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Type C hepatic encephalopathy (HE) is a complex neuropsychiatric disorder occurring as a consequence of chronic liver disease. Alterations in energy metabolism have been suggested in type C HE, but $\textit{in vivo}$ studies on this matter remain sparse and have reported conflicting results. Here, we propose a novel preclinical $^{18}$F-FDG PET methodology to compute quantitative 3D maps of the regional cerebral metabolic rate of glucose (CMR$_{glc}$) from a labelling steady-state PET image of the brain and an image-derived input function. This quantitative approach shows its strength when comparing groups of animals with divergent physiology, such as HE animals. PET CMR$_{glc}$ maps were registered to an atlas and the mean CMR$_{glc}$ from the hippocampus and the cerebellum were associated to the corresponding localized $^{1}$H MR spectroscopy acquisitions. This study provides for the first time local and quantitative information on both brain glucose uptake and neurometabolic profile alterations in a rat model of type C HE. A 2-fold lower brain glucose uptake, concomitant with an increase in brain glutamine and a decrease in the main osmolytes was observed in the hippocampus and in the cerebellum. These novel findings are an important step towards new insights into energy metabolism in the pathophysiology of HE., 30 pages, 6 figures

The invasive behavior of glioblastoma, the most aggressive primary brain tumor, is considered highly relevant for tumor recurrence. However, the invasion zone is difficult to visualize by Magnetic Resonance Imaging (MRI) and is protected by the blood brain barrier, posing a particular challenge for treatment. We report biological features of invasive growth accompanying tumor progression and invasion based on associated metabolic and transcriptomic changes observed in patient derived orthotopic xenografts (PDOX) in the mouse and the corresponding patients’ tumors. The evolution of metabolic changes, followed in vivo longitudinally by 1H-Magnetic Resonance Spectroscopy (MRS) at ultra-high field, reflected growth and the invasive properties of the human glioblastoma transplanted into the brains of mice (PDOX). Comparison of MRS derived metabolite signatures, reflecting temporal changes of tumor development and invasion in PDOX, revealed high similarity to spatial metabolite signatures of combined multi-voxel MRS analyses sampled across different areas of the patients’ tumors. Pathway analyses of the transcriptome associated with the metabolite profiles of the PDOX, identified molecular signatures of invasion, comprising extracellular matrix degradation and reorganization, growth factor binding, and vascular remodeling. Specific analysis of expression signatures from the invaded mouse brain, revealed extent of invasion dependent induction of immune response, recapitulating respective signatures observed in glioblastoma. Integrating metabolic profiles and gene expression of highly invasive PDOX provided insights into progression and invasion associated mechanisms of extracellular matrix remodeling that is essential for cell-cell communication and regulation of cellular processes. Structural changes and biochemical properties of the extracellular matrix are of importance for the biological behavior of tumors and may be druggable. Ultra-high field MRS reveals to be suitable for in vivo monitoring of progression in the non-enhancing infiltration zone of glioblastoma.

Despite the improving imaging techniques, it remains challenging to produce magnetic resonance (MR) imaging fingerprints depicting severity of acute ischemia. The aim of this study was to evaluate the potential of the overall high-field 1 H MR Spectroscopy (1 H-MRS) neurochemical profile as a metabolic signature for acute ischemia severity in rodent brains. We modeled global ischemia with one-stage 4-vessel-occlusion (4VO) in rats. Vascular structures were assessed immediately by magnetic resonance angiography. The neurochemical responses in the bilateral cortex were measured 1 h after stroke onset by 1 H-MRS. Then we used Partial-Least-Squares discriminant analysis on the overall neurochemical profiles to seek metabolic signatures for ischemic severity subgroups. This approach was further tested on neurochemical profiles of mouse striatum 1 h after permanent middle cerebral artery occlusion, where vascular blood flow was monitored by laser Doppler. Magnetic resonance angiography identified successful 4VO from controls and incomplete global ischemia (e.g., 3VO). 1 H-MR spectra of rat cortex after 4VO showed a specific metabolic pattern, distinct from that of respective controls and rats with 3VO. Partial-Least-Squares discriminant analysis on the overall neurochemical profiles revealed metabolic signatures of acute ischemia that may be extended to mice after permanent middle cerebral artery occlusion. Fingerprinting severity of acute ischemia using neurochemical information may improve MR diagnosis in stroke patients.

