207 research outputs found
Online assessment of negotiation skills through 3D role play simulation
The lack of standardised technological tools to assess psychological characteristics allows traditional tests to be still widely used, though these tests require double processing and expensive procedures. ENACT is both a serious game for a standardised assessment of the user negotiation skills and an Intelligent Tutoring System, which makes use of the data collected during the interaction in order to generate a tailored environment for the user to experience and improve their skills and be guided through learning
The frozen elephant trunk technique in acute aortic dissection: the ultimate solution? An institutional experience
ObjectiveAcute aortic dissection remains a serious emergency in the field of cardiovascular medicine and a challenge for cardiothoracic surgeons. In the present study, we seek to compare the outcomes of different surgical techniques in the repair of type A acute aortic dissection.MethodsBetween April 2015 and May 2023, 213 patients (82 women, aged: 63.9 ± 13.3 years) with acute aortic dissection (205 type A and 8 non-A-non-B dissections) underwent surgical treatment in our department. A total of 45 patients were treated with the frozen elephant trunk (FET) technique supported by the Thoraflex™ Hybrid prosthesis, 33 received total aortic arch replacement (TAR)—standard or conventional elephant trunk—treatment, and 135 were treated with hemiarch replacement (HR). Aortic arch surgery was performed in most patients under moderate hypothermic (28°C on average) circulatory arrest, with selective antegrade cerebral perfusion through the right axillary artery.ResultsThe rates of early mortality were 17.8% (38 perioperative deaths) in the whole population, 8.9% in the FET group of patients, and 33% and 17% in the TAR and HR group of patients, respectively (P-value 0.025). The rate of spinal cord injury was 2.3% (five patients), and a paresis of recurrent laryngeal occurred in 3.7% of patients (seven patients, four were treated with FET). Permanent neurological dysfunction occurred in 27 patients (12.7%). After a mean follow-up of 3 years, the rate of mid-term mortality of discharged patients was 19.4% (34 deaths: 7 FET, 4 TAR, and 23 HR) and the overall mortality rate was 33.8% [72 deaths: 11 FET (24.4%); 15 TAR (45.4%); 46 HR (34.1%)]. A total of 8 patients (17.8%) in whom FET was applied received additional endovascular treatment in the descending aorta.ConclusionsIn our institutional experience, we found that the frozen elephant trunk technique with a high-end Thoraflex Hybrid prosthesis proved its surgical suitability in the treatment of acute aortic dissection with favorable outcomes. The FET technique and our perioperative management led to comparable neurological outcomes and reduced mortality rates in these emergency cases
Control angiography for perioperative myocardial Ischemia after coronary surgery: Meta-analysis
Background: Perioperative myocardial ischemia (PMI) in patients undergoing coronary artery bypass grafting (CABG) is associated with poor outcome. The aim of this study was to pool the available data on the outcome after control angiography and repeat revascularization in patients with perioperative myocardial ischemia (PMI) after coronary artery bypass grafting (CABG).Methods: A literature review was performed through PubMed, Scopus, ScienceDirect and Google Scholar to identify studies published since 1990 evaluating the outcome of PMI after CABG.Results: Nine studies included 1104 patients with PMI after CABG and 1056 of them underwent control angiography early after CABG. Pooled early mortality after reoperation for PMI without control angiography was 43.6% (95%CI 29.7-57.6%) and 79.8% of them (95%CI 64.4-95.2%) had an acute graft failure detected at reoperation. Among patients who underwent control angiography for PMI, 31.7% had a negative finding at angiography (95%CI 25.6-37.8%) and 62.1% had an acute graft failure (95%CI 56.6-67.6%). Repeat revascularization was performed after early control angiography in 46.3% of patients (95%CI 39.9-52.6%; 54.2% underwent repeat surgical revascularization; 45.8% underwent percutaneous coronary intervention). Pooled early mortality after control angiography with or without repeat revascularization was 8.9% (95%CI 6.7-11.1%). Three studies reported on early mortality rates which did not differ between repeat surgical revascularization and PCI (11.7% vs. 9.2%, respectively; risk ratio 1.45, 95%CI 0.67-3.11). In these three series, early mortality after conservative treatment was 5.9% (95%CI 3.6-8.2%).Conclusions: Control angiography seems to be a valid life-saving strategy to guide repeat revascularization in hemodynamically stable patients suffering PMI after CABG.</p
Dicer and Drosha expression and response to Bevacizumab-based therapy in advanced colorectal cancer patients
PURPOSE:
The miRNA-regulating enzymes Dicer and Drosha exhibit aberrant expression in several cancer types. Dicer and Drosha play a crucial role during the angiogenetic process in vitro and, for Dicer, in vivo. We aimed to investigate the potential role of Dicer and Drosha in predicting response to Bevacizumab-based therapy in advanced colorectal cancer (CRC) patients.
