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Arun Sivananthan1,2 *, Victoria Nicholas3 *, Georgina Kerry,4 Christopher Harlow,5 Pratyasha Saha,6 Helen-Cara Younan,7 Stephanie Williams,8 Lewis David,9 Clifford Lisk,10 Louise Schofield11 1Institute of Global Health Innovation, Imperial College London, London, UK; 2Department of Gastroenterology, Imperial College Healthcare NHS Trust, London, UK; 3Department of Medicine, Chelsea and Westminster NHS Foundation Trust, London, UK; 4Department of Gastroenterology, St George’s University Hospital NHS Foundation Trust, London, UK; 5Department of Cardiology, Epsom and St Heliers University Hospital, London, UK; 6Department of Rheumatology, University College London NHS Trust, London, UK; 7Department of Intensive Care Medicine, Imperial College Healthcare NHS Trust, London, UK; 8Department of Acute Medicine, Royal Free NHS Trust, London, UK; 9Department of Endocrinology, Bart’s Health NHS Trust, London, UK; 10Department of Geriatrics, Royal Free NHS Trust, London, UK; 11Department of Palliative Medicine, Royal Free NHS Trust, London, UK*These authors contributed equally to this workCorrespondence: Arun Sivananthan, Institute of Global Health Innovation Imperial College London, 10th Floor QEQM Building, London, W2 1NY, UK, Tel +44 0203 3126666, Email a.sivananthan@nhs.netIntroduction: The Covid-19 pandemic brought significant disruption to post-graduate medical education. Lecture-based training days were rapidly converted to webinars. This study aims to assess the perceptions of digital training in internal medical trainees.Methods: IMTs (internal medicine trainees) nationally were surveyed on their perceptions of digital training, ease of access, engagement, and interactivity via a 10-item questionnaire. A mixed-method approach using qualitative and quantitative questions was used. Likert scales were analysed using a mean result of above 3 to indicate agreement.Results: 359 trainees responded. Trainees agreed that they preferred digital training to face-to-face teaching (mean 3.68); digital training was more engaging (mean 4.25), easier to access (mean 4.49), and as effective for learning as face-to-face teaching (mean 4.69). The most reported advantages were no travel (89%) and the ability to watch later on (88%). 63% of trainees reported loss of social interaction as a disadvantage.Discussion: This survey suggests that digital teaching has a potential role in IMT training beyond the pandemic.Keywords: medical education, digital training, IMT, webinar, post-graduate training

Presents abstracts of communications to the British Geriatrics Society Spring Meeting held in April 2004. They include "HIV in Older Age," and "First Progress Report of the Hypertension in the Very Elderly Trial (HYVET)."

Presents an abstract of the study "Uptake of the Influenza Vaccine Amongst an Acute General Medicine Inpatient Population," by C. Lisk, I. Chemmanam and N. Stanley.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency affects 500 million people globally, impacting red blood cell (RBC) antioxidant pathways and increasing susceptibility to hemolysis under oxidative stress. Despite the systemic generation of reactive oxygen species during exercise, the effects of exercise on individuals with G6PD deficiency remain poorly understood This study utilized humanized mouse models expressing the G6PD Mediterranean variant (S188F, with 10% enzymatic activity) to investigate exercise performance and molecular outcomes. Surprisingly, despite decreased enzyme activity, G6PD-deficient mice have faster critical speed (CS) compared to mice expressing human canonical G6PD. Post-exercise, deficient mice did not exhibit differences in RBC morphology or hemolysis, but had improved cardiac function, including cardiac output, stroke volume, sarcomere length and mitochondrial content. Proteomics analyses of cardiac and skeletal muscles (gastrocnemius, soleus) from G6PD deficient compared to sufficient mice revealed improvements in mitochondrial function and increased protein turnover via ubiquitination, especially for mitochondrial and structural myofibrillar proteins. Mass spectrometry-based metabolomics revealed alterations in energy metabolism and fatty acid oxidation. These findings challenge the traditional assumptions regarding hemolytic risk during exercise in G6PD deficiency, suggesting a potential metabolic advantage in exercise performance for individuals carrying non-canonical G6PD variants., (Copyright © 2024 American Society of Hematology.)

