis of receiver operating characteristic curve analysis). Seventeen (18%) patients experienced overt GIB. In a multivariable model, only lower baseline hemoglobin was a significant predictor of an increased hazard of overt GIB. After adjusting for the baseline hemoglobin, low PI was independently associated with an increased hazard of overt GIB in our cohort of HMII recipients.

Ferroptosis is an iron-dependent form of regulated nonapoptotic cell death, which contributes to damage in models of acute kidney injury (AKI). Heme oxygenase-1 (HO-1) is a cytoprotective enzyme induced in response to cellular stress, and is protective against AKI because of its antiapoptotic and anti-inflammatory properties. However, the role of HO-1 in regulating ferroptosis is unclear. The purpose of this study was to elucidate the role of HO-1 in regulating ferroptotic cell death in renal proximal tubule cells (PTCs). Immortalized PTCs obtained from HO-1+/+ and HO-1−/− mice were treated with erastin or RSL3, ferroptosis inducers, in the presence or absence of antioxidants, an iron source, or an iron chelator. Cells were assessed for changes in morphology and metabolic activity as an indicator of cell viability. Treatment of HO-1+/+ PTCs with erastin resulted in a time- and dose-dependent increase in HO-1 gene expression and protein levels compared with vehicle-treated controls. HO-1−/− cells showed increased dose-dependent erastin- or RSL3-induced cell death in comparison to HO-1+/+ PTCs. Iron supplementation with ferric ammonium citrate in erastin-treated cells decreased cell viability further in HO-1−/− PTCs compared with HO-1+/+ cells. Cotreatment with ferrostatin-1 (ferroptosis inhibitor), deferoxamine (iron chelator), or N-acetyl-l-cysteine (glutathione replenisher) significantly increased cell viability and attenuated erastin-induced ferroptosis in both HO-1+/+ and HO-1−/− PTCs. These results demonstrate an important antiferroptotic role of HO-1 in renal epithelial cells.

Anticoagulation control has been associated with risk of thromboembolism and hemorrhage. Herein, we explore the relationship between anticoagulation control achieved in left ventricular assist device (LVAD) patients and evaluate the association with risk of thromboembolism and hemorrhage. Patients (19 years old or older) with a continuous flow LVAD placed from 2006 to 2012. Percent time spent in target range (PTTR) for international normalized ratio (INR) was estimated with target range of 2.0-3.0. Proportion of time spent in target range was categorized into PTTR60%, PTTR ≥ 5060%, and PTTR50%. The relationship between PTTR and thromboembolism and hemorrhage was assessed. One hundred fifteen participants contributed 624.5 months of follow-up time. Only 20% of patients achieved anticoagulation control (PTTR60% for INR range of 2-3). After adjusting for chronic kidney disease, history of diabetes, history of atrial fibrillation, and age at implant, compared with patients with PTTR50%, the relative risk of thromboembolism in patients with PTTR ≥ 60% (hazard ratio [HR]: 0.37; 95% confidence interval [CI]: 0.14-0.96; p = 0.042) was significantly lower, but not for patients with a PTTR of ≥ 5060% (HR: 0.21; 95% CI: 0.02-1.82; p = 0.16). The relative risk for hemorrhage was also significantly lower among patients with a PTTR ≥ 60% (HR: 0.45; 95% CI: 0.21-0.98; p = 0.045), but not among those with PTTR of ≥ 5060% (HR: 0.47; 95% CI: 0.14-1.56; p = 0.22). This current study demonstrates that LVAD patients remain in the INR target range an average of 42.9% of the time. To our knowledge, this is the first report with regard to anticoagulation control as assessed by PTTR and its association with thromboembolism, hemorrhage, or death among patients with ventricular assist devices (VADs).

Acute kidney injury (AKI) is a devastating clinical condition affecting at least two-thirds of critically ill patients, and, among these patients, it is associated with a greater than 60% risk of mortality. Kidney mononuclear phagocytes (MPs) are implicated in pathogenesis and healing in mouse models of AKI and, thus, have been the subject of investigation as potential targets for clinical intervention. We have determined that, after injury, F4/80(hi)-expressing kidney-resident macrophages (KRMs) are a distinct cellular subpopulation that does not differentiate from nonresident infiltrating MPs. However, if KRMs are depleted using polyinosinic/polycytidylic acid (poly I:C), they can be reconstituted from bone marrow–derived precursors. Further, KRMs lack major histocompatibility complex class II (MHCII) expression before P7 but upregulate it over the next 14 days. This MHCII(–) KRM phenotype reappears after injury. RNA sequencing shows that injury causes transcriptional reprogramming of KRMs such that they more closely resemble that found at P7. KRMs after injury are also enriched in Wingless-type MMTV integration site family (Wnt) signaling, indicating that a pathway vital for mouse and human kidney development is active. These data indicate that mechanisms involved in kidney development may be functioning after injury in KRMs.

Background and aimsPrenatal and early life bacterial colonisation is thought to play a major role in shaping the immune system. Furthermore, accumulating evidence links early life exposures to the risk of developing IBD later in life. We aimed to assess the effect of maternal IBD on the composition of the microbiome during pregnancy and on the offspring’s microbiome.MethodsWe prospectively examined the diversity and taxonomy of the microbiome of pregnant women with and without IBD and their babies at multiple time points. We evaluated the role of maternal IBD diagnosis, the mode of delivery, antibiotic use and feeding behaviour on the microbiome composition during early life. To assess the effects of IBD-associated maternal and infant microbiota on the enteric immune system, we inoculated germ-free mice (GFM) with the respective stool and profiled adaptive and innate immune cell populations in the murine intestines.ResultsPregnant women with IBD and their offspring presented with lower bacterial diversity and altered bacterial composition compared with control women and their babies. Maternal IBD was the main predictor of the microbiota diversity in the infant gut at 7, 14, 30, 60 and 90 days of life. Babies born to mothers with IBD demonstrated enrichment in Gammaproteobacteria and depletion in Bifidobacteria. Finally, GFM inoculated with third trimester IBD mother and 90-day infant stools showed significantly reduced microbial diversity and fewer class-switched memory B cells and regulatory T cells in the colon.ConclusionAberrant gut microbiota composition persists during pregnancy with IBD and alters the bacterial diversity and abundance in the infant stool. The dysbiotic microbiota triggered abnormal imprinting of the intestinal immune system in GFM.

