401 research outputs found
Far-from-equilibrium attractors with Full Relativistic Boltzmann approach in boost-invariant and non-boost-invariant systems
We study the universal behavior associated with a Relativistic Boltzmann
Transport (RBT) approach with the full collision integral in 0+1D conformal
systems. We show that all momentum moments of the distribution function exhibit
universal behavior. Furthermore, the RBT approach allows to calculate the full
distribution function, showing that an attractor behavior is present in both
the longitudinal and transverse momentum dependence. We compare our results to
the far-from-equilibrium attractors determined with other approaches, such as
kinetic theory in Relaxation Time Approximation (RTA) and relativistic
hydrodynamic theories, both in their viscous (DNMR) an anisotropic (aHydro)
formulations, finding a very similar evolution, but an even faster
thermalization in RBT for higher order moments. For the first time, we extended
this analysis also to study the attractor behavior under a
temperature-dependent viscosity , accounting also for the rapid
increase toward the hadronic phase. We find that a partial breaking of the
scaling behavior with respect to emerges only at generating a transient deviation from attractors; interestingly this in
realistic finite systems may occur around the freeze-out dynamics. Finally, we
investigate for the first time results beyond the boost-invariant picture,
finding that also in such a case the system evolves toward the universal
attractor. In particular, we present the forward and pull-back attractors at
different space-time rapidities including rapidity regions where initially the
distribution function is even vanishing.Comment: 20 pages, 15 figure
Capsule endoscopy in pediatrics: a 10-years journey.
Video capsule endoscopy (CE) for evaluation the esophagus (ECE), small bowel (SBCE) and the colon (CCE) is particularly useful in pediatrics, because this imaging modality does not require ionizing radiation, deep sedation or general anesthesia. The risk of capsule retention appears to be dependent on indication rather than age and parallels the adult experience by indication, making SBCE a relatively safe procedure with a significant diagnostic yield. The newest indication, assessment of mucosal change, greatly enhances and expands its potential benefit. The diagnostic role of CE extends beyond the SB. The use of ECE also may enhance our knowledge of esophageal disease and assist patient care. Colon CCE is a novel minimally invasive and painless endoscopic technique allowing exploration of the colon without need for sedation, rectal intubation and gas insufflation. The limited data on ECE and CCE in pediatrics does not yet allow the same conclusions regarding efficacy; however, both appear to provide safe methods to assess and monitor mucosal change in their respective areas with little discomfort. Moreover, although experience has been limited, the patency capsule may help lessen the potential of capsule retention; and newly researched protocols for bowel cleaning may further enhance CE's diagnostic yield. However, further research is needed to optimize the use of the various CE procedures in pediatric populations
Fecal and mucosal microbiota profiling in pediatric inflammatory bowel diseases
An altered gut microbiota profile has been widely documented in inflammatory bowel diseases (IBD). The intestinal microbial community has been more frequently investigated in the stools than at the level of the mucosa, while most of the studies have been performed in adults. We aimed to define the gut microbiota profile either by assessing fecal and colonic mucosa samples (inflamed or not) from pediatric IBD patients
Nasopharyngeal tubes in paediatric anaesthesia: is the flow-dependent pressure drop across the tube suitable for calculating oropharyngeal pressure?
Background: Nasopharyngeal tubes (NPTs) are useful in paediatric anaesthesia for insufflating oxygen and anaesthetics. During NPT-anaesthesia, gas insufflation provides some positive oropharyngeal pressure that differs from the proximal airway pressure (Paw) owing to the flow-dependent pressure drop across the NPT (ÎPNPT ).
Aims: This study aimed to investigate whether ÎPNPT could be used for calculating oropharyngeal pressure during NPT-assisted anaesthesia.
Methods: In a physical model of NPT-anaesthesia, using Rohrer's equation, we calculated ÎPNPT for three NPTs (3.5, 4.0, and 5.0, mm inner diameter) under oxygen and several sevoflurane in oxygen combinations in two ventilatory scenarios (continuous positive airway pressure and intermittent positive pressure ventilation). We then calculated oropharyngeal pressure as Paw minus ÎPNPT . Calculated and measured oropharyngeal pressure couples of values were compared with the root mean square deviation (RMSD) to assess accuracy. We also investigated whether oropharyngeal pressure accuracy depends on the NPT diameter, flow rate, gas composition, and leak size. Using ÎPNPT charts, we tested whether ÎPNPT calculation was feasible in clinical practice.
Results: When we tested small-diameter NPTs at high flow or high peak inspiratory pressure, Paw measurements markedly overestimated oropharyngeal pressure. Comparing measured and calculated maximum and minimum oropharyngeal pressure couples yielded RMSDs less than 0.5 cmH2 O regardless of ventilatory modality, NPT diameter, flow rate, gas composition, and leak size.