Administration of oxygen microbubbles (OMBs) has been shown to increase oxygen and decrease carbon dioxide in systemic circulation, as well as reduce lung inflammation and promote survival in preclinical models of hypoxia caused by lung injury. However, their impact on microenvironmental oxygenation remains unexplored. Herein, we investigated the effects of intraperitoneal administration of OMBs in anesthetized rats exposed to hypoxic ventilation (FiO 2 = 0.14). Blood oxygenation and hemodynamics were evaluated over a 2 h time frame, and then organ and tissue samples were collected for hypoxic and metabolic analyses. Data showed that OMBs improved blood SaO 2 (~14%) and alleviated tissue hypoxia within the microenvironment of the kidney and intestine at 2 h of hypoxia. Metabolomic analysis revealed OMBs induced metabolic differences in the cecum, liver, kidney, heart, red blood cells and plasma. Within the spleen and lung, principal component analysis showed a metabolic phenotype more comparable to the normoxic group than the hypoxic group. In the spleen, this shift was characterized by reduced levels of fatty acids and 2-hydroxygluterate, alongside increased expression of antioxidant enzymes such as glutathione and hypoxanthine. Interestingly, there was also a shuttle effect within the metabolism of the spleen from the tricarboxylic acid cycle to the glycolysis and pentose phosphate pathways. In the lung, metabolomic analysis revealed upregulation of phosphatidylethanolamine and phosphatidylcholine synthesis, indicating a potential indirect mechanism through which OMB administration may improve lung surfactant secretion and prevent alveolar collapse. In addition, cell-protective purine salvage was increased within the lung. In summary, oxygenation with intraperitoneal OMBs improves systemic blood and local tissue oxygenation, thereby shifting metabolomic profiles of the lung and spleen toward a healthier normoxic state.

The purpose of this secondary qualitative analysis was to explore the play interactions of children with autism ( n = 10) and their pets in the home environment. Researchers coded 115 minutes of video of children playing with their pets at home and transcripts from eight caregiver interviews. Thematic analysis revealed six codes which represented three themes, including children with ASD play with pets in a variety of ways, playing with pets supports child development , and playing with pets yields benefits for children with ASD . Findings suggest playing with pets may be beneficial for developing responsibility and social skills of children with ASD, particularly in how they interact with animals. Future research should examine perspectives of families who do not own or who have relinquished pets and perspectives of adults with ASD to better understand positive and negative aspects of pet play., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Sickle cell disease and β-thalassemia represent hemoglobinopathies arising from dysfunctional or underproduced β-globin chains, respectively. In both diseases, red blood cell injury and anemia are the impetus for end organ injury. Because persistent erythrophagocytosis is a hallmark of these genetic maladies, it is critical to understand how macrophage phenotype polarizations in tissue compartments can inform on disease progression. Murine models of sickle cell disease and β-thalassemia allow for a basic understanding of the mechanisms and provide for translation to human disease. A multi-omics approach to understanding the macrophage metabolism and protein changes in two murine models of β-globinopathy was performed on peripheral blood mononuclear cells as well as spleen and liver macrophages isolated from Berkley sickle cell disease (Berk-ss) and heterozygous B1/B2 globin gene deletion (Hbb th3/+ ) mice. The results from these experiments revealed that the metabolome and proteome of macrophages are polarized to a distinct phenotype in Berk-ss and Hbb th3/+ compared with each other and their common-background mice (C57BL6/J). Further, spleen and liver macrophages revealed distinct disease-specific phenotypes, suggesting that macrophages become differentially polarized and reprogrammed within tissue compartments. We conclude that tissue recruitment, polarization, and metabolic and proteomic reprogramming of macrophages in Berk-ss and Hbb th3/+ mice may be relevant to disease progression in other tissue.

Introduction: Human and murine sickle cell disease (SCD) associated pulmonary hypertension (PH) is defined by hemolysis, nitric oxide depletion, inflammation, and thrombosis. Further, hemoglobin (Hb), heme, and iron accumulation are consistently observed in pulmonary adventitial macrophages at autopsy and in hypoxia driven rodent models of SCD, which show distribution of ferric and ferrous Hb as well as HO-1 and ferritin heavy chain. The anatomic localization of these macrophages is consistent with areas of significant vascular remodeling. However, their contributions toward progressive disease may include unique, but also common mechanisms, that overlap with idiopathic and other forms of pulmonary hypertension. These processes likely extend to the vasculature of other organs that are consistently impaired in advanced SCD., Methods: To date, limited information is available on the metabolism of macrophages or monocytes isolated from lung, spleen, and peripheral blood in humans or murine models of SCD., Results: Here we hypothesize that metabolism of macrophages and monocytes isolated from this triad of tissue differs between Berkley SCD mice exposed for ten weeks to moderate hypobaric hypoxia (simulated 8,000 ft, 15.4% O2) or normoxia (Denver altitude, 5000 ft) with normoxia exposed wild type mice evaluated as controls., Discussion: This study represents an initial set of data that describes the metabolism in monocytes and macrophages isolated from moderately hypoxic SCD mice peripheral lung, spleen, and blood mononuclear cells., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Lisk, Cendali, Pak, Swindle, Hassell, Nuss, George, Davizon-Castillo, Buehler, D’Alessandro and Irwin.)