Sertraline, a selective serotonin reuptake inhibitor, is commonly prescribed for the treatment of moderate-to-severe depression. We report a case of a 36-year-old male taking sertraline for 7 weeks prior to developing a dry cough, pleuritic chest pain, hypoxia and diffuse ground-glass attenuation with mediastinal lymphadenopathy on imaging. No infectious aetiology was identified and multiple causes of pneumonitis excluded. Sertraline-induced interstitial lung disease was subsequently diagnosed. Sertraline was discontinued and treatment commenced with a weaning course of oral dexamethasone, leading to a rapid reduction in oxygen requirement and successful discharge. Given the increasing prevalence of selective serotonin reuptake inhibitor use, it is vital that medical professionals can recognize sertraline as a rare, albeit potentially life-threatening, cause of interstitial lung disease—allowing for the rapid diagnosis and appropriate management of this condition.

Background The invasive behavior of glioblastoma is considered highly relevant for recurrence. However, the invasion zone is difficult to visualize, typically lies outside the resected and irradiated area, and is protected by the blood brain barrier, posing a particular challenge for treatment. We present biological features of invasive growth accompanying tumor progression and invasion based on associated metabolic and transcriptomic changes in patient derived orthotopic xenografts (PDOX) and corresponding patients. Methods Patients with suspected glioblastoma were enrolled (NCT02904525) and underwent 1H-MR spectroscopy and imaging (1H-MRS/I, 7T). Tissue obtained at surgery was transplanted orthotopically into immune-compromised mice. Longitudinal follow-up was performed by 1H-MRS/I (14.1T) on the injected and the contralateral side. The PDOX, the corresponding contralateral side, and the original human tumors underwent RNA-sequencing. Results The temporal changes of the metabolite profiles characterized the kinetics of invasive growth of PDOX, and were patient specific. Comparison of 1H-MRS derived metabolite signatures, reflecting temporal changes of tumor development and invasion in PDOX, revealed high similarity to spatial metabolite signatures of combined multi-voxel analyses of the patients’ tumors. Associations between the metabolite profiles and the combined transcriptome of the xenografts and the host, reflected molecular signatures of invasion, comprising extracellular matrix degradation and reorganization, growth factor binding, and vascular remodeling. Conclusion Integrating metabolic profiles and gene expression of highly invasive PDOX allows in vivo monitoring of progression in the non-enhancing tumor infiltration zone and provides insights into the remodeling of the extracellular matrix that is essential for cell-cell communication and regulation of cellular processes. The changes of the structural and biochemical properties of the extracellular matrix are of importance for the biological behavior of the tumors and may be subjected to therapeutic targeting.

Background Temporal artery biopsy (TAB) is considered the gold standard for diagnosing Giant Cell Arteritis (GCA). The aim of this study was to compare the functional utility of the 2016 revised ACR (rACR) criteria against the original ACR criteria with a view to avoiding TABs in select groups. We also aimed to investigate the temporal relationship of positive biopsies. Methods A retrospective study was conducted of patients undergoing TAB from August 2014 to August 2016, at a DGH. Data collected included patient demographics, history, biochemistry, time to TAB from commencement of steroids and histology. The ACR and the rACR scores and the relative TAB results were analysed using ROC to determine statistical measures of performance. Different score thresholds were applied to propose a clinical tool to be used as an adjunct in the management of suspected GCA. Results and Discussion Forty two TABs were performed during this period of which 10 were males and 32 females. ROC analysis showed significant relationships between both ACR and rACR to TAB result. The AUC for rACR was 0.880 (p Conclusion This study demonstrates the potential value of the rACR criteria and a simple clinical tool is proposed to stratify relevant patients with a view to avoiding unnecessary TAB. Prolonged wait between referral to TAB is also likely to reduce its validity.