METHODS:
Dicer and Drosha mRNA levels were analysed in formalin-fixed paraffin-embedded specimens from patients affected by advanced CRC treated with or without Bevacizumab-containing regimens (n=116 and n=50, respectively) and from patients with diverticulosis as control group (n=20). The experimental data were obtained using qRT-PCR, analysed comparing Dicer and Drosha expression levels in tumour samples versus normal mucosa and then compared to clinical outcome.
RESULTS:
The tumour samples from Bevacizumab-treated patients showed a significantly higher Drosha expression (P<.001) versus normal mucosa, while Dicer levels did not differ. Intriguingly, we found that low Dicer levels predicted a longer progression-free survival (PFS) (P<.0001) and overall survival (OS) (P=.009). In addition, low Dicer levels were associated with better response to Bevacizumab-based treatments versus high Dicer levels (1.7% complete responses and 53.4% partial responses versus 0% and 32.7%, respectively; P=.0067). Multivariate analysis identified three independent predictors of improved OS: high performance status (PS) (relative risk (RR) 1.45; P=.011), lower organs involvement (RR 0.79; P=.034) and low Dicer expression (RR 0.71; P=.008). Conversely, Drosha levels were not associated with prognosis and outcome associated with treatment. In non-Bevacizumab-treated patients, Dicer and Drosha expression did not correlate with outcome.
CONCLUSION:
These findings suggest that low Dicer mRNA levels seem to be independent predictors of favourable outcome and response in patients affected by advanced CRCs treated with Bevacizumab-based therapy
The role of macrophages polarization in predicting prognosis of radically resected gastric cancer patients
Tumour-associated Macrophages (TAM) present two different polarizations: classical (M1) characterized by immunostimulation activity and tumour suppression; alternative (M2) characterized by tumour promotion and immune suppression. In this retrospective study, we evaluated the correlation between the two forms of TAM with survival time in radically resected gastric cancer patients. A total of 52 chemo- and radio- naive patients were included. Two slides were prepared for each patient and double-stained for CD68/NOS2 (M1) or CD68/CD163 (M2) and five representative high-power fields per slide were evaluated for TAM count. The median value of the two macrophage populations density and the median value of M1/M2 ratio were used as cut-off. Twenty-seven patients with M1 density above-the-median had a significantly higher survival compared to those below the median. Twenty-six patients with M1/M2 ratio above the median showed median OS of 27.2 months compared to 15.5 months of the patients below the median. No association between M2 macrophage density and patient’s outcome was found. In multivariate analysis, M1/M2 was a positive independent predictor of survival. The M1 macrophage density and M1/M2 ratio, as con- firmed in multivariate analysis, are factors that can help in predicting patients survival time after radical surgery for gastric cancer
Effect of holding equine oocytes in meiosis inhibitor-free medium before in vitro maturation and of holding temperature on meiotic suppression and mitochondrial energy/redox potential
BACKGROUND: Evaluation of mitochondrial function offers an alternative to evaluate embryo development for assessment of oocyte viability, but little information is available on the relationship between mitochondrial and chromatin status in equine oocytes. We evaluated these parameters in immature equine oocytes either fixed immediately (IMM) or held overnight in an Earle’s/Hank’s’ M199-based medium in the absence of meiotic inhibitors (EH treatment), and in mature oocytes. We hypothesized that EH holding may affect mitochondrial function and that holding temperature may affect the efficiency of meiotic suppression. METHODS: Experiment 1 - Equine oocytes processed immediately or held in EH at uncontrolled temperature (22 to 27°C) were evaluated for initial chromatin configuration, in vitro maturation (IVM) rates and mitochondrial energy/redox potential. Experiment 2 - We then investigated the effect of holding temperature (25°C, 30°C, 38°C) on initial chromatin status of held oocytes, and subsequently repeated mitochondrial energy/redox assessment of oocytes held at 25°C vs. immediately-evaluated controls. RESULTS: EH holding at uncontrolled temperature was associated with advancement of germinal vesicle (GV) chromatin condensation and with meiotic resumption, as well as a lower maturation rate after IVM. Holding did not have a significant effect on mitochondrial distribution within chromatin configurations. Independent of treatment, oocytes having condensed chromatin had a significantly higher proportion of perinuclear/pericortical mitochondrial distribution than did other GV configurations. Holding did not detrimentally affect oocyte energy/redox parameters in viable GV-stage oocytes. There were no significant differences in chromatin configuration between oocytes held at 25°C and controls, whereas holding at higher temperature was associated with meiosis resumption and loss of oocytes having the condensed chromatin GV configuration. Holding at 25°C was not associated with progression of mitochondrial distribution pattern and there were no significant differences in oocyte energy/redox parameters between these oocytes and controls. CONCLUSIONS: Mitochondrial distribution in equine GV-stage oocytes is correlated with chromatin configuration within the GV. Progression of chromatin configuration and mitochondrial status during holding are dependent on temperature. EH holding at 25°C maintains meiotic arrest, viability and mitochondrial potential of equine oocytes. This is the first report on the effects of EH treatment on oocyte mitochondrial energy/redox potential
