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Improved Biocompatibility of Amino-Functionalized Graphene Oxide in Caenorhabditis elegans
Get PDFGraphene oxide (GO) holds high promise for diagnostic and therapeutic applications in nanomedicine but reportedly displays immunotoxicity, underlining the need for developing functionalized GO with improved biocompatibility. This study describes adverse effects of GO and amino‐functionalized GO (GONH2) during Caenorhabditis elegans development and ageing upon acute or chronic exposure. Chronic GO treatment throughout the C. elegans development causes decreased fecundity and a reduction of animal size, while acute treatment does not lead to any measurable physiological decline. However, RNA‐Sequencing data reveal that acute GO exposure induces innate immune gene expression. The p38 MAP kinase, PMK‐1, which is a well‐established master regulator of innate immunity, protects C. elegans from chronic GO toxicity, as pmk‐1 mutants show reduced tissue‐functionality and facultative vivipary. In a direct comparison, GONH2 exposure does not cause detrimental effects in the wild type or in pmk‐1 mutants, and the innate immune response is considerably less pronounced. This work establishes enhanced biocompatibility of amino‐functionalized GO in a whole‐organism, emphasizing its potential as a biomedical nanomaterial
Dumping Syndrome: A Rare Complication Following Nissen Fundoplication
Get PDFDumping syndrome (DS) is a debilitating entity with gastrointestinal and vasomotor symptoms due to rapid gastric emptying. It is a rare complication of Nissen fundoplication in adults.
We report the case of a patient with oesophageal compressive symptoms (dysphagia, oesophageal food impaction and regurgitation) and frequent episodes of sweating and hypoglycaemia after a Nissen fundoplication to treat gastroesophageal reflux disease. Investigation revealed severe oesophagogastric stenosis and excluded insulinoma and other causes of hypoglycaemia. An oral glucose tolerance test and gastric emptying scintigraphy were performed, supporting the diagnosis of DS
Severe FMF Presentation with Rare Association of MEFV Variants (p.Pro369Ser/p.Glu148Gln)
Get PDFWe report the case of a 28-year-old man who presented with recurring episodes of high fever, pleural and pericardial effusions and bilateral hydrocele. He was diagnosed with familial Mediterranean fever (FMF) and responded well to colchicine therapy. Genetic testing showed variants of the MEFV gene (p.Pro369Ser and p.Glu148Gln) previously independently described as having a more benign course of the disease. Their association is very rarely reported. Our patient and our review of the literature suggest that these genetic variants are associated with indolent courses but might also trigger the classic symptoms seen in severe FMF, probably in a compound heterozygous fashion. The combination of these variants should be taken into consideration in the diagnosis and management of patients
Focal Neurological Deficit Secondary to Severe Hyponatraemia Mimicking Stroke
Get PDFHyponatraemia is a common electrolyte abnormality seen by internists. Clinical features of hyponatraemia are primarily related to CNS dysfunction, and depend on the severity and acuity of changes in serum sodium concentration. Neurological manifestations of hyponatraemia range from nausea and malaise, with a mild reduction in the serum sodium, to lethargy, decreased level of consciousness, headache, seizures and coma in extreme cases. Focal neurological deficits are very rare in the setting of hyponatraemia. Here, we describe a patient with acute severe symptomatic hyponatraemia presenting with focal neurological deficits that resolved after correction of acute hyponatraemia
Spindle Coma in the Intensive Care Unit: Different Aetiologies – Different Outcomes
Get PDFSpindle coma is an electroclinical entity that has been used to describe an EEG pattern of “sleep-like” activity in comatose patients. Although it has been associated with favourable prognosis, its aetiology is one of the key factors for patient outcome. The authors present three cases of spindle coma with different aetiologies (amitriptyline overdose, pontine myelinolysis and hypoxic-ischaemic encephalopathy) that culminated in different outcomes
Magnetic Resonance Direct Thrombus Imaging (MRDTI) Can Distinguish Between Old and New Thrombosis in the Abdominal Aorta: a Case Report
Get PDFA 43-year-old man complaining of abdominal angina for several months showed a large suprarenal aneurysm of the abdominal aorta with extensive circumferential wall thrombosis, complete occlusion of the right renal artery and a critically stenosed left renal artery on CT angiography. He suffered from severe hypertension and renal failure. A percutaneous transluminal angioplasty (PTA) was planned. After the PTA procedure, which was complicated by the development of left renal artery occlusion, successful rescue revascularization surgery was performed. Since we were hesitant to start anticoagulant treatment because of a high bleeding risk, magnetic resonance direct thrombus imaging was performed to assess the age of the extensive arterial thrombosis. The aortic thrombus showed a low signal intensity, which is indicative of chronic rather than acute thrombosis. Therefore, oral anticoagulant treatment was not started. The patient recovered without major complications
Heating in collisionless plasmas: Do collisions play an effective role?
