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Obesity-associated increases in adipose tissue (AT) CD11c(+) cells suggest that dendritic cells (DC), which are involved in the tissue recruitment and activation of macrophages, may play a role in determining AT and liver immunophenotype in obesity. This study addressed this hypothesis. With the use of flow cytometry, electron microscopy, and loss-and-gain of function approaches, the contribution of DC to the pattern of immune cell alterations and recruitment in obesity was assessed. In AT and liver there was a substantial, high-fat diet (HFD)-induced increase in DC. In AT, these increases were associated with crown-like structures, whereas in liver the increase in DC constituted an early and reversible response to diet. Notably, mice lacking DC had reduced AT and liver macrophages, whereas DC replacement in DC-null mice increased liver and AT macrophage populations. Furthermore, delivery of bone marrow-derived DC to lean wild-type mice increased AT and liver macrophage infiltration. Finally, mice lacking DC were resistant to the weight gain and metabolic abnormalities of an HFD. Together, these data demonstrate that DC are elevated in obesity, promote macrophage infiltration of AT and liver, contribute to the determination of tissue immunophenotype, and play a role in systemic metabolic responses to an HFD. [ABSTRACT FROM AUTHOR]

The utility of troponin levels, including high sensitivity troponin T (hs-TnT), after orthotopic heart transplant (OHT) is controversial. Conflicting data exist regarding its use as a marker of acute rejection. Few studies have examined possible associations of hs-TnT levels immediately after OHT with metrics of intensive care unit (ICU) resource utilization or risk of acute rejection. We performed a retrospective cohort chart review including all OHT recipients < 20 years of age at our center between June 2019 and December 2022. Patients were divided into two groups based on supra- or sub-median initial hs-TnT levels (median 3462.5 ng/L). Primary outcome was days requiring ICU-level care, secondary outcomes included days intubated, days requiring positive pressure ventilation (PPV), days on inotropic medications, actual ICU length of stay, Vasoactive Inotrope Scores (VIS) on postoperative days (POD) 0 through 7, and acute rejection at 30 days and one year after OHT. Patients with higher hs-TnT required ICU level care for longer [13.5 (10-17.5) vs. 9.5 (8-12) days, p = 0.01] and spent more days intubated [6 (4-7) vs. 3 (3-5) days, p < 0.001], on PPV [9 (6-15) vs. 6 (5-8.5) days, p = 0.02], and on inotropes [11 (9-14) vs. 8 (7-11) days, p = 0.025]. VIS was only different between groups on POD7 [5 (3-7) vs. 3 (0-5), p = 0.04]. There was no difference in rejection between the groups. Higher hs-TnT immediately following pediatric OHT may predict higher ICU resource utilization, despite no difference in VIS, although it does not predict acute rejection in the first year after OHT., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Pediatric heart transplant patients are at greatest risk of allograft loss in the first year. We assessed whether machine learning could improve 1-year risk assessment using the Pediatric Heart Transplant Society database., Methods: Patients transplanted from 2010 to 2019 were included. The primary outcome was 1-year graft loss free survival. We developed a prediction model using cross-validation, by comparing Cox regression, gradient boosting, and random forests. The modeling strategy with the best discrimination and calibration was applied to fit a final prediction model. We used Shapley additive explanation (SHAP) values to perform variable selection and to estimate effect sizes and importance of individual variables when interpreting the final prediction model., Results: Cumulative incidence of graft loss or mortality was 7.6%. Random forests had favorable discrimination and calibration compared to Cox proportional hazards with a C-statistic (95% confidence interval [CI]) of 0.74 (0.72, 0.76) versus 0.71 (0.69, 0.73), and closer alignment between predicted and observed risk. SHAP values computed using the final prediction model indicated that the diagnosis of congenital heart disease (CHD) increased 1 year predicted risk of graft loss by 1.7 (i.e., from 7.6% to 9.3%), need for mechanical circulatory support increased predicted risk by 2, and single ventricle CHD increased predicted risk by 1.9. These three predictors, respectively, were also estimated to be the most important among the 15 predictors in the final model., Conclusions: Risk prediction models used to facilitate patient selection for pediatric heart transplant can be improved without loss of interpretability using machine learning., (© 2023 Wiley Periodicals LLC.)