Introduction: Exercise intolerance is a common clinical manifestation in patients with sickle cell disease (SCD), though the mechanisms are incompletely understood. Methods: Here we leverage a murine mouse model of sickle cell disease, the Berkeley mouse, to characterize response to exercise via determination of critical speed (CS), a functional measurement of mouse running speed upon exerting to exhaustion. Results: Upon observing a wide distribution in critical speed phenotypes, we systematically determined metabolic aberrations in plasma and organs-including heart, kidney, liver, lung, and spleen-from mice ranked based on critical speed performances (top vs. bottom 25%). Results indicated clear signatures of systemic and organ-specific alterations in carboxylic acids, sphingosine 1-phosphate and acylcarnitine metabolism. Metabolites in these pathways showed significant correlations with critical speed across all matrices. Findings from murine models were thus further validated in 433 sickle cell disease patients (SS genotype). Metabolomics analyses of plasma from 281 subjects in this cohort (with HbA < 10% to decrease confounding effects of recent transfusion events) were used to identify metabolic correlates to sub-maximal exercise test performances, as measure by 6 min walking test in this clinical cohort. Results confirmed strong correlation between test performances and dysregulated levels of circulating carboxylic acids (especially succinate) and sphingosine 1-phosphate. Discussion: We identified novel circulating metabolic markers of exercise intolerance in mouse models of sickle cell disease and sickle cell patients., Competing Interests: The authors declare that AD’A and TN are founders of Omix Technologies Inc. AD’A is an advisory board member of Macopharma and Hemanext Inc. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Cendali, Nemkov, Lisk, Lacroix, Nouraie, Zhang, Gordeuk, Buehler, Irwin and D’Alessandro.)

Aberrant coagulation in sickle cell disease (SCD) is linked to extracellular vesicle (EV) exposure. However, there is no consensus on the contributions of small EVs (SEVs) and large EVs (LEVs) toward underlying coagulopathy or on their molecular cargo. The present observational study compared the thrombin potential of SEVs and LEVs isolated from the plasma of stable pediatric and adult SCD patients. Further, EV lipid and protein contents were analyzed to define markers consistent with activation of thrombin and markers of underlying coagulopathy. Results suggested that LEVs-but not SEVs-from pediatrics and adults similarly enhanced phosphatidylserine (PS)-dependent thrombin generation, and cell membrane procoagulant PS (18:0;20:4 and 18:0;18:1) were the most abundant lipids found in LEVs. Further, LEVs showed activated coagulation in protein pathway analyses, while SEVs demonstrated high levels of cholesterol esters and a protein pathway analysis that identified complement factors and inflammation. We suggest that thrombin potential of EVs from both stable pediatric and adult SCD patients is similarly dependent on size and show lipid and protein contents that identify underlying markers of coagulation and inflammation.