Significance: Acute kidney injury (AKI) and chronic kidney disease (CKD) represent a considerable burden in healthcare. The heme oxygenase (HO) system plays an important role in regulating oxidative stress and is protective in a variety of human and animal models of kidney disease. Preclinical studies of the HO system have led to the development of several clinical trials targeting the enzyme or its products. Recent Advances: Connection of HO, ferritin, and other proteins involved in iron regulation has provided important insight into mechanisms of damage in AKI. Also, HO-1 expression is important in the pathogenesis of hypertension, diabetic kidney disease, and progression to end-stage renal disease. Critical Issues: Despite intriguing discoveries, no drugs targeting the HO system have been translated to the clinic. Meanwhile, treatments for AKI and CKD are urgently needed. Many factors have likely contributed to challenges in clinical translation, including variation in animal models, difficulties in obtaining human tissue, and complexity of the disease processes being studied. Future Directions: The HO system represents a promising avenue of investigation that may lead to targeted therapeutics. Tissue-specific gene modulation, widening the scope of animal studies, and continued clinical research will provide valuable insight into the role HO plays in kidney homeostasis and disease. Antioxid. Redox Signal. 25, 165–183.

To identify factors that regulate gut microbiota density and the impact of varied microbiota density on health, we assayed this fundamental ecosystem property in fecal samples across mammals, human disease, and therapeutic interventions. Physiologic features of the host (carrying capacity) and the fitness of the gut microbiota shape microbiota density. Therapeutic manipulation of microbiota density in mice altered host metabolic and immune homeostasis. In humans, gut microbiota density was reduced in Crohn’s disease, ulcerative colitis, and ileal pouch-anal anastomosis. The gut microbiota in recurrent Clostridium difficile infection had lower density and reduced fitness that were restored by fecal microbiota transplantation. Understanding the interplay between microbiota and disease in terms of microbiota density, host carrying capacity, and microbiota fitness provide new insights into microbiome structure and microbiome targeted therapeutics.Editorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter).

Cardiac surgery causes direct trauma to cardiac tissue, breaches the pericardium, and disrupts the normal composition of the fluid largely produced from the myocardial interstitium and epicardial and visceral pericardium. This leaves the heart exposed to pericardial fluid (PCF) and mediastinal contents comprising inflammatory cells and their products that now bathe the heart. This can potentially have adverse effects on the thin-walled atria leading to postoperative atrial fibrillation (AF).1 After cardiac surgery, the pericardium remains open, and chest drains are routinely placed to prevent fluid accumulation around the heart. Here, we describe the concentration and trajectory of blood proinflammatory factors in the PCF after cardiac surgery over time. The study protocol was approved by the University of Alabama at Birmingham. Institutional Review Board approval and informed consent were obtained from all patients. PCF (n=19) was collected immediately after pericardiotomy (time 0) and from the pericardial drains at times 4, 12, 24, and 48 hours after surgery. The patient population (mean age, 60±3 years) included 26.3% women and 26.3% blacks undergoing cardiac surgery (coronary artery bypass graft, n=14; coronary artery bypass graft+valve procedure, n=3; valve procedure alone, n=2). Patients with ventricular assist devices, AF surgery, thoracic aorta surgery, and AF within 6 months prior were excluded. All participants who had valve replacement (with or without coronary artery bypass graft) underwent on-pump surgeries. Of the patients undergoing coronary artery bypass …

Mutations in the leucine-rich repeat kinase 2 (LRRK2) gene are the most common known genetic cause of Parkinson's disease, and LRRK2 is also linked to Crohn's and Hansen's disease. LRRK2 is expressed in many organs in mammals but is particularly abundant in the kidney. We find that LRRK2 protein is predominantly localized to collecting duct cells in the rat kidney, with much lower expression in other kidney cells. While genetic knockout (KO) of LRRK2 expression is well-tolerated in mice and rats, a unique age-dependent pathology develops in the kidney. The cortex and medulla of LRRK2 KO rat kidneys become darkly pigmented in early adulthood, yet aged animals display no overt signs of kidney failure. Accompanying the dark pigment we find substantial macrophage infiltration in LRRK2 KO kidneys, suggesting the presence of chronic inflammation that may predispose to kidney disease. Unexpectedly, the dark kidneys of the LRRK2 KO rats are highly resistant to rhabdomyolysis-induced acute kidney injury compared with wild-type rats. Biochemical profiling of the LRRK2 KO kidneys using immunohistochemistry, proteomic and lipidomic analyses show a massive accumulation of hemoglobin and lipofuscin in renal tubules that account for the pigmentation. The proximal tubules demonstrate a corresponding up-regulation of the cytoprotective protein heme oxygenase-1 (HO-1) which is capable of mitigating acute kidney injury. The unusual kidney pathology of LRRK2 KO rats highlights several novel physiological roles for LRRK2 and provides indirect evidence for HO-1 expression as a protective mechanism in acute kidney injury in LRRK2 deficiency.

