3,586 research outputs found
clinical presentation and prevalence of spontaneous bacterial peritonitis in patients with cryptogenic cirrhosis and features of metabolic syndrome
BACKGROUND:Nonalcoholic steatohepatitis (NASH) may progress to cirrhosis. The prevalence and clinical relevance that spontaneous bacterial peritonitis may have in complicating ascites due to NASH-related cirrhosis have yet to be defined.METHODS:Among 611 cases of cirrhosis-associated ascites, 45 patients with cryptogenic cirrhosis were retrospectively identified. Of these, 36 patients and a control group of subjects with viral-associated ascites were followed up and compared in a case control study. Information on the onset of ascites, with or without spontaneous bacterial peritonitis, history of risk factors for multimetabolic syndrome, and serological and ascitic laboratory data were compared between groups.RESULTS:Spontaneous bacterial peritonitis occurred significantly more often in patients with cryptogenic cirrhosis than in equally symptomatic viral controls. The prevalence of obesity, diabetes and spontaneous bacterial peritonitis was significantly higher in patients with cryptogenic cirrhosis. Although liver function was similar in both groups, cryptogenic cirrhosis patients had lower aminotransferase levels. Multivariate analysis identified diabetes, juvenile obesity and spontaneous bacterial peritonitis as independent factors associated with ascites due to cryptogenic cirrhosis.CONCLUSIONS:Features suggestive of NASH are more frequently observed in patients with ascites and cryptogenic cirrhosis than in age- and sex-matched ascitic patients with well-defined viral etiology. Ascites may be a presenting symptom of NASH-related cirrhosis, and affected patients have a twofold greater risk of spontaneous bacterial peritonitis
First assessment on suspension parameter optimization for a solar-powered vehicle
Optimization of suspension parameters with respect to comfort and road holding is a challenging issue for solar-powered cars, due to in-wheel electric engines on very light vehicles, carrying payloads which can exceed their total mass. The solar-powered car considered in this study was designed and manufactured for racing by the University of Bologna; with a mass of 300 kg and a payload of 320 kg due to four occupants, using 5 m2 of monocrystalline silicon photovoltaic panel on the roof, 64 kg of lithium-ion batteries and two electric engines coupled directly to the rear wheels, it can achieve either a range of 600 km at cruising speed, or velocity peaks of 120 km/h. In this contribution, equivalent vertical stiffness and equivalent damping coefficients are optimized for both axles, achieving results that in terms of comfort and road holding are comparable to those of standard passenger cars
Functional brain network topology across the menstrual cycle is estradiol dependent and correlates with individual well-being
The menstrual cycle (MC) is a sex hormone-related phenomenon that repeats itself cyclically during the woman's reproductive life. In this explorative study, we hypothesized that coordinated variations of multiple sex hormones may affect the large-scale organization of the brain functional network and that, in turn, such changes might have psychological correlates, even in the absence of overt clinical signs of anxiety and/or depression. To test our hypothesis, we investigated longitudinally, across the MC, the relationship between the sex hormones and both brain network and psychological changes. We enrolled 24 naturally cycling women and, at the early-follicular, peri-ovulatory, and mid-luteal phases of the MC, we performed: (a) sex hormone dosage, (b) magnetoencephalography recording to study the brain network topology, and (c) psychological questionnaires to quantify anxiety, depression, self-esteem, and well-being. We showed that during the peri-ovulatory phase, in the alpha band, the leaf fraction and the tree hierarchy of the brain network were reduced, while the betweenness centrality (BC) of the right posterior cingulate gyrus (rPCG) was increased. Furthermore, the increase in BC was predicted by estradiol levels. Moreover, during the luteal phase, the variation of estradiol correlated positively with the variations of both the topological change and environmental mastery dimension of the well-being test, which, in turn, was related to the increase in the BC of rPCG. Our results highlight the effects of sex hormones on the large-scale brain network organization as well as on their possible relationship with the psychological state across the MC. Moreover, the fact that physiological changes in the brain topology occur throughout the MC has widespread implications for neuroimaging studies
Sensitive gravity-gradiometry with atom interferometry: progress towards an improved determination of the gravitational constant
We here present a high sensitivity gravity-gradiometer based on atom
interferometry. In our apparatus, two clouds of laser-cooled rubidium atoms are
launched in fountain configuration and interrogated by a Raman interferometry
sequence to probe the gradient of gravity field. We recently implemented a
high-flux atomic source and a newly designed Raman lasers system in the
instrument set-up. We discuss the applications towards a precise determination
of the Newtonian gravitational constant G. The long-term stability of the
instrument and the signal-to-noise ratio demonstrated here open interesting
perspectives for pushing the measurement precision below the 100 ppm level
Effects of the combined action of a desensitizing gel and toothpaste on dentin hypersensitivity due to dental bleaching
Objectives: The present study is aimed at evaluating the effectiveness of a fluoride- and potassium nitrate-containing gel and toothpaste in reducing dentinal hypersensitivity due to dental bleaching. Materials and methods: Specific inclusion and exclusion criteria were used to recruit patients for the study. They were randomly allocated to a test or a placebo control group. Patients underwent a treatment of home dental bleaching with 10% carbamide peroxide. Dental shades were evaluated in a standardized environment and dentinal hypersensitivity was valuated by means of evaporation stimuli. A nominal scale was used to score the painful reaction. The patients were recalled 8, 15 and 28 days after the baseline for both shade and sensitivity assessment. Statistical analysis was performed using the Student’s T-test. Results: The patients recall rate was 96.9%. The statistical analysis demonstrated a significant reduction of the painful symptoms in the experimental group (p=0.031) while no statistically significant differences were evidenced in the control group at any follow-up recall (p>0.05).