Conclusion: During NPT-assisted anaesthesia, Paw readings on the anaesthetic monitoring machine overestimate oropharyngeal pressure especially for smaller-diameter NPTs and higher flow, and to a lesser extent for large leaks. Given the importance of calculating oropharyngeal pressure in guiding NPT-ventilation in clinical practice, we propose an accurate calculation using Rohrer's equation method, or approximating oropharyngeal pressure from flow and pressure readings on the anaesthetic machine using the ÎPNPT charts
Directed flow of D mesons at RHIC and LHC: non-perturbative dynamics, longitudinal bulk matter asymmetry and electromagnetic fields
We present a study of the directed flow for mesons discussing both
the impact of initial vorticity and electromagnetic field. Recent studies
predicted that for mesons is expected to be surprisingly much larger
than that of light charged hadrons; we clarify that this is due to a different
mechanism leading to the formation of a directed flow with respect to the one
of the bulk matter at both relativistic and non-relativistic energies. We point
out that the very large for mesons can be generated only if there is
a longitudinal asymmetry between the bulk matter and the charm quarks and if
the latter have a large non-perturbative interaction in the QGP medium. A quite
good agreement with the data of STAR and ALICE is obtained if the diffusion
coefficient able to correctly predict the , and
of meson is employed. Furthermore, the mechanism for the
build-up of the is associated to a quite small formation time that can
be expected to be more sensitive to the initial high-temperature dependence of
the charm diffusion coefficient. We discuss also the splitting of for
and due to the electromagnetic field that is again much larger
than the one observed for charged particles and in agreement with the data by
STAR that have however still error bars comparable with the splitting itself,
while at LHC standard electromagnetic profile assuming a constant conductivity
is not able to account for the huge splitting observed.Comment: 16 pages, 24 figure
Role of age in dynamics of autoantibodies in pediatric celiac disease
Background. Celiac disease (CD) is characterized by elevated serum titers of autoantibodies IgA anti-tissue transglutaminase 2 (TGA-IgA) and IgA anti-endomysial (EMA), with small bowel mucosa atrophy. We evaluated age differences between CD children exhibiting variable antibody titers at diagnosis.MethodsCD children diagnosed between January 2014 and June 2019, according to 2012 ESPGHAN guidelines were studied. All had EMA and TGA-IgA measurements, while a proportion of them underwent esophagogastroduodenoscopy (EGD). Patients were grouped based on serum TGA-IgA titers normalized to the upper limit of normal (ULN) and differences in median age (years) assessed by analysis of variance (ANOVA) and creation of orthogonal contrasts.ResultsCD was diagnosed in 295 subjects (median age: 4.4 [IQR: 2.60-8.52]) with a biopsy sparing protocol (high titer: >= 10xULN) and in 204 by EGD biopsy. Of the latter, 142 (median age: 8.5 [IQR: 5.81-11.06]) and 62 (median age: 9.5 [IQR: 6.26-12.76]) had a low (< 5xULN) and a moderate (>= 5 < 10xULN) TGA-IgA titer, respectively. Potential CD was diagnosed in 20 patients (median age: 3.6 [IQR: 2.47-6.91]). The median age was significantly lower in the no-biopsy group (ANOVA: F-(3,F- 516) = 25.98, p < .001) than in low- and moderate titer groups (p < 0.0001), while there was no statistical difference between biopsy-sparing and potential CD groups.ConclusionCD patients with greatly elevated antibody titers (>= 10xULN) were diagnosed at an earlier age than those with lower titers. This may indicate that an increase in TGA-IgA is independent of age and suggests a polarization of autoimmunity in younger individuals with higher serum antibody levels
Association between elevated TGA-IgA titers and older age at diagnosis with absence of HBV seroconversion in celiac children
Patients with celiac disease can have a low rate of protective hepatitis B (HBV) antibody titers after vaccination. We aimed to evaluate the HBV seroconversion in celiac disease (CD) children at the time of diagnosis as well as to identify the presence of possible predictive factors. Celiac disease children were prospectively enrolled and tested for antibodies against the S protein of HBV (HBsAg) at time of diagnosis between January 2009 and February 2020. Based on the serologic response to the vaccine, ârespondersâ and ânon-respondersâ were identified. Statistical analysis has been performed through R statistical software (3.5.1 version, R core Team) Of 96 CD children evaluated, 41.7% (n = 40) showed non-protective or absent antibody titers against HBV. Elevated IgA-antibodies against transglutaminase 2 (TGA-IgA) values and older age at diagnosis were associated with an absent seroconversion to HBV vaccine, while presenting symptoms were not significant. An elevated prevalence of absent seroconversion to HBV vaccine exists in this cohort of CD patients at the time of disease diagnosis. Elevated TGA-IgA titers and older age at diagnosis seem to negatively predict seroconversion. Further studies are needed to identify the real profile of ânon-respondersâ, aiming to organize surveillance and eventual revaccination strategy
The addition of simvastatin administration to cold storage solution of explanted whole liver grafts for facing ischemia/reperfusion injury in an area with a low rate of deceased donation: a monocentric randomized controlled double-blinded phase 2 study.