Background: Patients after Fontan palliation represent a growing pediatric population requiring heart transplant (HTx) and often have lymphopenia (L) and/or hypogammaglobinemia that may be exacerbated by protein-losing enteropathy (PLE, P). The post-HTx effects of this altered immune phenotype are not well studied., Methods: In this study of the Pediatric Heart Transplant Society Registry, 106 Fontan patients who underwent HTx between 2005 and 2018 were analyzed. The impact of lymphopenia and PLE on graft survival, infection, rejection, and malignancy was analyzed at 1 and 5 years post-HTx., Results: The following combinations of lymphopenia and PLE were noted: +L+P, n = 37; +L-P, n = 23; -L+P, n = 10; and -L-P, n = 36. Graft survival between the groups was similar within the first year after transplant (+L+P: 86%, +L-P: 86%, -L+P: 87%, -L-P: 89%, p = .9). Freedom from first infection post-HTx was greatest among -L-P patients compared to patients with either PLE, lymphopenia, or both; with a 22.1% infection incidence in the -L-P group and 41.4% in all others. These patients had a significantly lower infection rate in the first year after HTx (+L+P: 1.03, +L-P: 1, -L+P: 1.3, -L-P: 0.3 infections/year, p < .001) and were similar to a non-single ventricle CHD control group (0.4 infections/year). Neither freedom from rejection nor freedom from malignancy 1 and 5 years post-HTx, differed among the groups., Conclusions: Fontan patients with altered immunophenotype, with lymphopenia and/or PLE, are at increased risk of infection post-HTx, although have similar early survival and freedom from rejection and malignancy. These data may encourage alternative immunosuppression strategies and enhanced monitoring for this growing subset of patients., (© 2022 Wiley Periodicals LLC.)

Introduction: Immune cell function assay (ICFA) and CD3 lymphocyte counts have been considered to be useful in discerning the overall intensity of immunosuppression in pediatric orthotopic heart transplant (OHT) recipients., Methods: The aim of this retrospective analysis was to evaluate trends of ICFA and CD3 lymphocyte counts and their association with adverse outcomes post-OHT., Results: A total of 381 ICFA and 493 CD3 laboratory values obtained in 78 patients within six months post-OHT were analyzed. There were 14 patients treated for biopsy-proven acute rejection, four of whom had ISHLT grade 2R/3A rejection. In patients with rejection versus those without, CD3 and ICFA values were 122 (IQR 74.5-308) cells/mm 2 and 224.5 (IQR 132-343.5) ng/ml compared to 231.8 (IQR 68-421) cells/m 2 and 191 (IQR 81.5-333) ng/mL (p = NS for both). Twenty-six patients had at least one detectable cytomegalovirus or Epstein-Barr virus DNAemia within the study timeframe. In patients with viremia versus those without, CD3 and ICFA values were 278.5 (IQR 68-552) cells/mm 2 and 130 (IQR 48-284) ng/ml compared to 195 (IQR 74.5-402.5) cells/mm 2 and 212 (IQR 89-342) ng/ml (p = NS for both)., Conclusions: No association was found between these immune markers and adverse outcomes. In the absence of larger pediatric studies justifying the role of these tests in identifying elevated risk profiles post OHT, we do not recommend their routine use., (© 2022 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Antibody mediated rejection (AMR) is an increasingly studied cause of graft failure after heart transplantation. AMR diagnosis previously required the detection of circulating donor specific antibodies (DSA); however, the most recent criteria only require pathological findings. This classification defined a subset of patients with AMR, yet without known antibodies. Here, we sought to evaluate differences in the transcriptome profile associated with different types of AMR., Methods: RNA sequencing was used on endomyocardial biopsies to analyze and compare transcriptomic profiles associated with different subtypes of AMR defined by immunopathological and histopathological findings, as well as the presence or absence of DSA. Gene expression profiles were characterized for each diagnostic group., Results: The most divergent gene expression profiles were observed between patients with or without DSA. AMR subtypes associated with DSA showed expression of signature genes involved in monocyte activation and response to interferon. There was also substantial difference between the transcriptomic profiles of AMR defined by histopathological and immunopathological findings, the latter being associated with expression of mucin genes. In contrast, there was no differential RNA expression between patients with pAMR1i without DSA and those without AMR. Likewise, no differential expression was observed between patients with pAMR1h with DSA and pAMR2., Conclusions: Overall, our studies reveal different expression profiles in endomyocardial biopsies in relation to some key criteria used to diagnose AMR. These findings support the view that the diagnosis of AMR encompasses several phenotypes that may rely on distinct mechanisms of injury., (Copyright © 2021 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