Get PDFHigh temperature and low density plasmas are ubiquitous in the Universe. These systems often exhibit a turbulent dynamics, characterized by the cross-scale coupling of fluid and kinetic scales and by the inhomogeneous development of coherent spatial and temporal structures. At smaller scales the energy of fluctuations is dissipated and plasma is eventually heated. Despite collisions are usually ruled out from the description of these systems, it has been recently shown that plasma collisionality may be locally enhanced, owing to the presence of fine structures in velocity space. In this perspective, further insights are here given by comparing the characteristic times of collisional dissipation with the time scales of other collisionless processes, such as nonlinear coupling and linear instability onset. When taking into account fine velocity structures, these characteristic times could be comparable. A novel scenario for the description of heating in weakly-collisional plasmas, even including inter-particle collisions, is finally proposed
Assessment of the particle radiation environment at L1 and near-Earth space
Get PDFWe investigated the particle radiation environment at the Lagrangian point L1 and in the near-Earth space by performing a systematic analysis of the proton flux data recorded by the EPAM and CPME particle instruments, aboard ACE and IMP-8 in the energy range ∼0.05-5 MeV and 0.29-440 MeV, respectively. We computed the cumulative distribution functions for all the energy channels of each instrument and studied the radiation variation with respect to solar activity. We obtained energetic proton spectra at 90% cumulative probability for different time periods and determined the worst case scenario, which can be used for operational purposes of the ATHENA mission and for Space Weather related hazards
Nuclear physics for cultural heritage
Get PDFWe report about the expert review, published by the Nuclear Physics Division of the European Physical Society (NPD EPS), which aims to provide the public with a popular and accessible account of the latest developments in the field of nuclear physics application for cultural heritage. The contributions from a range of leading specialists explain how applied atomic and nuclear techniques can be used to obtain information that can help us to understand the way of life in ancient times and how they can be used to conserve cultural heritage treasures. This topical review draws heavily on European work and is extensively illustrated with important discoveries and examples from archaeology, pre-history, history, geography, culture, religion and curation. It outlines key advances in a wide range of cross-disciplinary techniques and has been written with the minimum of technical detail so as to be accessible by as wide as possible audience. The large number of groups and laboratories working in the study and preservation of cultural heritage using mainly nuclear physics methods across Europe indicates the enormous effort and importance paid by society to this activity
Design and test of an innovative static thin target for intense ion beams
Get PDFIn the present work an innovative design for thin target suited for high intensity beam is proposed, which consists in the deposition of the target material on a substrate of pyrolytic graphite, whose in-plane thermal conductivity
allows a quick dissipation into a heat sink. Such a target cooling system has been designed for the NUMEN experiment (hosted at LNS-INFN, Catania), which will use targets of particular isotopes under highly intense ion beams. The time evolution and the spatial distribution of the temperature have been numerically calculated. Results of these calculations show that the target/graphite system can tolerate ion beams with intensities of about 50 eμA and energy of 15 MeV/u. A significant nonuniformity in the target thickness would limit the energy resolution of the reaction products. A technique, based on the α-particle transmission, is used for measuring the thickness and uniformity of the target. Preliminary results from tests with this technique applied to the graphite substrate are shown