1 Clinica Pediatrica 2 a , Dipartimento di Scienze Biomediche e Biotecnologie, Università di Cagliari Ospedale Regionale Microcitemie, ASL 8 Cagliari, Cagliari
2 Istituto di Neurogenetica e ...Neurofarmacologia del Consiglio Nazionale delle Ricerche, Monserrato, Cagliari, Italy
Correspondence: Renzo Galanello, Ospedale Regionale Microcitemie, Via Jenner s/n 09121 Cagliari, Italy. E-mail: renzo.galanello{at}mcweb.unica.it
Ten patients with thalassemia intermedia with variable severity and apparent simple heterozygosis for β 0 39 C>T nonsense mutation were submitted to clinical, hematologic and molecular studies. The presence of an unknown molecular defect (silent β-thalassemia) unlinked to the β cluster interacting with the heterozygous β thalassemia, was previously postulated in these families. Analysis of the globin gene cluster with PCR-based methods (MLPA, GAP-PCR, digestion with restriction enzymes) detected complex rearrangements in the cluster. A duplication of the globin gene locus, including the upstream regulatory region, was present in all the patients, associated in some of them with deletion or non-deletion thalassemia. The variability of the clinical phenotype correlates with the degree of the globin chain imbalance. The presence of globin cluster duplication should be considered in patients heterozygote for β-thalassemia with thalassemia intermedia phenotype and in the carriers of suspected silent β thalassemia.
Key words: thalassemia intermedia, -globin gene quadruplication, silent β thalassemia, MLPA.
Projects attempting the direct detection of WIMP dark matter share the common problem of eliminating sources of background or using techniques to distinguish background events from true signals. ...Although experiments such as DarkSide have achieved essentially background free exposures through careful choice of materials and application of efficient veto techniques, there will still be a high burden of proof to convince the greater scientific community when a discovery is claimed. A directional signature in the data would provide extremely strong evidence to distinguish a true WIMP signal from that of an isotropic background. Two-phase argon time projection chambers (TPCs) provide an experimental apparatus which can both be scaled to the ton-scale size required to accommodate the low cross-section expected for WIMP interactions and have an anisotropy that could be exploited to evaluate the polar angles of the resulting nuclear recoils from WIMP collisions with target nuclei. Our studies show that even a modest resolution in the polar angle reconstruction would offer a powerful tool to detect a directional signature. In this contribution, the status of the ReD experiment, which is under construction at Naples University, will be also shown. The aim of the project is to assess and enhance the directionality of two-phase argon TPCs. ReD will use a small TPC exposed to a beam of mono-energetic neutrons to study the so called “columnar recombination” in liquid argon. This development could have high impact on the future experiments in the field, opening up the potential to find conclusive evidence for dark matter or disprove the WIMP hypothesis at and above the mass range explored by planned accelerator experiments.
The graph coloring problem is an optimization problem involving the
assignment of one of q colors to each vertex of a graph such that no two
adjacent vertices share the same color. This problem is ...NP-hard and arises in
various practical applications. In this work, we present a novel algorithm that
leverages graph neural networks to tackle the problem efficiently, particularly
for large graphs. We propose a physics-inspired approach that leverages tools
used in statistical mechanics to improve the training and performance of the
algorithm. The scaling of our method is evaluated for different connectivities
and graph sizes. Finally, we demonstrate the effectiveness of our method on a
dataset of Erdos-Renyi graphs, showing its applicability also in hard-to-solve
connectivity regions where traditional methods struggle.
We investigate the possibility to apply quantum machine learning techniques for data analysis, with particular regard to an interesting use-case in high-energy physics. We propose an anomaly ...detection algorithm based on a parametrized quantum circuit. This algorithm has been trained on a classical computer and tested with simulations as well as on real quantum hardware. Tests on NISQ devices have been performed with IBM quantum computers. For the execution on quantum hardware specific hardware driven adaptations have been devised and implemented. The quantum anomaly detection algorithm is able to detect simple anomalies like different characters in handwritten digits as well as more complex structures like anomalous patterns in the particle detectors produced by the decay products of long-lived particles produced at a collider experiment. For the high-energy physics application, performance is estimated in simulation only, as the quantum circuit is not simple enough to be executed on the available quantum hardware. This work demonstrates that it is possible to perform anomaly detection with quantum algorithms, however, as amplitude encoding of classical data is required for the task, due to the noise level in the available quantum hardware, current implementation cannot outperform classic anomaly detection algorithms based on deep neural networks.