As the United States' original epicenter of the COVID-19 pandemic and one of the leading national paediatric heart failure/cardiomyopathy programs, we describe our experience with the spectrum of COVID-19 in the paediatric heart failure population.

Antibody-mediated rejection (AMR) driven by the development of donor-specific antibodies (DSA) directed against mismatched donor human leukocyte antigen (HLA) is a major risk factor for graft loss in cardiac transplantation. Recently, the relevance of non-HLA antibodies has become more prominent as AMR can be diagnosed in the absence of circulating DSA. Here, we assessed a single-center cohort of 64 orthotopic heart transplant recipients transplanted between 1994 and 2014. Serum collected from patients with ≥ pAMR1 (n = 43) and non-AMR (n = 21) were tested for reactivity against a panel of 44 non-HLA autoantigens. The AMR group had a significantly greater percentage of patients with elevated reactivity to autoantigens compared to non-AMR (P = .002) and healthy controls (n = 94, P < .0001). DSA-positive AMR patients exhibited greater reactivity to autoantigens compared to DSA-negative (P < .0001) and AMR patients with DSA and PRA > 10% were identified as the subgroup with significantly elevated responses. Reactivity to 4 antigens, vimentin, beta-tubulin, lamin A/C, and apolipoprotein L2, was significantly different between AMR and non-AMR patients. Moreover, increased reactivity to these antigens was associated with graft failure. These results suggest that antibodies to non-HLA are associated with DSA-positive AMR although their specific role in mediating allograft injury is not yet understood., (© 2020 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Objective: Overnutrition can alter gene expression patterns through epigenetic mechanisms that may persist through generations. However, it is less clear if overnutrition, for example a high fat diet, modifies epigenetic control of gene expression in adults, or by what molecular mechanisms, or if such mechanisms contribute to the pathology of the metabolic syndrome. Here we test the hypothesis that a high fat diet alters hepatic DNA methylation, transcription and gene expression patterns, and explore the contribution of such changes to the pathophysiology of obesity., Methods: RNA-seq and targeted high-throughput bisulfite DNA sequencing were used to undertake a systematic analysis of the hepatic response to a high fat diet. RT-PCR, chromatin immunoprecipitation and in vivo knockdown of an identified driver gene, Phlda1 , were used to validate the results., Results: A high fat diet resulted in the hypermethylation and decreased transcription and expression of Phlda1 and several other genes. A subnetwork of genes associated with Phlda1 was identified from an existing Bayesian gene network that contained numerous hepatic regulatory genes involved in lipid and body weight homeostasis. Hepatic-specific depletion of Phlda1 in mice decreased expression of the genes in the subnetwork, and led to increased oil droplet size in standard chow-fed mice, an early indicator of steatosis, validating the contribution of this gene to the phenotype., Conclusions: We conclude that a high fat diet alters the epigenetics and transcriptional activity of key hepatic genes controlling lipid homeostasis, contributing to the pathophysiology of obesity.