Intercomparison of the northern hemisphere winter mid-latitude atmospheric variability of the IPCC models
We compare, for the overlapping time frame 1962-2000, the estimate of the
northern hemisphere (NH) mid-latitude winter atmospheric variability within the
XX century simulations of 17 global climate models (GCMs) included in the
IPCC-4AR with the NCEP and ECMWF reanalyses. We compute the Hayashi spectra of
the 500hPa geopotential height fields and introduce an integral measure of the
variability observed in the NH on different spectral sub-domains. Only two
high-resolution GCMs have a good agreement with reanalyses. Large biases, in
most cases larger than 20%, are found between the wave climatologies of most
GCMs and the reanalyses, with a relative span of around 50%. The travelling
baroclinic waves are usually overestimated, while the planetary waves are
usually underestimated, in agreement with previous studies performed on global
weather forecasting models. When comparing the results of various versions of
similar GCMs, it is clear that in some cases the vertical resolution of the
atmosphere and, somewhat unexpectedly, of the adopted ocean model seem to be
critical in determining the agreement with the reanalyses. The GCMs ensemble is
biased with respect to the reanalyses but is comparable to the best 5 GCMs.
This study suggests serious caveats with respect to the ability of most of the
presently available GCMs in representing the statistics of the global scale
atmospheric dynamics of the present climate and, a fortiori, in the perspective
of modelling climate change.Comment: 39 pages, 8 figures, 2 table
On the Classification of Residues of the Grassmannian
We study leading singularities of scattering amplitudes which are obtained as
residues of an integral over a Grassmannian manifold. We recursively do the
transformation from twistors to momentum twistors and obtain an iterative
formula for Yangian invariants that involves a succession of dualized twistor
variables. This turns out to be useful in addressing the problem of classifying
the residues of the Grassmannian. The iterative formula leads naturally to new
coordinates on the Grassmannian in terms of which both composite and
non-composite residues appear on an equal footing. We write down residue
theorems in these new variables and classify the independent residues for some
simple examples. These variables also explicitly exhibit the distinct solutions
one expects to find for a given set of vanishing minors from Schubert calculus.Comment: 20 page
An approach to evaluating the user experience of serious games
The use of serious games to support learning continues to expand across a range of educational and training settings. Hence, a need exists to understand more fully how users experience such games. This study seeks to describe and assess an approach to the evaluation of user-experience applied within the context of a specific serious game developed to address the training needs of people working in social enterprises. Drawing on an extensive literature review, the development of a survey instrument to capture the multi-dimensional nature of user-experience is explained as is the evaluation process employed. Findings from surveys of individuals working in social enterprises are analysed and discussed. The results demonstrate the value of the proposed method of user-experience evaluation. Recommendations for practice and further research are outlined, identifying in particular the importance of qualitative insights in the evaluation process and the need for greater understanding of the inter-relationships between the various dimensions and attributes of user-experience in serious games
Phenomenology of the Higgs effective Lagrangian via FeynRules
The Higgs discovery and the lack of any other hint for new physics favor a description of non-standard Higgs physics in terms of an effective field theory. We present an implementation of a general Higgs effective Lagrangian containing operators up to dimension six in the framework of FeynRules and provide details on the translation between the mass and interaction bases, in particular for three- and four-point interaction vertices involving Higgs and gauge bosons. We illustrate the strengths of this implementation by using the UFO interface of FeynRules capable to generate model files that can be understood by the MadGraph 5 event generator and that have the specificity to contain all interaction vertices, without any restriction on the number of external legs or on the complexity of the Lorentz structures. We then investigate several new physics effects in total rates and differential distributions for different Higgs production modes, including gluon fusion, associated production with a gauge boson and di-Higgs production. We finally study contact interactions of gauge and Higgs bosons to fermions
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