From the Dipartimento di Scienze Biomediche e Biotecnologie, Università di Cagliari, Ospedale Microcitemico ASL8- Cagliari, Italy (RO, RG, NG, LM, GF) David Geffen School of Medicine, University of ...California, Los Angeles, USA (TG, EN)
Correspondence: Elizabeta Nemeth, UCLA, Department of Medicine, 10833 LeConte Ave, CHS 37-131 Los Angeles, CA 90095, USA. E-mail: enemeth{at}mednet.ucla.edu
Background and Objectives: Patients with ß-thalassemia, like those with genetic hemochromatosis, develop iron overload due to increased iron absorption, and their iron burden is further exacerbated by transfusion therapy. Hepcidin, a hepatic hormone, regulates systemic iron homeostasis by inhibiting the absorption of iron from the diet and the recycling of iron by macrophages. In turn, hepcidin release is increased by iron loading and inhibited by erythropoietic activity. Hepcidin deficiency is the cause of iron overload in most forms of hereditary hemochromatosis. We sought to determine hepcidins role in the pathogenesis of iron overload in ß-thalassemia.
Design and Methods: We assessed the degree of iron overload in thalassemia intermedia and major patients by measuring hepatic iron concentration in liver biopsy samples and serum ferritin, estimated erythropoietic drive by assaying soluble transferrin receptor and serum erythropoietin levels and correlated these with urinary hepcidin measurements.
Results: Urinary hepcidin levels in ß-thalassemia demonstrate severe hepcidin deficiency in thalassemia intermedia. There was a strong inverse relationship between urinary hepcidin levels and both erythropoietin and soluble transferrin receptor, markers of erythropoietic activity. In contrast, hepcidin levels were elevated in thalassemia major, presumably due to transfusions that reduce erythropoietic drive and deliver a large iron load. Despite similar liver iron concentrations in the two conditions, serum ferritin was much lower in thalassemia intermedia.
Interpretation and Conclusions: In thalassemia intermedia, high erythropoietic drive causes severe hepcidin deficiency. The lack of hepcidin results in hyperabsorption of dietary iron, but also in iron depletion of macrophages, lowering their secretion of ferritin and, consequently, serum ferritin levels. In contrast, in thalassemia major, transfusions decrease erythropoietic drive and increase the iron load, resulting in relatively higher hepcidin levels. In the presence of higher hepcidin levels, dietary iron absorption is moderated and macrophages retain iron, contributing to higher serum ferritin. In the future, hepcidin measurements may allow a more accurate assessment of the degree of iron overload and the maldistribution of iron in thalassemia.
Key words: ineffective erythropoiesis, iron absorption, hepatic iron, iron-loading anemia.
We propose a quantum version of a generative diffusion model. In this algorithm, artificial neural networks are replaced with parameterized quantum circuits, in order to directly generate quantum ...states. We present both a full quantum and a latent quantum version of the algorithm; we also present a conditioned version of these models. The models' performances have been evaluated using quantitative metrics complemented by qualitative assessments. An implementation of a simplified version of the algorithm has been executed on real NISQ quantum hardware.
Heart-touching Chilaiditi's syndrome Sorrentino, Dario; Bazzocchi, Massimo; Badano, Luigi ...
World journal of gastroenterology : WJG,
08/2005, Letnik:
11, Številka:
29
Journal Article
Odprti dostop
Symptomatic hepato-diaphragmatic interposition of a bowel loop or Chilaiditi's syndrome is a peculiar anatomical condition most often found by chance. Its described symptoms range from intermittent, ...mild abdominal pain and dyspepsia to acute intestinal obstruction. We report a case of hepato-diaphragmatic migration of the hepatic flexure of the colon associated to an unusual, heretofore unreported, angina-like pain exclusively evoked by the left lateral decubitus. To maximize the chance of observing anatomical changes in different postures, computed tomography of the chest and abdomen was performed after air insufflation into the colon. While frank herniation into the chest was excluded, the scan showed that the hepatic flexure-with the interposition of the diaphragm-came in contact with the right side of the heart in the left lateral, but not in the supine, decubitus. This finding was reproduced by echocardiography which also showed virtually unaltered hemodynamics after the change of posture. ECG, left and right ventricular global and regional function as well as cardiac injury markers also remained unchanged during the maneuver, indicating that the pain evoked by the latter was unlikely due to myocardial ischemia. This case suggests that Chilaiditi's syndrome should be included among the possible, although rare, causes of unexplained angina-like symptoms.
:
Initial diagnosis of cavernous transformation of the portal vein (portal cavernoma) is rarely made in adults. Its main clinical manifestation is upper gastrointestinal hemorrhage due to variceal ...bleeding. More rarely, diagnosis is made from obstructive jaundice. In children, this condition is frequently associated to prehepatic portal hypertension and congenital anomalies, the most frequent of which are atrial septal defects or malformations of the biliary tract or of the inferior vena cava.
We describe here a case of a 23‐year‐old female presenting with massive hematemesis due to the presence of esophageal and small intestinal varices. She had a cavernous transformation of the portal vein with prehepatic portal hypertension associated with heretofore unreported malformations such as right pulmonary hypoplasia, cardiac dextroposition, and right renal ectopia. A unifying hypothesis (e.g. an intrauterine vascular insult) to explain the pathogenesis of these defects seems unlikely. Appropriate tests failed to identify specific functional abnormalities in these organs. Although she bled more than once, the combination of sclerotherapy and β‐blockers has been, thus far, able to control the major clinical consequences of this disease.
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