Atherosclerosis and valvular heart disease often require treatment with corrective surgery to prevent future myocardial infarction, ischemic heart disease, and heart failure. Mechanisms underlying the development of the associated complications of surgery are multifactorial and have been linked to inflammation and oxidative stress, classically as measured in the blood or plasma of patients. Post-operative pericardial fluid (PO-PCF) has not been investigated in depth with respect to the potential to induce oxidative stress. This is important since cardiac surgery disrupts the integrity of the pericardial membrane surrounding the heart, and causes significant alterations in the composition of the pericardial fluid (PCF). This includes contamination with hemolyzed blood and high concentrations of oxidized hemoglobin, which suggests that cardiac surgery results in oxidative stress within the pericardial space. Accordingly, we tested the hypothesis that PO-PCF is highly pro-oxidant and that the potential interaction between inflammatory cell-derived hydrogen peroxide with hemoglobin is associated with oxidative stress. Blood and PCF were collected from 31 patients at the time of surgery and postoperatively from 4 to 48 hours after coronary artery bypass grafting, valve replacement, or valve repair (mitral or aortic). PO-PCF contained high concentrations of neutrophils and monocytes which are capable of generating elevated amounts of superoxide and hydrogen peroxide through the oxidative burst. In addition, PO-PCF primed naïve neutrophils resulting in an enhanced oxidative burst upon stimulation. The PO-PCF also contained increased concentrations of cell-free oxidized hemoglobin which was associated with elevated levels of F2α-isoprostanes and prostaglandins, consistent with both oxidative stress and activation of cyclooxygenase. Lastly, protein analysis of the PO-PCF revealed evidence of protein thiol oxidation and protein carbonylation. We conclude that PO-PCF is highly pro-oxidant and speculate that it may contribute to the risk of post-operative complications.

Obscure overt gastrointestinal bleeding (OGIB) is a challenge in patients with left ventricular assist devices (LVADs). We evaluated the utility and safety of double-balloon enteroscopy (DBE) in patients with LVADs in an observational consecutive-patient cohort from a single tertiary referral center. Ten patients with LVADs underwent thirteen DBEs for obscure OGIB. The first OGIB event necessitating DBE occurred after a mean of 512 ± 363 days of LVAD support. All patients underwent DBE, eleven anterograde and two retrograde, with a mean insertion depth 176 ± 85 cm. Diagnostic yield was 69 % with the primary bleeding lesion most frequently found in the mid-bowel. The most common lesions were arteriovenous malformations. Therapeutic yield with argon plasma coagulation (APC), epinephrine injection, and/or hemoclip placement was 89 %. There were no procedure-related complications. DBE in patients with LVADs has good diagnostic yield and high therapeutic yield for obscure OGIB and is safe and well tolerated.

Background The pediatric heart transplant literature contains little information regarding extracorporeal photopheresis (ECP), despite International Society for Heart and Lung Transplantation guidelines recommending it for recurrent/recalcitrant rejection. We report our experience with ECP in pediatric heart transplantation. Methods Data were obtained on heart transplant patients who were aged ≤ 18 years at the time of transplantation and received ECP between 1990 and 2012 at our institution. Results Twenty heart transplant patients underwent 22 courses of ECP. Median ages were 12.7 years (range, 0.3–18.5 years) at transplant and 15.3 years (range, 7.3–31 years) at initial ECP. Median time from transplant to ECP was 1.4 years (range, 0.1–12.6 years). The median ECP duration was 5.8 months (range, 1.9–16.1 months). Indications for ECP included rejection with hemodynamic compromise (HC) in 4 patients, rejection without HC in 12, and prophylaxis in 2. Eleven patients died at a median time of 3.1 years after the start of ECP. Survival after ECP was 84% at 1 year and 53% at 3 years. Eleven patients were considered non-compliant and had a trend toward lower survival of 75% at 1 year and 18% at 3 years ( p = 0.06 compared with compliant patients). One patient developed Pneumocystis carinii pneumonia during ECP and post-transplant lymphoproliferative disease 21 months after finishing ECP. No other adverse effects or infectious complications associated with ECP were noted. Conclusions This case series represents the largest reported experience with ECP in pediatric heart transplantation. ECP can be safely applied in this patient group. Despite EPC, non-compliant patients showed a trend toward lower survival than compliant patients.

The purpose of these studies was to determine the incidence and survival of patients with specific malignancies with respect to age and transplant year and to compare the data with the normal non-transplant population.Data from 6,211 primary cardiac transplants between July 31, 1993, and December 30, 2008, were collected by 35 institutions participating in the Cardiac Transplant Research Database. Data were compared with information collected by the Surveillance Epidemiology and End Results (SEER) Cancer Statistics Review 1975-2006.Multivariable analysis showed older age (relative risk [RR], 2.1; p0.0001) and earlier transplant year (RR, 1.8; p0.0001) were highly significant risk factors. Aggregate malignancy incidence in the modern era (2001 to 2008) did not differ significantly from the normal population, which appeared to be attributable to a lower rate of malignancies other than lung cancer, lymphoma, and melanoma (actual/expected ratio, 0.71). From 2001 to 2008, rates were significantly higher for lung cancer (actual/expected ratio, 1.86; p = 0.006) and lymphoma (actual/expected ratio, 4.3, p0.0001) than in the normal population. The highest risk for lymphoma was in younger adults who received transplants at ages 18 to 35 years (actual/expected ratio, 27). The highest risk for lung cancer was in patients who underwent transplantation at ages 55 to 65 years (actual/expected ratio, 28). Once diagnosed with malignancy, subsequent survival at 5 years was 21% for lung cancer and 32% for lymphoma.The risk of malignancy has markedly declined during a 15-year period such that the aggregate rate of malignancy approached that of the general population in the United States. However, the distribution of malignancies was not the same, with a greater prominence of lung cancer and lymphoproliferative disease.

Coronary spasm during coronary angiography for vasculopathy in children can be prevented by the intracoronary administration of nitroglycerin. We reviewed the anesthesia and catheterization reports and charts for pediatric transplant recipients who underwent angiography from 2005 through 2010. Correlation analysis was used to study the relation of post-injection systolic blood pressure (SBP) to nitroglycerin dose. Forty-one angiographic evaluations were performed on 25 patients (13 male and 12 female). Mean age was 9.9 ± 3.2 years (range, 3.3–16.1 yr). The mean total dose of nitroglycerin was 2.93 ± 1.60 µg/kg (range, 1–8 µg/kg). There was a significant drop between the baseline SBP (mean, 106 ± 21.6 mmHg) and the lowest mean SBP before nitroglycerin administration (78 ± 13.2, P