BACKGROUND: Liver transplantation is the best treatment for end-stage liver disease. The interruption of the blood supply to the donor liver during cold storage damages the liver, affecting how well the liver will function after transplant. The drug Simvastatin may help to protect donor livers against this damage and improve outcomes for transplant recipients. The aim of this study is to evaluate the benefits of treating the donor liver with Simvastatin compared with the standard transplant procedure.
PATIENT AND METHODS: We propose a prospective, double-blinded, randomized phase 2 study of 2 parallel groups of eligible adult patients. We will compare 3-month, 6-month, and 12-month graft survival after LT, in order to identify a significant relation between the two homogenous groups of LT patients. The two groups only differ by the Simvastatin or placebo administration regimen while following the same procedure, with identical surgical instruments, and medical and nursing skilled staff. To reach these goals, we determined that we needed to recruit 106 patients. This sample size achieves 90% power to detect a difference of 14.6% between the two groups survival using a one-sided binomial test.
DISCUSSION: This trial is designed to confirm the effectiveness of Simvastatin to protect healthy and steatotic livers undergoing cold storage and warm reperfusion before transplantation and to evaluate if the addition of Simvastatin translates into improved graft outcomes.
TRIAL REGISTRATION: ISRCTN27083228
Synthesis and Biological Evaluation of 2-Substituted Benzyl-/Phenylethylamino-4-amino-5-aroylthiazoles as Apoptosis-Inducing Anticancer Agents
Induction of apoptosis is a common chemotherapeutic mechanism to kill cancer cells The thiazole system has been reported over the past decades as a building block for the preparation of anticancer agents. A novel series of 2-arylalkylamino-4-amino-5-(3',4',5'-trimethoxybenzoyl)-thiazole derivatives designed as dual inhibitors of tubulin and cyclin-dependent kinases (CDKs) were synthesized and evaluated for their antiproliferative activity in vitro against two cancer cell lines and, for selected highly active compounds, for interactions with tubulin and cyclin-dependent kinases and for cell cycle and apoptosis effects. Structure-activity relationships were elucidated for various substituents at the 2-position of the thiazole skeleton. Among the synthesized compounds, the most active analogues were found to be the p-chlorobenzylamino derivative 8e as well as the p-chloro and p-methoxyphenethylamino analogues 8f and 8k, respectively, which inhibited the growth of U-937 and SK-MEL-1 cancer cell lines with IC50 values ranging from 5.7 to 12.2 ÎŒM. On U-937 cells, the tested compounds 8f and 8k induced apoptosis in a time and concentration dependent manner. These two latter molecules did not affect tubulin polymerization (IC50 > 20 ÎŒM) nor CDK activity at a single concentration of 10 ÎŒM, suggesting alternative targets than tubulin and CDK for the compounds
The Role of Quantic Molecular Resonance (QMR) in the Treatment of Inferior Turbinate Hypertrophy (ITH): Our Experience With Long-Term Follow-Up in Allergic and Nonallergic Rhinitis Refractory to Medical Therapy. Preliminary Results.
Objective: The aim of this study was to assess the long-term effectiveness of quantic molecular resonance (QMR) in the treatment of inferior turbinate hypertrophy (ITH) in allergic and nonallergic rhinitis refractory to medical therapy. Methods: This study enrolled 281 patients, 160 males (56.9%) and 121 females (43.1%), mean age 37.8 ± 4.1 years, range 18 to 71. Fifty-four patients have been lost to follow up and have been therefore excluded from the final analysis. Based on skin prick test results, 69 patients were considered allergic (group A) and 158 nonallergic (group B). All subjects underwent before surgery (T0) and 3 (T1), 12 (T2), 24 (T3), and 36 months (T4) after QMR treatment to: 4-phase rhinomanometric examination, nasal endoscopy evaluation, and visual analogue scale to quantify the subjective feelings about nasal obstruction. Results: Subjective and objective parameters showed statistically significant improvement in both groups. Group B parameters not changed during follow-up, while group A showed significant worsening between T1 and subsequent assessments. T4 outcome indicates a better result in nonallergic patients. Conclusions: In accordance with the literature, our preliminary data validate QMR treatment as a successful therapeutic option for nasal obstruction due to ITH. Nonallergic patients had a very good T4 outcome. Allergic patients showed a worsening trend after 1 year probably due to other causes
- âŠ