Cerebral metabolism, which can be monitored by magnetic resonance spectroscopy (MRS), changes rapidly after brain ischaemic injury. Hyperpolarisation techniques boost 13C MRS sensitivity by several orders of magnitude, thereby enabling in vivo monitoring of biochemical transformations of hyperpolarised (HP) 13C-labelled precursors with a time resolution of seconds. The exogenous administration of the metabolite L-lactate was shown to decrease lesion size and ameliorate neurological outcome in preclinical studies in rodent stroke models, as well as influencing brain metabolism in clinical pilot studies of acute brain injury patients. The aim of this study was to demonstrate the feasibility of measuring HP [1-13C] L-lactate metabolism in real-time in the mouse brain after ischaemic stroke when administered after reperfusion at a therapeutic dose. We showed a rapid, time-after-reperfusion-dependent conversion of [1-13C] L-lactate to [1-13C] pyruvate and [13C] bicarbonate that brings new insights into the neuroprotection mechanism of L-lactate. Moreover, this study paves the way for the use of HP [1-13C] L-lactate as a sensitive molecular-imaging biosensor in ischaemic stroke patients after endovascular clot removal.

Percutaneous endoscopic gastrostomy was first described in 1980 (Gauderer et al, 1980), superseding surgical gastrostomy as a means of providing long-term enteral nutrition. Despite the commonality of this procedure, its associated morbidity and mortality rates are significant, with directly attributable rates of 1:30 and 1:150 respectively. Poor patient selection and poor management are the principal factors contributing to adverse outcomes. The 2004 National Confidential Enquiry into Patient Outcome and Death recorded that 19% of percutaneous endoscopic gastrostomy procedures performed were ‘futile or not indicated at all’. This article provides a practical approach to avoiding and treating complications associated with percutaneous endoscopic gastrostomy feeding.

AIMS: In the adult heart, Notch signalling regulates the response to injury. Notch inhibition leads to increased cardiomyocyte apoptosis, and exacerbates the development of cardiac hypertrophy and fibrosis. The role of Notch in the mesenchymal stromal cell fraction, which contains cardiac fibroblasts and cardiac precursor cells, is, however, largely unknown. In the present study, we evaluate, therefore, whether forced activation of the Notch pathway in mesenchymal stromal cells regulates pathological cardiac remodelling. METHODS AND RESULTS: We generated transgenic mice overexpressing the Notch ligand Jagged1 on the surface of cardiomyocytes to activate Notch signalling in adjacent myocyte and non-myocyte cells. In neonatal transgenic mice, activated Notch sustained cardiac precursor and myocyte proliferation after birth, and led to increased numbers of cardiac myocytes in adult mice. In the adult heart under pressure overload, Notch inhibited the development of cardiomyocyte hypertrophy and transforming growth factor-β/connective tissue growth factor-mediated cardiac fibrosis. Most importantly, Notch activation in the stressed adult heart reduced the proliferation of myofibroblasts and stimulated the expansion of stem cell antigen-1-positive cells, and in particular of Nkx2.5-positive cardiac precursor cells. CONCLUSIONS: We conclude that Notch is pivotal in the healing process of the injured heart. Specifically, Notch regulates key cellular mechanisms in the mesenchymal stromal cell population, and thereby controls the balance between fibrotic and regenerative repair in the adult heart. Altogether, these findings indicate that Notch represents a unique therapeutic target for inducing regeneration in the adult heart via mobilization of cardiac precursor cells.

The Prevention of Liver Fibrosis and Cancer in Africa (PROLIFICA) study began in 2011 in The Gambia, Sénégal and Nigeria. The study aims to reduce the risk of hepatocellular carcinoma (HCC) in West Africa through the suppression of the Hepatitis B virus (HBV). The biological samples collected allow for the detection of novel liver cancer biomarkers in the hope of improving the diagnostic ability of early disease states. The PROLIFICA platform hopes to improve cancer diagnostics whilst simultaneously providing the training, skills and infrastructure necessary to develop the quality of liver cancer care in West Africa.