Ventricular assist device implantation is associated with gastrointestinal bleeding (GIB); however, outcomes in terms of initial and repeat GIB risk, severity, location of lesions, and endoscopic interventions need to be better defined. Consecutive patients from a database of adult patients with ventricular assist devices (VADs) implanted between January 1, 2000, and December 31, 2010, at a single center were reviewed and followed through May 31, 2011, in a retrospective manner. The GIB events were further classified by severity, lesion location, and lesion type. Hazard analysis models were calculated for the time to GIB events. Of 166 patients with a VAD, 38 patients experienced 84 GIB events. Seventeen patients experienced ≥2 GIB events. Maximal hazard for the first bleeding event was 2.23 events/patient-year at 21 days and declined to the constant hazard by 71 days postimplantation. The hazard for recurrent GIB was greatest immediately after the first GIB event. When considering all GIB events, most lesions (68%) were located in the proximal bowel. Angiodysplasia was the most common lesion type (17.5%) seen on endoscopy when all GIB events were considered, whereas ulcers were the most common type (13.8%) seen in initial GIB events. The actuarial risk of initial GIB events peaks in the first 3 months after VAD implantation followed by a stable lower risk of bleeding. The hazard for recurrent GIB events is substantially increased immediately after the initial GIB.

Although short-term outcomes in kidney transplantation have improved dramatically, long-term survival remains a major challenge. A key component of long-term, chronic allograft injury in solid organ transplants is arteriosclerosis characterized by vascular neointimal hyperplasia and inflammation. Establishing a model of this disorder would provide a unique tool not only to identify mechanisms of disease but also to test potential therapeutics for late graft injury. To this end, we utilized a mouse orthotopic renal transplant model in which C57BL/6J (H-2b) recipients were given either a kidney allograft from a completely mismatched Balb/cJ mouse (H-2d) or an isograft from a littermate. A unilateral nephrectomy was performed at the time of transplant followed by a contralateral nephrectomy on post-transplant day 7. Recipients were treated with daily cyclosporine subcutaneously for 14 days and then studied 8 and 12 weeks post transplantation. Renal function was significantly worse in allograft compared with isograft recipients. Moreover, the allografts had significantly more advanced tubulointerstitial fibrosis and profound vascular disease characterized by perivascular leukocytic infiltration and neointimal hyperplasia affecting the intrarenal blood vessels. Thus, we describe a feasible and reproducible murine model of intrarenal transplant arteriosclerosis that is useful to study allograft vasculopathy.

Mononuclear phagocytes are the most common cells in the kidney associated with immunity and inflammation. Although the presence of these cells in the kidney has been known for decades, the study of mononuclear phagocytes in the context of kidney function and dysfunction is still at an early stage. The purpose of this review is to summarize the present knowledge regarding classification of these cells in the mouse kidney and to identify relevant questions that would further advance the field and potentially lead to new opportunities for treatment of acute kidney injury and other kidney diseases.

Determining optimal timing for implant of ventricular assist device (VAD) in end-stage heart failure remains a challenge and may be aided by a risk assessment tool. For a cohort of 80 consecutive VAD implants at a single center, observed 1 year survival post-VAD was compared with the estimated survival had these patients not received a VAD, using the Seattle Heart Failure Model (SHFM). The SHFM was adjusted with a hazard ratio of 1.17 for inotrope use (Cochrane Meta-analysis of phosphodiesterase inhibitors) and a hazard ratio of 2.92 for balloon pump, ventilator, or renal replacement therapy (Comparative Outcome and Clinical Profiles in Transplantation [COCPIT] Model). Values immediately before surgery were used to calculate the SHFM score. Point estimates of 1 year survival were compared using Z scores. Mean age was 53 ± 14 (± standard deviation [SD]) years with mean left ventricular ejection fraction of 17 ± 6%. At the time of VAD implant, 92% were on inotropes, 53% had balloon pump, and 15% were intubated. For the entire cohort, 1 year survival without VAD predicted by the SHFM was 47% versus observed survival after VAD of 60% (p = 0.06). The model was most helpful in patients electively implanted with a left ventricular assist device (LVAD). In this group predicted 1 year survival on medical management was 49% versus an observed survival of 82% after LVAD placement (p < 0.05). The model was least helpful in patients undergoing placement of biventricular assist devices (BiVAD), where the model paradoxically predicted better survival with ongoing medical management. This indicated that the model was unable to forecast outcome in patients with higher severity of illness, for example, in cases warranting BiVAD placement. Observed 1 year survival was better with VAD versus that predicted with medical management. Tools such as the SHFM may aid in determining appropriate timing for VAD by providing an estimated survival with ongoing medical management. The model is best applied to more stable patients being considered for elective VAD implantation.

Background.Totallymphoidirradiation(TLI)hasbeenusedintransplantationforover20yearsandiscurrentlyused in a number of major heart transplant centers as a secondary therapy for recalcitrant recurrent rejection or rejection with hemodynamic compromise. The purpose of this study is to evaluate the long-term risks and efficacy of TLI in the treatment of rejection. Methods. Between 1990 and 1996, 73 adult patients (from 211 adult transplant recipients) received TLI for recurrent rejection (71%), rejection with hemodynamic compromise (25%), and rejection with vasculitis (4%). The treatment consisted of 80 cGy twice per week for 5 weeks. Fifty-five patients received at least 80% of the full dose (640 cGy). Follow-up ended December 31, 2007, comprising a total 18 year experience. Results. Patients treated with TLI exhibited a short-term decrease in hazard for rejection in the first 12 months posttransplantation (relative risk, 0.36) but exhibited increased cumulative rejection over the long term. There were no differences in the rates of infection, allograft coronary disease, or malignancy, but seven patients developed myelodysplasia or acute myelogenous leukemia, four of those being the rare but uniformly fatal acute megakaryocytic leukemia type 7. Conclusions. Patients treated with TLI seemed to experience a reduction in the early hazard for rejection, but longterm outcomes indicate that such patients continued to accumulate more rejection and rejection-death events, likely because these patients were overall at much higher risk for rejection than the other patient groups. We observed minimal long-term complications, except for the unique occurrence of myelodysplasia and acute megakaryocytic leukemia type 7.