Discussion: The tested agents proved to be safe and effective in the short term. Neither pigmentations nor interferences with the bleaching action of peroxides due to the desensitizing agents were observed. The compliance of the patients to the proposed protocol as well as the motivation to maintain good oral hygiene were paramount in the achievement of the reported results. Conclusions: The use of a desensitizing gel and toothpaste containing fluoride and potassium nitrate was effective in reducing dentinal hypersensitivity due to dental bleaching and did not interfere with the bleaching action of peroxides.
Clinical significance: Desensitizing gels and toothpastes containing fluoride and potassium nitrate can be considered safe and effective in the control of tooth sensitivity after dental bleaching
Network synchronization of groups
In this paper we study synchronized motions in complex networks in which
there are distinct groups of nodes where the dynamical systems on each node
within a group are the same but are different for nodes in different groups.
Both continuous time and discrete time systems are considered. We initially
focus on the case where two groups are present and the network has bipartite
topology (i.e., links exist between nodes in different groups but not between
nodes in the same group). We also show that group synchronous motions are
compatible with more general network topologies, where there are also
connections within the groups
Mutations in the SPAST gene causing hereditary spastic paraplegia arerelated to global topological alterations in brain functional networks
Aim: Our aim was to describe the rearrangements of the brain activity related to genetic mutations in the SPAST gene. Methods: Ten SPG4 patients and ten controls underwent a 5Â min resting state magnetoencephalography recording and neurological examination. A beamformer algorithm reconstructed the activity of 90 brain areas. The phase lag index was used to estimate synchrony between brain areas. The minimum spanning tree was used to estimate topological metrics such as the leaf fraction (a measure of network integration) and the degree divergence (a measure of the resilience of the network against pathological events). The betweenness centrality (a measure to estimate the centrality of the brain areas) was used to estimate the centrality of each brain area. Results: Our results showed topological rearrangements in the beta band. Specifically, the degree divergence was lower in patients as compared to controls and this parameter related to clinical disability. No differences appeared in leaf fraction nor in betweenness centrality. Conclusion: Mutations in the SPAST gene are related to a reorganization of the brain topology
Characterization of Colletotrichum strains associated with olive anthracnose in Sicily
Anthracnose caused by Colletotrichum spp. is the most damaging olive fruit disease in many countries, including Italy. This disease has been sporadically detected in Sicily, but new agronomic practices can increase risk of olive anthracnose in this region. An etiological study of the disease focused on local olive cultivars growing at the International Olive Germplasm Collection (IOGC) in Villa Zagaria, Enna, Sicily has been undertaken. During 2018 and 2019, 137 Colletotrichum strains were isolated from olives. Colony morphology, conidium characteristics, and multilocus sequence analyses aided identification of three species: C. acutatum (affecting 70% of symptomatic olives), C. gloeosporioides, and C. cigarro. Three C. acutatum strains (B1316, P77, and P185), and one stram of each C. gloeosporioides (C2.1) and C. cigarro (Perg6B) were evaluated for pathogenicity on olive fruits from 11 Sicilian cultivars, known for their high-quality oil. Differences in virulence were detected among strains and their pathogenicity to the cultivars. The C. acutatum isolates were more virulent than those of C. gloeosporioides or C. cigarro. The Sicilian olive cultivars Cavaliera, Carolea, Calatina, and Nocellara del Belice were the most susceptible to the pathogen, while the cultivars Biancolilla and Nocellara Etnea were the most tolerant. Cultivar response under field conditions showed that anthracnose severity and fruit-rot incidence were positively correlated. This is the first report of C. acutatum and C. cigarro affecting olive trees in Sicily. Control measures for anthracnose depend on accurate characterization of the etiological agents and host cultivar resistance
The structural connectome constrains fast brain dynamics
Brain activity during rest displays complex, rapidly evolving patterns in space and time. Structural connections comprising the human connectome are hypothesized to impose constraints on the dynamics of this activity. Here, we use magnetoencephalography (MEG) to quantify the extent to which fast neural dynamics in the human brain are constrained by structural connections inferred from diffusion MRI tractography. We characterize the spatio-temporal unfolding of whole-brain activity at the millisecond scale from source-reconstructed MEG data, estimating the probability that any two brain regions will significantly deviate from baseline activity in consecutive time epochs. We find that the structural connectome relates to, and likely affects, the rapid spreading of neuronal avalanches, evidenced by a significant association between these transition probabilities and structural connectivity strengths (r = 0.37, p<0.0001). This finding opens new avenues to study the relationship between brain structure and neural dynamics
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