Background: Previous studies have identified disparities in readmissions among Medicare beneficiaries hospitalized for the Hospital Readmissions Reduction Program's (HRRP's) priority conditions. Evidence suggests timely follow-up is associated with reduced risk of readmission, but it is unknown whether timely follow-up reduces disparities in readmission., Objective: To assess whether follow-up within 7 days after discharge from a hospitalization reduces risk of readmission and mitigates identified readmission disparities., Design: A retrospective cohort study using Cox proportional hazards models to estimate the associations between sociodemographic characteristics (race and ethnicity, dual-eligibility status, rurality, and area social deprivation), follow-up, and readmission. Mediation analysis was used to examine if disparities in readmission were mitigated by follow-up., Participants: We analyzed data from 749,402 Medicare fee-for-service beneficiaries hospitalized for acute myocardial infarction, chronic obstructive pulmonary disease, heart failure, or pneumonia, and discharged home between January 1 and December 1, 2018., Main Measure: All-cause unplanned readmission within 30 days after discharge., Key Results: Post-discharge follow-up within 7 days of discharge was associated with a substantially lower risk of readmission (HR: 0.52, 95% CI: 0.52-0.53). Across all four HRRP conditions, beneficiaries with dual eligibility and beneficiaries living in areas with high social deprivation had a higher risk of readmission. Non-Hispanic Black beneficiaries had higher risk of readmission after hospitalization for pneumonia relative to non-Hispanic Whites. Mediation analysis suggested that 7-day follow-up mediated 21.2% of the disparity in the risk of readmission between dually and non-dually eligible beneficiaries and 50.7% of the disparity in the risk of readmission between beneficiaries living in areas with the highest and lowest social deprivation. Analysis suggested that after hospitalization for pneumonia, 7-day follow-up mediated nearly all (97.5%) of the increased risk of readmission between non-Hispanic Black and non-Hispanic White beneficiaries., Conclusions: Improving rates of follow-up could be a strategy to reduce readmissions for all beneficiaries and reduce disparities in readmission based on sociodemographic characteristics., (© 2022. The Author(s) under exclusive licence to Society of General Internal Medicine.)

Vaccines have played a pivotal role in improving public health, however, many infectious diseases lack an effective vaccine. Controlling the spread of infectious diseases requires continuing studies to develop new and improved vaccines. Our laboratory has been investigating the immune enhancing mechanisms of Toll-like receptor (TLR) ligand-based adjuvants, including the TLR2 ligand Neisseria meningitidis outer membrane protein, PorB. Adjuvant use of PorB increases costimulatory factors on antigen presenting cells (APC), increases antigen specific antibody production, and cytokine producing T cells. We have demonstrated that macrophage expression of MyD88 (required for TLR2 signaling) is an absolute requirement for the improved antibody response induced by PorB. Here-in, we specifically investigated the role of subcapsular CD169+ marginal zone macrophages in antibody production induced by the use of TLR-ligand based adjuvants (PorB and CpG) and non-TLR-ligand adjuvants (aluminum salts). CD169 knockout mice and mice treated with low dose clodronate treated animals (which only remove marginal zone macrophages), were used to investigate the role of these macrophages in adjuvant-dependent antibody production. In both sets of mice, total antigen specific immunoglobulins (IgGs) were diminished regardless of adjuvant used. However, the greatest reduction was seen with the use of TLR ligands as adjuvants. In addition, the effect of the absence of CD169+ macrophages on adjuvant induced antigen and antigen presenting cell trafficking to the lymph nodes was examined using immunofluorescence by determining the relative extent of antigen loading on dendritic cells (DCs) and antigen deposition on follicular dendritic cells (FDC). Interestingly, only vaccine preparations containing PorB had significant decreases in antigen deposition in lymphoid follicles and germinal centers in CD169 knockout mice or mice treated with low dose clodronate as compared to wildtype controls. Mice immunized with CpG containing preparations demonstrated decreased FDC networks in the mice treated with low dose clodronate. Conversely, alum containing preparations only demonstrated significant decreases in IgG in CD169 knockout mice. These studies stress that importance of subcapsular macrophages and their unique role in adjuvant-mediated antibody production, potentially due to an effect of these adjuvants on antigen trafficking to the lymph node and deposition on follicular dendritic cells., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Lisk, Yuen, Kuniholm, Antos, Reiser and Wetzler.)

Introduction: The COVID-19 pandemic has been unsurpassed in clinical severity or infectivity since the 1918 Spanish influenza pandemic and continues to impact the world. During the A/H1N1 pandemic, healthcare workers presented concerns regarding their own and their families' health, as well as high levels of psychological distress. We aim to assess hospital trainees' concerns, perceived sufficiency of information, behaviour and reported psychological health during the COVID-19 pandemic., Design: Single 39-point questionnaire., Setting: A large NHS foundation trust in London., Participants: 204 hospital trainee doctors., Results: 204 trainees participated, of whom 91.7% (n=187) looked after COVID-19 patients. 91.6% (n=164) were worried about COVID-19; the most frequent concern was that of family and friends dying from COVID-19 (74.6%, n=126). 22.2% (n=36) reported being infected with COVID-19. 6.8% (n=11) of trainees considered avoiding going to work. Perceived sufficiency of information about COVID-19 was moderately high. 25.9% (n=42) reported social distancing at work compared with 94.4% (n=152) outside work. 98.2% (n=159) reported using PPE and 24.7% (n=40) were confident the provided PPE protected them. 41.9% (n=67) reported their psychological health had been adversely affected. 95.6% (n=153) supported provision of psychological support services and 62.5% (n=100) stated they would consider using them., Conclusions: A significant proportion of hospital trainees expressed worries about COVID-19, above all with regards to the wellbeing of their loved ones over their own. Confidence in sufficiency of provided information was high and in utilised infection control measures low. A larger proportion of trainees reported psychological as compared with physical health concerns, with a smaller proportion confirming having been infected with COVID-19 although most perceived their risk of infection as high. Seeking solutions to support hospital trainees in their duties and their wellbeing with their input would help to empower them and improve their health and morale while working during pandemics.