Mitochondrial dysfunction is associated with many human diseases and results from mismatch of damage and repair over the life of the organelle. PARK2 is a ubiquitin E3 ligase that regulates mitophagy, a repair mechanism that selectively degrades damaged mitochondria. Deletion of PARK2 in multiple in vivo models results in susceptibility to stress-induced mitochondrial and cellular dysfunction. Surprisingly, Park2 knockout (KO) mice are protected from nutritional stress and do not develop obesity, hepatic steatosis or insulin resistance when fed a high-fat diet (HFD). However, these phenomena are casually related and the physiological basis for this phenotype is unknown. We therefore undertook a series of acute HFD studies to more completely understand the physiology of Park2 KO during nutritional stress. We find that intestinal lipid absorption is impaired in Park2 KO mice as evidenced by increased fecal lipids and reduced plasma triglycerides after intragastric fat challenge. Park2 KO mice developed hepatic steatosis in response to intravenous lipid infusion as well as during incubation of primary hepatocytes with fatty acids, suggesting that hepatic protection from nutritional stress was secondary to changes in energy balance due to altered intestinal triglyceride absorption. Park2 KO mice showed reduced adiposity after 1-wk HFD, as well as improved hepatic and peripheral insulin sensitivity. These studies suggest that changes in intestinal lipid absorption may play a primary role in protection from nutritional stress in Park2 KO mice by preventing HFD-induced weight gain and highlight the need for tissue-specific models to address the role of PARK2 during metabolic stress., (Copyright © 2016 the American Physiological Society.)

The contribution of natural killer T (NKT) cells to the pathogenesis of metabolic abnormalities of obesity is controversial. While the combined genetic deletion of NKT and CD8(+) T-cells improves glucose tolerance and reduces inflammation, interpretation of these data have been complicated by the recent observation that the deletion of CD8(+) T-cells alone reduces obesity-induced inflammation and metabolic dysregulation, leaving the issue of the metabolic effects of NKT cell depletion unresolved. To address this question, CD1d null mice (CD1d(-/-)), which lack NKT cells but have a full complement of CD8(+) T-cells, and littermate wild type controls (WT) on a pure C57BL/6J background were exposed to a high fat diet, and glucose intolerance, insulin resistance, dyslipidemia, inflammation, and obesity were assessed. Food intake (15.5±4.3 vs 15.3±1.8 kcal/mouse/day), weight gain (21.8±1.8 vs 22.8±1.4 g) and fat mass (18.6±1.9 vs 19.5±2.1 g) were similar in CD1d(-/-) and WT, respectively. As would be expected from these data, metabolic rate (3.0±0.1 vs 2.9±0.2 ml O(2)/g/h) and activity (21.6±4.3 vs 18.5±2.6 beam breaks/min) were unchanged by NKT cell depletion. Furthermore, the degree of insulin resistance, glucose intolerance, liver steatosis, and adipose and liver inflammatory marker expression (TNFα, IL-6, IL-10, IFN-γ, MCP-1, MIP1α) induced by high fat feeding in CD1d(-/-) were not different from WT. We conclude that deletion of NKT cells, in the absence of alterations in the CD8(+) T-cell population, is insufficient to protect against the development of the metabolic abnormalities of diet-induced obesity.

The pathophysiology underlying mitochondrial dysfunction in insulin-resistant skeletal muscle is incompletely characterized. To further delineate this we investigated the interaction between insulin signaling, mitochondrial regulation, and function in C2C12 myotubes and in skeletal muscle. In myotubes elevated insulin and glucose disrupt insulin signaling, mitochondrial biogenesis, and mitochondrial bioenergetics. The insulin-sensitizing thiazolidinedione pioglitazone restores these perturbations in parallel with induction of the mitochondrial biogenesis regulator PGC-1alpha. Overexpression of PGC-1alpha rescues insulin signaling and mitochondrial bioenergetics, and its silencing concordantly disrupts insulin signaling and mitochondrial bioenergetics. In primary skeletal myoblasts pioglitazone also up-regulates PGC-1alpha expression and restores the insulin-resistant mitochondrial bioenergetic profile. In parallel, pioglitazone up-regulates PGC-1alpha in db/db mouse skeletal muscle. Interestingly, the small interfering RNA knockdown of the insulin receptor in C2C12 myotubes down-regulates PGC-1alpha and attenuates mitochondrial bioenergetics. Concordantly, mitochondrial bioenergetics are blunted in insulin receptor knock-out mouse-derived skeletal myoblasts. Taken together these data demonstrate that elevated glucose and insulin impairs and pioglitazone restores skeletal myotube insulin signaling, mitochondrial regulation, and bioenergetics. Pioglitazone functions in part via the induction of PGC-1alpha. Moreover, PGC-1alpha is identified as a bidirectional regulatory link integrating insulin-signaling and mitochondrial homeostasis in skeletal muscle.