Background: A carbon monoxide-releasing molecule (tricarbonyldichlororuthenium (II) dimer; CORM-2) enhances coagulation and attenuates vulnerability to fibrinolysis in normal and hemophiliac human plasma. We tested the hypothesis that plasma diluted with resuscitative fluids would demonstrate improved coagulation and decreased fibrinolytic vulnerability after exposure to CORM-2. Methods: Normal, platelet-poor plasma was diluted 0%, 20%, 30%, 40%, or 50% with 0.9% NaCl (NS) or low-molecular-weight hydroxyethyl starch (VOL) and, subsequently, exposed to 0 μmol/L or 100 μmol/L CORM-2 before activation with tissue factor (n = 4 per condition). Additional plasma samples diluted with NS or VOL (0% or 30%) were exposed to 0 μmol/L or 100 μmol/L CORM-2 and 0 U/mL or 100 U/mL tissue-type plasminogen activator to assess fibrinolytic vulnerability (n = 8 per condition). Thrombelastographic data were collected until either clot strength stabilized or clot lysis occurred, as appropriate. Results: CORM-2 exposure maintained normal to supranormal velocity of clot formation and strength in plasma diluted up to 40% with NS. In contrast, although CORM-2 exposure improved coagulation kinetics, dilution with VOL markedly degraded thrombus formation kinetics. Similarly, fibrinolytic vulnerability to tissue-type plasminogen activator was markedly improved by CORM-2 exposure in samples diluted with NS, whereas VOL-diluted thrombi were still abnormally weak and easily lysed compared with undiluted samples despite CORM-2 exposure. Conclusions: CORM-2 exposure attenuated the decrease in coagulation kinetics and enhancement of fibrinolytic vulnerability associated with hemodilution. Extensive preclinical investigation remains to be performed to determine the route of administration, safety, and efficacy of CORM-2 and other CORMs to treat trauma-associated bleeding.

The purpose of this study is to describe the utility and limitations of gated contrast-enhanced cardiac computed tomography angiography in assessing left ventricular assist device function. Computed tomography angiography (CTA) was used in 14 patients with left ventricular assist devices (LVADs) who had persistent heart failure symptoms, hemodynamic instability, or potential problems with LVAD flows. Retrospectively gated contrast-enhanced CTA was performed on 64-detector scanner, and the CTA images were postprocessed in multiple curved projections on TeraRecon workstation. This study describes the use of CTA to identify LVAD-related issues that altered clinical management and explores the role of CTA and other techniques in evaluating LVAD function. Six of 14 LVAD patients who demonstrated no abnormality on CTA remained stable with medical management. In the remaining eight patients, CTA was abnormal, including abnormalities specifically related to the LVAD cannula. As a result of findings detected by CTA, six patients underwent surgical intervention, including device exchange and heart transplant. Computed tomography angiography is a noninvasive method that enhances diagnostic evaluation of patients with suspected LVAD dysfunction and can lead to changes in patient management.

Carbon monoxide derived from degradation of heme by heme oxygenase or carbon monoxide releasing molecules (CORMs) has been demonstrated to decrease thrombosis in vivo and to weakly inhibit platelet aggregation. We tested the hypothesis that carbon monoxide released from tricarbonyldichlororuthenium (II) dimer (CORM-2) would diminish the velocity of formation and strength of plasma thrombi as determined by thrombelastography. Normal plasma was exposed to 0 or 100 micromol/l CORM-2 or inactivated CORM-2 (iCORM-2), with coagulation initiated with tissue factor or celite (n = 8 per condition). Additional experiments utilized factor XIII (FXIII) deficient plasma activated with celite. Coagulation kinetics was monitored with thrombelastography for 15 min. CORM-2, and to a lesser extent, iCORM-2, significantly (P0.05) increased the velocity of formation (122 and 56%, respectively) and strength (66 and 57%, respectively) of plasma clots initiated with either tissue factor or celite compared with thrombi not exposed to CORM-2 or iCORM. In FXIII deficient plasma CORM-2 significantly increased the velocity of clot formation (264%) and strength (240%). Carbon monoxide and iCORM-2 derived from CORM-2 markedly enhance the velocity of clot growth and strength. These findings serve as the rationale for further investigations to determine if CORMs could be utilized as hemostatic agents.

Heme oxygenase-1 (HO-1) catalyzes the conversion of heme into carbon monoxide (CO), iron, and biliverdin. In preliminary studies, we observed that the absence of HO-1 in aortic allograft recipients resulted in 100% mortality within 4 days due to arterial thrombosis. In contrast, recipients normally expressing HO-1 showed 100% graft patency and survival for more than 56 days. Abdominal aortic transplants were performed using Balb/cJ mice as donors and either HO-1(+/+) or HO-1(-/-) (C57BL/6xFVB) mice as recipients. Light and electron microscopy revealed extensive platelet-rich thrombi along the entire length of the graft in HO-1(-/-) recipients at 24 hours. Treatment of recipients with CORM-2, a CO-releasing molecule (10 mg/kg of body weight intravenously), 1 hour prior and 1, 3, and 6 days after transplantation, significantly improved survival (62% at56 days, P0.001) compared with HO-1(-/-) recipients treated with inactive CORM-2 (median survival 1 day). Histological analyses revealed that CO treatment markedly reduced platelet aggregation within the graft. Adoptive transfer of wild-type platelets to HO-1(-/-) recipients also conferred protection and increased survival. Aortic transplants from either HO-1(-/-) or HO-1(+/+) C57BL/6 donors into HO-1(+/+) (Balb/cJ) mice did not develop arterial thrombosis, surviving more than 56 days. These studies demonstrate an important role for systemic HO-1/CO for protection against vascular arterial thrombosis in murine aortic allotransplantation.