Vaccines are arguably one of the greatest advancements in modern medicine. Subunit vaccines comprise the majority of current preparations and consist of two main components-antigen and adjuvant. The antigen is a small molecule against which the vaccine induces an immune response to provide protection via the immunostimulatory ability of the adjuvant. Our laboratory has investigated the adjuvant properties of Toll-like receptor (TLR) ligand-based adjuvants, especially the outer membrane protein from Neisseria mengingitidis , PorB. In this current study we used PorB, along with CpG, an intracellular TLR9 agonist, and a non-TLR adjuvant, aluminum salts (Alum), to further investigate cellular mechanisms of adjuvanticity, focusing on the fate of intact antigen in the germinal center and association with follicular dendritic cells (FDCs). FDCs are located in the B cell light zone of the germinal center and are imperative for affinity maturation. They are stromal cells that retain whole intact antigen allowing recognition by the B cell receptor of the germinal center B cells. Our studies demonstrate that TLR ligands, but not Alum, increase the FDC network, while PorB and Alum increased colocalization of FDC and the model soluble antigen, ovalbumin (OVA). As PorB is the only adjuvant tested that induces both a higher number of FDCs and increased deposition of antigen on FDCs, it has the greatest ability to increase FDC-antigen interaction, essential for induction of B cell affinity maturation. These studies demonstrate a further mechanism and potential superiority of PorB as an adjuvant and its influence on antibody production., (Copyright © 2020 Lisk, Yuen, Kuniholm, Antos, Reiser and Wetzler.)

Our laboratory has focused on Porin B (PorB), an outer membrane protein from Neisseria meningitidis and TLR2 ligand-based adjuvant, to characterize specific molecular and cellular pathways involved in improved immune responses induced by vaccine adjuvants. PorB's ability to form micellar nanoparticular multi-molecular organized structures and its interaction with Toll-like receptor 2/1 complexes likely accounts for its potent adjuvant activity. Downstream from this stimulation, we have observed enhanced antigen uptake in antigen presenting cells (APC), greater antigen deposition in secondary lymphoid organs, and promotion of germinal center reactions. In mice, antigen-specific IgGs were increased after PorB adjuvanted vaccination using the model antigen ovalbumin (OVA). Likewise, this formulation resulted in more IL-4 and IFN-γ positive T cells. Mice that received PorB adjuvanted vaccinations benefitted from lower bacterial burdens when challenged with recombinant Listeria monocytogenes expressing OVA. Mouse models lacking MyD88 signaling in various APC types helped identify macrophages as an essential cell type for the adjuvant activity of PorB. We believe the work presented here provides examples of the mechanistic studies required to understand how vaccine adjuvants are contributing to the establishment of protective immunity.

TOLL-like receptor (TLR) ligands activate both innate and adaptive immune cells, while modulating the cellular immune response. The outer membrane protein (OMP) from Neisseria meninigitidis, PorB, is a naturally occurring TLR2 ligand and functions as an adjuvant. Here, we demonstrate that PorB increases the level of OVA in the endo-/lysosomal cellular compartment of BMDCs, increases antigen presenting cell (APC) trafficking to draining lymph nodes, and enhances antigen cross-presentation. PorB is capable of mounting an antigen specific T cell response by efficiently stimulating antigen cross-presentation in vivo and in vitro assessed by BMDC OT-I cocultivation assays. The enhanced antigen cross-presentation and the increased APC recruitment to secondary lymphoid tissues expand the scope of known adjuvant effects of PorB on the immune system. Our findings lead to a better understanding of how TLR-ligand based adjuvants can alter and modulate immune responses.