BACKGROUND: Glioblastoma (GBM) are notorious for their invasive behavior. Little is known about the biology of the tumor cells and the microenvironment at the invasive front that is highly relevant for recurrence. These cells are technically difficult to visualize, lie usually outside the resected and irradiated area, and are behind the blood brain barrier that renders them difficult to treat. We present patient specific metabolic and transcriptomic features of invasive growth using corresponding patient derived xenografts (PDX). METHODS: Patients with suspected GBM were enrolled and underwent (1)H magnetic resonance spectroscopy and imaging ((1)H-MRS/I) at 7 Tesla. Tissue obtained at the subsequent resection was dissociated and transplanted orthotopically into mice (n=4 to 6). Mice were followed longitudinally by (1)H-MRS/I (14T). The PDX, the corresponding tissue of the contralateral side, and the original tumors were subjected to RNA sequencing. Tumor versus host (mouse) derived sequencing reads are computationally separated. RESULTS: Diffuse xenografts developed for 8 (IDHwt) of 9 patients within 2–5 months. (1)H-MRS at ultrahigh fields allowed reliable quantification of 22 metabolites. The temporal changes of the metabolite signatures characterized the kinetics of invasive growth on both, the injected and the contralateral side. At end stage the signatures corresponded well with histological findings. Migration to the contralateral side ranged in a patient dependent manner between < 1 to > 50% 50% of tumor cells. Comparison of MRS derived metabolite signatures at end stage and the corresponding human signatures compared best with voxels measured outside the core of the human tumor. Associations between the metabolite signatures and the transcriptome in the xenografts and the host will be discussed. CONCLUSION: Integration of metabolic profiles and gene expression of the tumor and the invaded brain may provide insights and tools for in vivo monitoring of treatment response in the infiltration zone. GRANTS: Swiss Bridge Award, Swiss Cancer Ligue

Recent evidence suggests that the heart possesses a greater regeneration capacity than previously thought. In the present study, we isolated undifferentiated precursors from the cardiac nonmyocyte cell population of neonatal hearts, expanded them in culture, and induced them to differentiate into functional cardiomyocytes. These cardiac precursors appear to express stem cell antigen–1 and demonstrate characteristics of multipotent precursors of mesodermal origin. Following infusion into normal recipients, these cells home to the heart and participate in physiological and pathophysiological cardiac remodeling. Cardiogenic differentiation in vitro and in vivo depends on FGF-2. Interestingly, this factor does not control the number of precursors but regulates the differentiation process. These findings suggest that, besides its angiogenic actions, FGF-2 could be used in vivo to facilitate the mobilization and differentiation of resident cardiac precursors in the treatment of cardiac diseases.

Temporal artery biopsy is the gold standard for Giant Cell Arteritis. However, timing of biopsy in crucial. Delay leads to false negative results.

The ability of Mn(2+) to follow Ca(2+) pathways upon stimulation transform them into remarkable surrogate markers of neuronal activity using activity-induced manganese-dependent MRI (AIM-MRI). In the present study, a precise follow-up of physiological parameters during MnCl2 and mannitol infusions improved the reproducibility of AIM-MRI allowing in-depth evaluation of the technique. Pixel-by-pixel T1 data were investigated using histogram distributions in the barrel cortex (BC) and the thalamus before and after Mn(2+) infusion, after blood brain barrier opening and after BC activation. Mean BC T1 values dropped significantly upon trigeminal nerve (TGN) stimulation (-38 %, P = 0.02) in accordance with previous literature findings. T1 histogram distributions showed that 34 % of T1s in the range 600-1500 ms after Mn(2+ )+ mannitol infusions shifted to 50-350 ms after TGN stimulation corresponding to a twofold increase of the percentage of pixels with the lowest T1s in BC. Moreover, T1 changes in response to stimulation increased significantly from superficial cortical layers (I-III) to deeper layers (V-VI). Cortical cytoarchitecture detection during a functional paradigm was performed extending the potential of AIM-MRI. Quantitative AIM-MRI could thus offer a means to interpret local neural activity across cortical layers while identification of the role of calcium dynamics in vivo during brain activation could play a key role in resolving neurovascular coupling mechanisms.

Low energy x-ray fluorescence (LEXRF) detection was optimized for imaging cerebral glucose metabolism by mapping the fluorine LEXRF signal of 19 F in 19 FDG, trapped as intracellular 19 F-deoxyglucose-6-phosphate ( 19 FDG-6P) at 1μm spatial resolution from 3μm thick brain slices. 19 FDG metabolism was evaluated in brain structures closely resembling the general cerebral cytoarchitecture following formalin fixation of brain slices and their inclusion in an epon matrix. 2-dimensional distribution maps of 19 FDG-6P were placed in a cytoarchitectural and morphological context by simultaneous LEXRF mapping of N and O, and scanning transmission x-ray (STXM) imaging. A disproportionately high uptake and metabolism of glucose was found in neuropil relative to intracellular domains of the cell body of hypothalamic neurons, showing directly that neurons, like glial cells, also metabolize glucose. As 19 F-deoxyglucose-6P is structurally identical to 18 F-deoxyglucose-6P, LEXRF of subcellular 19 F provides a link to in vivo 18 FDG PET, forming a novel basis for understanding the physiological mechanisms underlying the 18 FDG PET image, and the contribution of neurons and glia to the PET signal.