This review considers the perhaps unappreciated role of contact pathway proteins in the pathogenesis of thrombotic/thromboembolic morbidity associated with mechanical circulatory support. Placement of ventricular assist devices (VADs) has been associated with consumption of circulating contact proteins and persistent generation of activated contact proteins such as Factor XII and high molecular weight kininogen. Importantly, activated contact proteins are absorbed to the surface of VADs via the Vroman effect. Further, hyperfibrinogenemia and persistent platelet activation exist in patients with VADs, likely contributing to speed of clot growth. Using thrombelastographic-based analyses, it has been determined that contact pathway protein activated coagulation results in a thrombus that develops strength at a significantly faster rate that tissue factor initiated coagulation. Further, thrombelastographic analyses that include the addition of tissue-type plasminogen activator have demonstrated that contact protein pathway activation results in thrombin activatable fibrinolysis inhibitor activation to a far greater extent than that observed with tissue factor initiated coagulation, resulting in a thrombus that takes significantly longer to lyse. These observations serve as the rational basis for clinical investigation to determine if regional suppression of thrombin generation with FXII/high molecular weight kininogen inhibition in concert with thrombin-activatable fibrinolysis inhibitor inhibition may decrease mechanical circulatory support-associated thrombotic morbidity.

Intravenous cyclosporine (i.v. CsA) is an effective therapy for patients with inflammatory bowel disease (IBD). However, data regarding its adverse events in these patients are limited.A retrospective chart review of the initial 111 consecutive patients with IBD treated with i.v. CsA followed by a predetermined duration of oral therapy.One hundred eleven patients (64 UC, 47 CD; mean age 33 yr, range 16-68) received i.v. CsA at 4 mg/kg/day, then oral CsA at 8 mg/kg/day, with dose adjustment based on serum creatinine. The mean treatment duration was 9.3 months (range 1 wk to 34 months). Major adverse events occurred in 17 (15.3%) patients. Nephrotoxicity (serum creatinineor = 1.4 mg/dL [123 micromol/L] or a rise by at least 33% over baseline not responding to dose adjustment) sufficiently severe to warrant discontinuation of therapy occurred in 6 (5.4%) patients. Serious infection occurred in 7 (6.3%) patients, seizures in 4 (3.6%) patients, anaphylaxis in 1 (0.9%) patient, and death in 2 (1.8%) patients. Minor adverse events (transient effects with complete resolution either spontaneously or with dose adjustment) comprised: paresthesias (51%), hypomagnesemia (42%), hypertension (39%), hypertrichosis (27%), headache (23%), minor nephrotoxicity (defined as above but with restoration of normal serum creatinine with dose adjustment; 19% of patients), abnormal liver function tests (19%), minor infections (15%), hyperkalemia (13%), and gingival swelling (4%).In our initial experience, limited duration CsA therapy was frequently associated with adverse events although the majority of these were minor and responded to dose adjustment. Although not all severe adverse events can be clearly attributed to CsA use alone, its high incidence suggests that vigorous monitoring by experienced clinicians at tertiary care centers may be required.

The deposited article is a post-print version (author's manuscript from PMC). This publication hasn't any creative commons license associated. The deposited article version contains attached the supplementary materials within the pdf. Inflammation culminating in fibrosis contributes to progressive kidney disease. Cross-talk between the tubular epithelium and interstitial cells regulates inflammation by a coordinated release of cytokines and chemokines. Here we studied the role of heme oxygenase-1 (HO-1) and the heavy subunit of ferritin (FtH) in macrophage polarization and renal inflammation. Deficiency in HO-1 was associated with increased FtH expression, accumulation of macrophages with a dysregulated polarization profile, and increased fibrosis following unilateral ureteral obstruction in mice: a model of renal inflammation and fibrosis. Macrophage polarization in vitro was predominantly dependent on FtH expression in isolated bone marrow-derived mouse monocytes. Using transgenic mice with conditional deletion of FtH in the proximal tubules (FtH(PT-/-)) or myeloid cells (FtH(LysM-/-)), we found that myeloid FtH deficiency did not affect polarization or accumulation of macrophages in the injured kidney compared with wild-type (FtH(+/+)) controls. However, tubular FtH deletion led to a marked increase in proinflammatory macrophages. Furthermore, injured kidneys from FtH(PT-/-) mice expressed significantly higher levels of inflammatory chemokines and fibrosis compared with kidneys from FtH(+/+) and FtH(LysM-/-) mice. Thus, there are differential effects of FtH in macrophages and epithelial cells, which underscore the critical role of FtH in tubular-macrophage cross-talk during kidney injury. NIH grants: (R01 DK5960, R01 DK5960, P30 DK079337, R01 DK083390); Fundação para a Ciência e Tecnologia grants: (PTDC/SAU-TOX/116627/2010, HMSP-ICT/0022/2010); European Union grant: (ERC-2011-AdG. 294709 DAMAGECONTROL); AHA grant: (11POST7600074). info:eu-repo/semantics/publishedVersion

Renal ischemia-reperfusion injury is mediated by a complex cascade of events, including the immune response, that occur secondary to injury to renal epithelial cells. We tested the hypothesis that heme oxygenase-1 (HO-1) expression, which is protective in ischemia-reperfusion injury, regulates trafficking of myeloid-derived immune cells in the kidney. Age-matched male wild-type (HO-1(+/+)), HO-1-knockout (HO-1(-/-)), and humanized HO-1-overexpressing (HBAC) mice underwent bilateral renal ischemia for 10 minutes. Ischemia-reperfusion injury resulted in significantly worse renal structure and function and increased mortality in HO-1(-/-) mice. In addition, there were more macrophages (CD45(+) CD11b(hi)F4/80(lo)) and neutrophils (CD45(+) CD11b(hi) MHCII(-) Gr-1(hi)) in HO-1(-/-) kidneys than in sham and HO-1(+/+) control kidneys subjected to ischemia-reperfusion. However, ischemic injury resulted in a significant decrease in the intrarenal resident dendritic cell (DC; CD45(+)MHCII(+)CD11b(lo)F4/80(hi)) population in HO-1(-/-) kidneys compared with controls. Syngeneic transplant experiments utilizing green fluorescent protein-positive HO-1(+/+) or HO-1(-/-) donor kidneys and green fluorescent protein-negative HO-1(+/+) recipients confirmed increased migration of the resident DC population from HO-1(-/-) donor kidneys, compared to HO-1(+/+) donor kidneys, to the peripheral lymphoid organs. This effect on renal DC migration was corroborated in myeloid-specific HO-1(-/-) mice subjected to bilateral ischemia. These mice also displayed impaired renal recovery and increased fibrosis at day 7 after injury. These results highlight an important role for HO-1 in orchestrating the trafficking of myeloid cells in AKI, which may represent a key pathway for therapeutic intervention.