It is now well established that both inherited and acquired forms of hemolytic disease can promote pulmonary vascular disease consequent of free hemoglobin (Hb) induced NO scavenging, elevations in reactive oxygen species and lipid peroxidation. It has recently been reported that oxidative stress can activate NFkB through a toll-like receptor 9 (TLR9) mediated pathway; further, TLR9 can be activated by either nuclear or mitochondrial DNA liberated by stress induced cellular trauma. We hypothesis that Hb induced lipid peroxidation and subsequent endothelial cell trauma is linked to TLR9 activation, resulting in IL-6 mediated pulmonary smooth muscle cell proliferation. We examined the effects of Hb on rat pulmonary artery endothelial and smooth muscle cells (rPAEC and rPASMC, respectively), and then utilized TLR9 and IL6 inhibitors, as well as the Hb and heme binding proteins (haptoglobin (Hp) and hemopexin (Hpx), respectively) to further elucidate the aforementioned mediators. Further, we explored the effects of Hb in vivo utilizing endothelial cell (EC) specific myeloid differentiation primary response gene-88 (MyD88) and TLR9 null mice. Our data show that oxidized Hb induces lipid peroxidation, cellular toxicity (5.5 ± 1.7 fold; p≤0.04), increased TLR9 activation (60%; p = 0.01), and up regulated IL6 expression (1.75±0.3 fold; p = 0.04) in rPAEC. Rat PASMC exhibited a more proliferative state (13 ± 1%; p = 0.01) when co-cultured with Hb activated rPAEC. These effects were attenuated with the sequestration of Hb or heme by Hp and Hpx as well as with TLR9 an IL-6 inhibition. Moreover, in both EC-MyD88 and TLR9 null mice Hb-infusion resulted in less lung IL-6 expression compared to WT cohorts. These results demonstrate that Hb-induced lipid peroxidation can initiate a modest TLR9 mediated inflammatory response, subsequently generating an activated SMC phenotype., Competing Interests: All authors have declared that no competing interests exists.

Haptoglobin (Hp) is an approved treatment in Japan for trauma, burns, and massive transfusion-related hemolysis. Additional case reports suggest uses in other acute hemolytic events that lead to acute kidney injury. However, Hp's protective effects on the pulmonary vasculature have not been evaluated within the context of mitigating the consequences of chronic hemoglobin (Hb) exposure in the progression of pulmonary hypertension (PH) secondary to hemolytic diseases. This study was performed to assess the utility of chronic Hp therapy in a preclinical model of Hb and hypoxia-mediated PH. Rats were simultaneously exposed to chronic Hb infusion (35 mg per day) and hypobaric hypoxia for 5 weeks in the presence or absence of Hp treatment (90 mg/kg twice a week). Hp inhibited the Hb plus hypoxia-mediated nonheme iron accumulation in lung and heart tissue, pulmonary vascular inflammation and resistance, and right-ventricular hypertrophy, which suggests a positive impact on impeding the progression of PH. In addition, Hp therapy was associated with a reduction in critical mediators of PH, including lung adventitial macrophage population and endothelial ICAM-1 expression. By preventing Hb-mediated pathology, Hp infusions: (1) demonstrate a critical role for Hb in vascular remodeling associated with hypoxia and (2) suggest a novel therapy for chronic hemolysis-associated PH., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Viral Haemorrhagic Fevers (VHF) such as Ebola Virus Disease (EVD) are of increasing concern to clinicians and public heath bodies across Europe and America due to the on-going epidemic in West Africa. We conducted an online study to assess clinicians' knowledge of VHF across six hospital sites in London. This showed suboptimal knowledge of Public Health England guidance, EVD epidemiology and the risk factors for acquiring VHF. Knowledge about VHF was dependent on seniority of grade with the most junior grade of doctors performing worse in several areas of the survey. Poor knowledge raises concerns that those at risk of VHF will be inappropriately risk stratified and managed. Education of doctors and other healthcare professionals about VHF is necessary to address these knowledge gaps.