Background . Notch signaling is essential during development and in homeostasis of several organ systems. Mutations in Notch genes cause cardiac malformations. However the role of this pathway in the adult heart has not been addressed. Methods . We investigated Notch signaling in models of cardiac hypertrophy and failure. Notch activation was analyzed by immunostaining and quantitative RT-PCR. Cardiac response to stress was investigated in mice lacking Notch1 in the heart and in transgenics overexpressing Jagged1 in the myocardium. Results . The wild-type heart responded to hemodynamic stress by an upregulation of the Notch ligand Jagged1 on cardiac myocytes and an activation of Notch1. Immunostaining showed that Notch1 activation occurred predominantly in cardiomyocytes. Nkx2.5- and GATA4-positive cardiac precursor cells also activated Notch. In cultured cardiomyocytes, Notch signaling interfered with terminal differentiation. In vitro, proliferating Nkx2.5-positive precursor cells displayed intense NIC staining. Under differentiation conditions, these cells downregulated the Notch pathway and produced cardiomyocytes. Pharmacological inhibition of the Notch pathway in vivo exacerbated cardiac hypertrophy and was detrimental to the adaptive response of the heart to stress. Similarly, mice with cardiac-specific deletion of Notch1 exhibited cardiac fibrosis, impaired cardiac function and decreased survival. To investigate the effects of chronic Notch activation in the heart, we generated transgenics with cardiac Jagged1 overexpression. A large proportion (40 –50%) of these mice demonstrated atrial enlargement, impairment of ventricular function, and die at 3 months of age. Conclusions . Notch signaling is crucial for maintaining cardiac integrity in the adult mammalian heart. Activation of the Notch pathway relies on stimulated Jagged1 expression. In cardiomyocytes, Notch regulates the extent of the hypertrophic response and probably contributes to cell survival. In cardiac precursors, Notch controls cardiogenic differentiation. Importantly, both chronic inhibition and activation are detrimental to cardiac function, suggesting that fine tuning of Notch signaling in the heart is mandatory for proper cardiac homeostasis.

In the western world, heart failure, which develops for instance secondary to myocardial infarction, is a major cause of death. Usually, the heart adapts to a primary insult through cardiomyocyte hypertrophy. The emerging concept, however, is that cardiac stem cells contribute to cardiomyocyte renewal in the myocardium. The rate of replacement is low in the normal heart, and is thought to be higher during the response to injury. In this context, the present work aims at generating a transgenic model of inducible cardiomyocyte death to evaluate the degree of cardiac stem cell mobilization during the adaptation of the heart to stress. Therefore, we produced transgenic mice with cardiac-specific overexpression of the human CD25 (hCD25) under control of the a-MHC promoter. This transmembrane protein is inactive in the mouse. However, LMB2, an immunotoxin derived from the Pseudomonas exotoxin directed against hCD25, can be administrated to specifically target hCD25-expressing cardiomyocytes and induce apoptosis. Cardiac-specific expression of hCD25 in transgenics was demonstrated by RT-PCR, Western blot analysis and immunohistochemistry. Administration of LMB2 to neonatal transgenic cardiomyocytes in culture resulted in significant cell death. Surviving cardiomyocytes showed abnormal, star-shaped morphology and disorganized sarcomeric structure. In vivo, administration of LMB2 to neonatal transgenics resulted in increased apoptosis after LMB2 injection and significant mortality. The number of dying mice increased proportionally to the dose of injected LMB2. Surviving transgenic mice sacrificed 3 days after LMB2 administration showed decreased cardiac weight, disorganized cardiac tissue and increased fibrosis. In adult transgenic mice, LMB2 treatment resulted in impaired cardiac function, as shown by echocardiography analysis, and animal death at doses of 300 ng/g and above. Post-mortem analysis revealed necrotic and fibrous cardiac tissues. This model is currently used to induce non-lethal apoptosis in adult animals in view to investigate cardiac precursor recruitment and potential regeneration in the damaged heart.