Nonalcoholic fatty liver disease (NAFLD), hypertriglyceridemia, and elevated free fatty acids are present in the majority of patients with metabolic syndrome and type 2 diabetes mellitus and are strongly associated with hepatic insulin resistance. In the current study, we tested the hypothesis that an increased rate of fatty acid oxidation in liver would prevent the potentially harmful effects of fatty acid elevation, including hepatic triglyceride (TG) accumulation and elevated TG secretion. Primary rat hepatocytes were transduced with adenovirus encoding carnitine palmitoyltransferase 1a (Adv-CPT-1a) or control adenoviruses encoding either beta-galactosidase (Adv-beta-gal) or carnitine palmitoyltransferase 2 (Adv-CPT-2). Overexpression of CPT-1a increased the rate of beta-oxidation and ketogenesis by approximately 70%, whereas esterification of exogenous fatty acids and de novo lipogenesis were unchanged. Importantly, CPT-1a overexpression was accompanied by a 35% reduction in TG accumulation and a 60% decrease in TG secretion by hepatocytes. There were no changes in secretion of apolipoprotein B (apoB), suggesting the synthesis of smaller, less atherogenic VLDL particles. To evaluate the effect of increasing hepatic CPT-1a activity in vivo, we injected lean or obese male rats with Adv-CPT-1a, Adv-beta-gal, or Adv-CPT-2. Hepatic CPT-1a activity was increased by approximately 46%, and the rate of fatty acid oxidation was increased by approximately 44% in lean and approximately 36% in obese CPT-1a-overexpressing animals compared with Adv-CPT-2- or Adv-beta-gal-treated rats. Similar to observations in vitro, liver TG content was reduced by approximately 37% (lean) and approximately 69% (obese) by this in vivo intervention. We conclude that a moderate stimulation of fatty acid oxidation achieved by an increase in CPT-1a activity is sufficient to substantially reduce hepatic TG accumulation both in vitro and in vivo. Therefore, interventions that increase CPT-1a activity could have potential benefits in the treatment of NAFLD.

Objective: To test the antitumour effect of gonadotrophin releasing-hormone (GnRH) analogues in women with recurrent endometrial cancer., Design: An open phase II observational trial of GnRH analogues. Serial measurements of gonadotrophins, sex hormones and tumour dimensions were made together with repeat biopsy when possible to assess the response to treatment., Setting: The outpatient clinics of the Department of Medical Oncology at The Royal London, Royal Marsden and St Bartholomew's hospitals., Subjects: 17 patients with endometrial cancer which had recurred after surgery, radiotherapy and progesterone treatment and was symptomatic, progressive and assessable for response., Intervention: Monthly subcutaneous injection of GnRH analogue., Main Outcome Measures: Reduction in serum gonadotrophins and reduction in tumour dimensions., Results: Six out of 17 patients (35%, 95% CI 12.6-58%) achieved a complete or partial remission which continues for a median of 20 months with no adverse effects., Conclusion: GnRH analogues have a significant antitumour effect in recurrent endometrial cancer which warrants further examination in comparison with progestogens.

Rapidly recurrent symptoms of airways obstruction by tumour may require repeated radiotherapy or endoscopic laser treatment--but these procedures may themselves be distressing. Use of a novel coated metal stent may reduce the frequency with which such palliative intervention is required.

A patient with a carcinosarcoma of the Fallopian tube is presented. She is the first reported from the United Kingdom and the 23rd in the literature. The clinical and pathological features, pathogenesis and management are discussed.