Objective Transcatheter aortic valve replacement (TAVR) has recently become a suitable alternative for treatment of symptomatic aortic stenosis in patients who are at very high risk for morbidity and mortality with conventional corrective surgery. In the fall of 2011, the Food and Drug Administration approved the use of TAVR, allowing for reimbursement at institutions outside of investigative trials. We report the initiation of a TAVR-based program at an academic tertiary care facility that did not participate in the Placement of Aortic Transcatheter Valves (PARTNER) 1 or PARTNER II trials. Methods A total of 160 patients were evaluated for TAVR from May 2012 through June 2013. Transcatheter aortic valve replacement was found to be appropriate for 50 (31%). Results In this experience, morbidity and mortality were similar to those reported for the PARTNER trial (30-day hospital mortality was 8%). A single case of presumed cerebrovascular accident was observed. These results demonstrate that the real-world application can be done with comparable results. Implementation of lessons learned in the trials allowed a very short learning curve and excellent results after only a limited number of patients. Use of computed tomography reconstructed images for operative planning, including fluoroscopic angle, facilitated minimal use of contrast in each case. Conclusions Transcatheter aortic valve replacement is a viable option for patients at very high risk for surgical intervention in the post-Food and Drug Administration approval era. Real-world results comparable with published outcomes from experienced centers involved in the PARTNER trial can be achieved.

Introduction: Inotrope use in decompensated congestive heart failure (CHF) is associated with improved hemodynamics, but did not improve outcomes in previous trials, with 50% 6-month mortality. However, many of these studies predated modern CHF therapies, including aldosterone antagonists, implantable cardioverter-defibrillators (ICDs), and resynchronization. We evaluated contemporary survival and outcomes on long-term inotropes in advanced CHF. Methods: We collected baseline and post-inotrope data on 197 consecutive patients discharged from our hospital between January 2007 and March 2013 on intravenous inotropes. Clinical, hemodynamic, catheterization, and survival data were collected. T-tests and Chi-square tests were used to compare outcomes, and Kaplan-Meier curves to evaluate survival. Results: Among the 197 patients, 25.8% were women, 40% had ischemic etiology and mean age was 54.4 years (standard deviation [SD] 14.6 years). Patients started on inotropes had CHF refractory to standard management, with mean baseline NYHA 3.7, cardiac index (CI) 1.7 L/min/m2, pulmonary capillary wedge pressure (PCWP) 25.6 mmHg, and left ventricular ejection fraction 17%. Milrinone was used in 85% and dobutamine in 15% of patients. Sixty-eight patients died, 24 were weaned off inotropes, 23 were transplanted, 32 received a LVAD, and 50 remained on inotropes. Mean NYHA class decreased from 3.7 to 2.7 (p Conclusions: Survival on long term-inotropes in this study was improved compared to previous reports. Routine ICD use may mitigate some arrhythmic risks of inotropes. Inotropes may be used as a bridge to initiate standard CHF therapy and subsequently weaned in selected cases.

Kidney allograft rejection is associated with infiltration of inflammatory CD11b+ leukocytes. A CD11b agonist leukadherin-1 (LA1) increases leukocyte adhesion, preventing their transmigration and tissue recruitment in vivo. Here, we test the extent to which LA1-mediated activation of CD11b/CD18 enhances kidney allograft survival in a mouse model of fully MHC-mismatched orthotopic kidney transplantation, where C57BL/6J (H-2(b)) recipients received kidney allografts from Balb/c mice (H-2(d)). Isograft control recipients received a kidney from a littermate. Control isograft and allograft recipients were treated daily with cyclosporine (CsA) for 2 weeks, while the test group received CsA therapy and daily LA1 injections during week 1 and alternate days during weeks 2-8. LA1 treatment reduced interstitial leukocyte infiltration in the allograft, reduced neointimal hyperplasia and glomerular damage, and prolonged graft survival from 48.5% (CsA only) to 100% (CsA and LA1) on day 60. Serum creatinine levels showed significantly improved kidney function in LA1-treated mice compared to CsA-treated allograft controls [0.52 ± 0.18 mg/dL vs 0.24 ± 0.07 mg/dL (n = 5), respectively]. Furthermore, combination therapy reduced macrophage infiltration and increased the frequency of FoxP3 + Tregs in the allograft. These findings indicate a crucial role for CD11b/CD18 in the control of leukocyte migration to the transplanted kidney and identify integrin agonist LA1 as a novel potential therapeutic agent for kidney transplantation.

Heart-lung transplantation (Tx) is known to offer a protective effect against acute cardiac rejection. This study was undertaken to evaluate acute and chronic heart and/or lung rejection in the setting of multiple-transplanted organs from the same donor compared with single-organ transplantation.Acute (treated rejection episodes of heart or lungs) and chronic (allograft vasculopathy in hearts and bronchiolitis obliterans syndrome [BOS] in lungs) rejection events were analyzed in 348 heart transplant (H) recipients, 24 heart-lung (HL) recipients, 82 double-lung (L) recipients and 8 heart-kidney (HK) recipients18 years of age, who were transplanted between 1990 and 2002.Survival at 3 years differed among groups as follows: HK, 100%; H, 82%; HL, 74%; and L, 70%. The probability of acute rejection within the first 3 months was higher in H recipients than in HL (81% vs 22%; p0.0001) or HK (81% vs 12%; p = 0.00009) recipients. Acute cardiac rejection occurred more frequently during the first 2 years in isolated H recipients compared with HL (2.8 vs 0.27 episodes; p0.0001) and HK (2.8 vs 0.54; p0.001) recipients. Acute lung rejection occurred more frequently in the first 2 years in L than HL (2.4 vs 1.0 episodes; p = 0.02) recipients. Chronic cardiac rejection (allograft vasculopathy) was more likely within 3 years after H compared with HL (32% vs 16%; p = 0.04) or HK (32% vs 0%; p = 0.14). The onset of chronic lung rejection (BOS) within 3 years was similar in HL and L recipients (39% vs 40%; p = 0.9).Recipients of multiple organs from a single donor undergo less acute rejection of the heart or lungs compared with isolated heart or lung transplant recipients. Cardiac allograft vasculopathy is decreased significantly when cardiac transplantation is combined with a lung allograft. A lower incidence of cardiac allograft vasculopathy is observed when cardiac transplantation is combined with a renal allograft, and may prove statistically significant when more cases have been accumulated. These phenomena may result from immune modulation of the recipient by simultaneous transplant of disparate tissues or introduction of immune-modulating hematopoietic elements.