In the damaged heart, cardiac adaptation relies primarily on cardiomyocyte hypertrophy. The recent discovery of cardiac stem cells in the postnatal heart, however, suggests that these cells could participate in the response to stress via their capacity to regenerate cardiac tissues. Using models of cardiac hypertrophy and failure, we demonstrate that components of the Notch pathway are up-regulated in the hypertrophic heart. The Notch pathway is an evolutionarily conserved cell-to-cell communication system, which is crucial in many developmental processes. Notch also plays key roles in the regenerative capacity of self-renewing organs. In the heart, Notch1 signaling takes place in cardiomyocytes and in mesenchymal cardiac precursors and is activated secondary to stimulated Jagged1 expression on the surface of cardiomyocytes. Using mice lacking Notch1 expression specifically in the heart, we show that the Notch1 pathway controls pathophysiological cardiac remodeling. In the absence of Notch1, cardiac hypertrophy is exacerbated, fibrosis develops, function is altered, and the mortality rate increases. Therefore, in cardiomyocytes, Notch controls maturation, limits the extent of the hypertrophic response, and may thereby contribute to cell survival. In cardiac precursors, Notch prevents cardiogenic differentiation, favors proliferation, and may facilitate the expansion of a transient amplifying cell compartment.

Open Innovation and Services Science are two distinct paradigms that share some principles 0. While some attempts to investigate open innovation according to a service science perspective exist, there is currently a gap with regards to the analysis of intermediaries of open innovation according to a service science perspective and even more regarding to recent trends about smart service system. This paper aims to fill this gap and, to this purpose, we present two interesting and original results. After an analysis of the key features of Open Innovation Intermediaries, we discuss a characterization of these intermediaries as service systems by mapping their features on the ten fundamental concepts of a service system. Next we propose a new model that goes in the direction of the convergence between service and cognitive system (smart service system) and aims at overcoming some traditional issues of the intermediaries. The new model foresees the distribution of Open Innovation Intermediaries features, enhanced with a set of cognitive assistants to the stakeholders within open innovation processes, and proposes the adoption of responsible innovation frameworks as a base to add right and responsibilities to cognitive assistants.

The Notch signaling pathway is a communication system between adjacent cells, mediated by transmembrane receptors (Notch1-4) and ligands (Jagged1 and 2, Delta-like1, 3, and 4). Notch is essential for the development and homeostasis of several self-renewing organ systems. Notch is also essential in the developing heart, and mutations in Notch genes cause cardiac malformations and congenital heart disease. Recently, using loss-of-function studies, we showed that the Notch1 receptor controlled the response to injury in the adult heart by limiting myocyte hypertrophy, enhancing myocyte survival, promoting precursor proliferation, controlling cardiogenic differentiation, and reducing interstitial fibrosis. In addition, our data suggested that upregulation of Jagged1 expression constituted a primary response in the stressed myocardium, suggesting that this ligand mediated Notch signaling in the postnatal heart. Therefore, to analyze the effects of a chronic Jagged1-induced Notch activation on the cardiac response to stress, we generated transgenic mice overexpressing Jagged1 in cardiomyocytes using the α-myosin heavy chain gene promoter (TGMHCJ1 mice). These mice expressed 100-500 fold Jagged1 mRNA relative to wild-type (WT) controls. The overexpression of Jagged1 on the surface of cardiomyocytes was confirmed by Western blotting and immunofluorescence staining. Consequently, the percentage of cardiac cells with an activated Notch pathway was higher in TGMHCJ1 mice than in WT animals. The expression of the Notch target genes Hes1 and Hey2 was also activated. Echocardiographic analysis under basal conditions revealed an enlargement of the right ventricle (RV) with a diminished left ventricle (LV) mass and chamber size in adults. TGMHCJ1 mice displayed increased juvenile mortality. The severity of the phenotype was dependent on the level of Jagged1 expression. Immunofluorescence analysis revealed myocyte hypertrophy and disarray in the RV of TGMHCJ1 mice whereas, myocytes in the LV were not affected. Moreover, when subjected to transaortic constriction (TAC), TGMHCJ1 mice demonstrated an impaired LV hypertrophic response to pressure overload and reduced cardiac fibrosis. These results indicate that chronic activation of Notch affects differently left and right ventricle integrity under physiological and pathological conditions.