Background: High altitude illnesses (HAI) are a risk factor for any individual who is exposed to a significant increase in altitude. To learn more about the epidemiology of HAI, we sought to determine if health records from a commercial trekking company could provide novel data on the prevalence of HAI, as well as efficacy data regarding common HAI therapeutics., Methods: Health parameters from 917 tourists ascending Mt. Kilimanjaro over a 10-yr period were analyzed for meaningful data., Results: Of all subjects, 70% experienced at least one instance of a symptom related to HAI (headache, nausea, vomiting, diarrhea, or loss of appetite) during the trek. Acetazolamide was used at least once by 90% of subjects and, of those who used acetazolamide, 92% began taking it on day 1 of the ascent. Acetazolamide was found to improve oxygen saturation 1.2% above 9842.5 ft (3000 m). Dexamethasone use 12 h prior to ascending above 18,996 ft (5790 m) decreased the probability of a subject exhibiting at least one AMS symptom at that altitude., Discussion: The prevalence of AMS symptoms was not reduced by taking 2 extra days to reach the summit of Mt. Kilimanjaro. Prophylactic acetazolamide modestly improved oxygen saturation; however, it did not reduce symptoms. Therapeutic dexamethasone, especially at higher altitudes, was effective at reducing symptoms. We conclude that meaningful high altitude physiological data can be obtained from private trekking companies.

Background: Chloride intracellular channel 4 (CLIC4) is highly expressed in the endothelium of remodeled pulmonary vessels and plexiform lesions of patients with pulmonary arterial hypertension. CLIC4 regulates vasculogenesis through endothelial tube formation. Aberrant CLIC4 expression may contribute to the vascular pathology of pulmonary arterial hypertension., Methods and Results: CLIC4 protein expression was increased in plasma and blood-derived endothelial cells from patients with idiopathic pulmonary arterial hypertension and in the pulmonary vascular endothelium of 3 rat models of pulmonary hypertension. CLIC4 gene deletion markedly attenuated the development of chronic hypoxia-induced pulmonary hypertension in mice. Adenoviral overexpression of CLIC4 in cultured human pulmonary artery endothelial cells compromised pulmonary endothelial barrier function and enhanced their survival and angiogenic capacity, whereas CLIC4 shRNA had an inhibitory effect. Similarly, inhibition of CLIC4 expression in blood-derived endothelial cells from patients with idiopathic pulmonary arterial hypertension attenuated the abnormal angiogenic behavior that characterizes these cells. The mechanism of CLIC4 effects involves p65-mediated activation of nuclear factor-κB, followed by stabilization of hypoxia-inducible factor-1α and increased downstream production of vascular endothelial growth factor and endothelin-1., Conclusion: Increased CLIC4 expression is an early manifestation and mediator of endothelial dysfunction in pulmonary hypertension.

The release of hemoglobin (Hb) with hemolysis causes vascular dysfunction. New evidence implicates Hb-induced NF-κB and hypoxia inducible factor (HIF) activation, which may be under the control of a Toll-like receptor (TLR)-signaling pathway. Nearly all TLR-signaling pathways activate the myeloid differentiation primary response gene-88 (MyD88) that regulates NF-κB. We hypothesized that the differing transition states of Hb influence endothelial cell permeability via NF-κB activation and HIF regulation through a MyD88-dependent pathway. In cultured human dermal microvascular endothelial cells (HMECs-1), we examined the effects of Hb in the ferrous (HbFe(2+)), ferric (HbFe(3+)), and ferryl (HbFe(4+)) transition states on NF-κB and HIF activity, HIF-1α and HIF-2α mRNA up-regulation, and monolayer permeability, in the presence or absence of TLR4, MyD88, NF-κB, or HIF inhibition, as well as superoxide dismutase (SOD) and catalase. Our data showed that cell-free Hb, in each transition state, induced NF-κB and HIF activity, up-regulated HIF-1α and HIF-2α mRNA, and increased HMEC-1 permeability. The blockade of either MyD88 or NF-κB, but not TLR4, attenuated Hb-induced HIF activity, the up-regulation HIF-1 and HIF-2α mRNA, and HMEC-1 permeability. The inhibition of HIF activity exerted less of an effect on Hb-induced monolayer permeability. Moreover, SOD and catalase attenuated NF-κB, HIF activity, and monolayer permeability. Our results demonstrate that Hb-induced NF-κB and HIF are regulated by two mechanisms, either MyD88 activation or Hb transition state-induced ROS formation, that influence HMEC-1 permeability.