The development of allograft vascular disease (AVD) may be related to altered expression of the fibrinolytic system. We determined the extent to which plasminogen activator inhibitor type 1 (PAI-1) expression in donor tissue influences intimal proliferation (IP) in a mouse model of AVD.We utilized an end-to-end abdominal aortic transplant model in mice to investigate the development of IP in 3 groups of 6 recipients. Group A (negative control) utilized C57BL/6J strain mice as both donors and recipients. In Groups B (positive control) and C, C57BL/6J mice were vessel donors and CBA/J mice were recipients. Both groups received intraperitoneal anti-CD4 and anti-CD8 monoclonal antibodies (250 microg/week for 5 weeks). Group C recipients, however, were transplanted with vessels from C57BL/6J PAI-1 knockout mice. Animals were killed at 50 days. Transplanted aortas were removed and intimal areas calculated using morphometric analysis.Group A (mean intimal area 6421 +/- 8507 microm(2)) demonstrated very little IP in comparison to the other groups. IP was significantly higher in Group B (mean intimal area 56357 +/- 35629 microm(2)) than Group A (p = 0.008). Group C (mean intimal area 288195 +/- 123279 microm(2)) demonstrated significantly more intimal proliferation than either Groups A or B (vs B, p = 0.003; vs A, p0.001). The significance of these results is maintained if intimal thickness is measured as a stand-alone reference for the intimal response.Lack of PAI-1 expression in donor tissue greatly exaggerates the extent of IP after allogeneic transplantation and suggests that PAI-1 is important in limiting the early phase of AVD.

Dilated cardiomyopathy and ventricular noncompaction have been reported in association with deletion 1p36 syndrome. Previous descriptions include echocardiographic and/or gross pathologic descriptions. There are no previous reports of microscopic findings. We report a case with descriptions of echocardiographic, gross pathologic, and microscopic findings.

Background— Inotrope use in heart failure treatment was associated with improved symptoms, but worse survival in clinical trials. However, these studies predated use of modern heart failure therapies. This study evaluates contemporary outcomes on long-term inotropes. Methods and Results— We collected baseline and postinotrope data on 197 patients discharged on inotropes between January 2007 and March 2013. Baseline characteristics, hemodynamic and clinical changes on inotropes, and survival were evaluated. Patients initiated on inotropes had refractory heart failure, with median baseline New York Heart Association class IV, cardiac index of 1.7 L/min per m 2 , pulmonary capillary wedge pressure of 25.6 mm Hg, and left ventricular ejection fraction of 18.7%. Inotropes were used in patients listed for transplant or scheduled for left ventricular assist device (LVAD; 60 patients), in patients being evaluated for LVAD/transplant (20 patients), for stabilization pending cardiac resynchronization therapy/percutaneous coronary intervention (4 patients), in patients who were offered LVAD but chose inotropes (15 patients), and for palliation (98 patients). Milrinone was used in 84.8% and dobutamine in 15.2%. At the end of the study, 68 patients had died, 24 were weaned off inotropes, 23 were transplanted, 32 received LVADs, and 50 remained on inotropes. Patients who received inotropes for palliation or those who preferred inotropes over LVAD had median survival of 9.0 months (interquartile range, 3.1–37.1 months), actuarial 1-year survival of 47.6%, and 2-year survival of 38.4%. Of 60 patients who were placed on inotropes as a bridge to transplant/LVAD, 55 were successfully maintained on inotropes until transplant/LVAD. Conclusions— Survival on inotropes for patients who are not candidates for transplant/LVAD is modestly better than previously reported, but remains poor. Inotropes are effective as a bridge to transplant/LVAD.

Multiple mechanisms may be involved in postoperative atrial fibrillation. Therefore, our objective was to determine the risk factors for postoperative atrial fibrillation as a function of time after coronary artery bypass grafting or valve surgeries to determine which risk factors might predominate at different times.Parametric hazard functions were determined for 1583 patients and then in subgroups (coronary artery bypass grafting alone, mitral valve procedure, and aortic valve replacement +/- coronary artery bypass grafting). Multivariable risk factor analyses were performed, and the risk for postoperative atrial fibrillation was estimated.The risk for postoperative atrial fibrillation for all patients was highest immediately postoperatively and at 48 hours. The initial peak risk declined to approximately zero within 18 hours postoperatively. A second peak occurred at 48 hours, followed by a slow decline over the following 4 to 7 days. The time intervals encompassing these peaks were termed phase I and phase II. Predominant risk factors in phase I were older age (relative risk [RR], 1.6; P = .006), longer crossclamp time (RR, 1.3; P = .001), and mitral valve procedure (RR, 2.5; P = .0001). In phase II, these were older age (RR, 3.0; P.0001), greater weight (RR, 1.6; P.0001), and Caucasian race (RR, 2.5; P = .006). For patients receiving a mitral valve procedure, the risk for postoperative atrial fibrillation in phase II was higher and remained elevated for as long as 9 days postoperatively in comparison with isolated coronary artery bypass grafting, for which the risk returned to near baseline by postoperative day 6.Phase I and phase II periods are associated with distinct risk factors; therefore, it is likely that the mechanisms of postoperative atrial fibrillation change over time.