Seven hundred and four patients with bladder cancer treated by radiotherapy at the London Hospital between 1965 and 1974 have been followed for a minimum period of 5 years. Invasive tumours were usually treated by radical radiotherapy. Cystectomy was reserved for patients whose tumours did not respond to radiation, recurred later on, or who developed complications from radiotherapy. The crude 5-year survival rate for T3 tumours in this series was 38%--similar to that obtained in other centres using pre-operative radiation followed by cystectomy, but this overall figure conceals the important difference between 2 distinct tumour populations. Nearly half of these tumours appear to be radiosensitive, giving a 56% crude 5-year survival rate for T3 tumours. The remainder are radioinsensitive, with only a 17% crude 5-year survival rate for T3 tumours. When there is a good initial response to radiotherapy there would seem to be no necessity to insist upon cystectomy.

Advanced breast carcinoma responds to tamoxifen in more than 30% of cases (Mouridsen et al., 1978). It is widely used for hormonal treatment in women suffering from breast carcinoma, particularly if they are post-menopausal (Carter, Bakowski and Hellmann, 1981).

A stereotactically implanted afterloaded system for the interstitial radiotherapy of brain tumours is described. The technique has the advantages of accuracy of dosimetry, no radiation hazard in the operating theatre and ease of afterloading with a source which may be inserted and removed at will. Caesium-137 is used, but the system could equally well be used with other isotopes.

The time spent in hospital when cerebral metastases occur as the first site of relapse in patients with small cell carcinoma of the lung (SCCL) has been analysed and compared to the consequences of relapse in the liver. In the course of a clinical trial with 370 patients, 50 patients relapsed initially in the brain and 20 in the liver. The 2 groups were comparable with respect to performance status at diagnosis and the amount of home support available. Patients who relapsed in the brain suffered a greater deterioration in performance status, and spent a greater proportion of their remaining life in hospital than did patients whose initial relapse was in the liver. This difference was most marked in patients who died soon after relapse. Radiotherapy (20 Gy in 5 fractions over one week or 30 Gy in 10 fractions over 2 weeks) and dexamethasone were not very effective treatments for brain relapse though subjective responses were common. The substantial morbidity and lengthy hospitalisation resulting from brain relapse compared with relapse at another site is a important factor to be considered in assessing whether prophylactic cranial irradiation should routinely be offered to patients with SCCL.

Three hundred and seventy one patients with extensive or limited small cell cancer of the lung took part in a randomised trial to evaluate irradiation of the primary tumour in patients treated with combination chemotherapy. They were randomly allocated to treatment either with chemotherapy alone (198) or with both chemotherapy and radiotherapy (173). All 371 initially received 12 weeks of chemotherapy after which they were categorised according to response. Only those with stable or responding disease continued with their allotted treatment. Thus 144 received chemotherapy alone and 135 received both chemotherapy and radiotherapy. The design of the study permitted analysis of the effect of radiotherapy according to initial extent of disease and quality of early response to chemotherapy. Radiotherapy (40 Gy (4000 rad), one fraction a day over 20 days) did not improve the survival of patients in any category of initial extent of disease or early response to chemotherapy and was not effective in preventing local relapse.

Palliative treatment by radiotherapy was attempted in 17 cases of dysphagia, due to inoperable gastric carcinoma. Thirteen experienced a useful improvement in swallowing. Radiotherapy, using a moderate dose of radiation, is suggested as an alternative to intubation in such patients.

The Curietron is a remotely controlled afterloading machine for gynaecological low dose rate intracavitary radiotherapy. The Curietron and its installation are described together with specially designed applicators intended to produce a source geometry similar to the Manchester configuration. Some of the practical problems met are discussed. The principal value of the Curietron lies in the marked reduction of radiation exposure to all staff concerned.

A patient who developed a partial relapse of Bell's palsy following superficial radiotherapy to a basal cell carcinoma in the temple is reported. Nerves injured by Bell's palsy may be more susceptible to radiation induced damage.