Reactive oxygen species (ROS) formed during acute high altitude exposure contribute to cerebral vascular leak and development of acute mountain sickness (AMS). Nuclear factor (erythroid-derived 2)-related factor 2 (Nrf2) is a transcription factor that regulates expression of greater than 90% of antioxidant genes, but prophylactic treatment with Nrf2 activators has not yet been tested as an AMS therapy. We hypothesized that prophylactic activation of the antioxidant genome with Nrf2 activators would attenuate high-altitude-induced ROS formation and cerebral vascular leak and that some drugs currently used to treat AMS symptoms have an additional trait of Nrf2 activation. Drugs commonly used to treat AMS were screened with a luciferase reporter cell system for their effectiveness to activate Nrf2, as well as being tested for their ability to decrease high altitude cerebral vascular leak in vivo. Compounds that showed favorable results for Nrf2 activation from our screen and attenuated high altitude cerebral vascular leak in vivo were further tested in brain microvascular endothelial cells (BMECs) to determine if they attenuated hypoxia-induced ROS production and monolayer permeability. Of nine drugs tested, with the exception of dexamethasone, only drugs that showed the ability to activate Nrf2 (Protandim, methazolamide, nifedipine, amlodipine, ambrisentan, and sitaxentan) decreased high-altitude-induced cerebral vascular leak in vivo. In vitro, Nrf2 activation in BMECs before 24h hypoxia exposure attenuated hypoxic-induced hydrogen peroxide production and permeability. Prophylactic Nrf2 activation is effective at reducing brain vascular leak from acute high altitude exposures. Compared to acetazolamide, methazolamide may offer better protection against AMS. Nifedipine, in addition to its known vasodilatory activities in the lung and protection against high altitude pulmonary edema, may provide protection against brain vascular leak as well., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Cell-free hemoglobin (Hb) exposure may be a pathogenic mediator in the development of pulmonary arterial hypertension (PAH), and when combined with chronic hypoxia the potential for exacerbation of PAH and vascular remodeling is likely more pronounced. We hypothesized that Hb may contribute to hypoxia-driven PAH collectively as a prooxidant, inflammatory, and nitric oxide (NO) scavenger. Using programmable micropump technology, we exposed male Sprague-Dawley rats housed under room air or hypoxia to 12 or 30 mg per day Hb for 3, 5, and 7 wk. Blood pressure, cardiac output, right ventricular hypertrophy, and indexes of pulmonary vascular remodeling were evaluated. Additionally, markers of oxidative stress, NO bioavailability and inflammation were determined. Hb increased pulmonary arterial (PA) pressure, pulmonary vessel wall stiffening, and right heart hypertrophy with temporal and dose dependence in both room air and hypoxic cohorts. Hb induced a modest increase in plasma oxidative stress markers (malondialdehyde and 4-hydroxynonenal), no change in NO bioavailability, and increased lung ICAM protein expression. Treatment with the antioxidant Tempol attenuated Hb-induced pulmonary arterial wall thickening, but not PA pressures or ICAM expression. Chronic exposure to low plasma Hb concentrations (range = 3-10 μM) lasting up to 7 wk in rodents induces pulmonary vascular disease via inflammation and to a lesser extent by Hb-mediated oxidation. Tempol demonstrated a modest effect on the attenuation of Hb-induced pulmonary vascular disease. NO bioavailability was found to be of minimal importance in this model.

Introduction: Patients are increasingly taking herbal supplements for a variety of reasons. This has brought into question doctors knowledge about herbal medicines., Method: A cross-sectional web-based survey of 84 doctors working within the Department of Medicine at a District General Hospital was carried out looking at doctor's knowledge about herbal medicines., Results: 53 doctors took part. Of these, the majority were trainees in Medicine (42) 79%. Only (15) 28% routinely ask patients about herbal medicine use when taking a drug history. Doctor's knowledge about herbal Medicines was poor., Conclusion: We need to re-examine our current teaching programmes to ensure that education about common herbal medicines and important sources of information are provided to doctors to improve patient safety.

This qualitative study describes how forty-one perimenopausal and postmenopausal women with coronary heart disease (CHD) perceive their illness experience. Five focus groups were conducted by a professional facilitator at two community hospitals in New Jersey. All data were collected and analyzed based on the grounded theory approach. Findings indicate that participants often failed to recognize the significance of risk factors and symptoms, and even denied the presence of disease following diagnosis and treatment. Consequences of illness centered on women's efforts to maintain control over their health and their lives. Findings also indicate that there is a gap between the desire for knowledge and the ability to access and assimilate information in key areas regarding CHD and personal health behaviors. The insights provided by these women have several implications for future research and contribute valuable information related to the needs of this population.