452 research outputs found
Unrestrained power and deception in the parable of Silvio Berlusconi
The article investigates the last 20 years of Italian politics through the philosophy of Vasugupta’s Śiva-sūtra and Guy Debord’s La Société du spectacle
Properties of the Force Exerted by Filopodia and Lamellipodia and the Involvement of Cytoskeletal Components
During neuronal differentiation, lamellipodia and filopodia explore the environment in search for the correct path to the axon's final destination. Although the motion of lamellipodia and filopodia has been characterized to an extent, little is known about the force they exert. In this study, we used optical tweezers to measure the force exerted by filopodia and lamellipodia with a millisecond temporal resolution. We found that a single filopodium exerts a force not exceeding 3 pN, whereas lamellipodia can exert a force up to 20 pN. Using metabolic inhibitors, we showed that no force is produced in the absence of actin polymerization and that development of forces larger than 3 pN requires microtubule polymerization. These results show that actin polymerization is necessary for force production and demonstrate that not only do neurons process information, but they also act on their environment exerting forces varying from tenths pN to tens of pN
Invasive versus conservative management in spontaneous coronary artery dissection: A meta-analysis and meta-regression study.
Abstract Background There is a paucity of data regarding the best treatment for spontaneous coronary artery dissection (SCAD). Purpose To compare the prognostic impact of conservative versus invasive treatment in patients with SCAD. Methods We systematically searched the literature for studies evaluating the comparative efficacy and safety of invasive revascularization versus medical therapy for the treatment of SCAD from 1990 to 2019. Random-effect meta-analysis was performed comparing clinical outcomes between the two groups. Results 24 observational studies with 1720 patients were included. After 28±14 months, a conservative approach reduced target vessel revascularization rate compared with invasive treatment (OR=0.50; 95% CI 0.28–0.90; P=0.02). No difference was found regarding all-cause mortality (OR=0.81; 95% CI 0.31–2.08; P=0.66), cardiovascular mortality (OR=0.89; 95% CI 0.15–5.40; P=0.89), myocardial infarction (OR=0.95; 95% CI 0.50–1.81; P=0.87), heart failure (OR 0.96; 95% CI 0.41–2.22; P=0.92) and SCAD recurrence (OR=0.94; 95% CI 0.52–1.72; P=0.85). The meta-regression analysis suggested that male gender, diabetes mellitus, smoking habit, prior coronary artery disease, left main coronary artery involvement and lower ejection fraction at admission are related with higher overall mortality, whereas SCAD recurrence was higher among patients with fibromuscular dysplasia. Conclusion A conservative approach provides similar clinical outcomes and lower target vessel revascularization rates compared to an invasive strategy in the setting of SCAD; therefore, when feasible, it should be preferred in this scenario. Forest plots on the study outcomes Funding Acknowledgement Type of funding source: Non
Prognostic Value of T-Wave Alternans in Patients With Heart Failure Due to Nonischemic Cardiomyopathy Results of the ALPHA Study
ObjectivesThe aim of this study was to assess the prognostic value of T-wave alternans (TWA) in New York Heart Association (NYHA) functional class II/III patients with nonischemic cardiomyopathy and left ventricular ejection fraction (LVEF) ≤40%.BackgroundThere is a strong need to identify reliable risk stratifiers among heart failure candidates for implantable cardioverter-defibrillator (ICD) prophylaxis. T-wave alternans may identify low-risk subjects among post-myocardial infarction patients with depressed LVEF, but its predictive role in nonischemic cardiomyopathy is unclear.MethodsFour hundred forty-six patients were enrolled and followed up for 18 to 24 months. The primary end point was the combination of cardiac death + life-threatening arrhythmias; secondary end points were total mortality and the combination of arrhythmic death + life-threatening arrhythmias.ResultsPatients with abnormal TWA (65%) compared with normal TWA (35%) tests were older (60 ± 13 years vs. 57 ± 12 years), were more frequently in NYHA functional class III (22% vs. 19%), and had a modestly lower LVEF (29 ± 7% vs. 31 ± 7%). Primary end point rates in patients with abnormal and normal TWA tests were 6.5% (95% confidence interval [CI] 4.5% to 9.4%) and 1.6% (95% CI 0.6% to 4.4%), respectively. Unadjusted and adjusted hazard ratios were 4.0 (95% CI 1.4% to 11.4%; p = 0.002) and 3.2 (95% CI 1.1% to 9.2%; p = 0.013), respectively. Hazard ratios for total mortality and for arrhythmic death + life-threatening arrhythmias were 4.6 (p = 0.002) and 5.5 (p = 0.004), respectively; 18-month negative predictive values for the 3 end points ranged between 97.3% and 98.6%.ConclusionsAmong NYHA functional class II/III nonischemic cardiomyopathy patients, an abnormal TWA test is associated with a 4-fold higher risk of cardiac death and life-threatening arrhythmias. Patients with normal TWA tests have a very good prognosis and are likely to benefit little from ICD therapy
Massive thymic hemorrhage and hemothorax occurring in utero
Background: Thymic enlargement is a common and physiological finding in children and neonates' X-rays, but it is usually asymptomatic. Occasionally it can cause respiratory distress. In most cases the aetiology of this expansion remains unclear and it is diagnosed as a thymic hyperplasia. True thymic hyperplasia is defined as a gland expansion, both in size and weight, while maintaining normal microscopic architecture. Often it is a diagnosis of exclusion and prognosis is good. Thymic haemorrhage is an unusual condition related to high foetal and neonatal mortality. Case Presentation: We report a case of spontaneous massive thymic haemorrhage in a newborn developing at birth acute respiratory distress associated with severe bilateral haemothorax. Thymic enlargement was evident after pleural evacuation and confirmed by radiographic, Computed Tomography (CT) images and Magnetic Resonance Imaging (MRI) sequences. The spontaneous resolution of this enlargement seen with CT scan and MRI sequences suggested a thymic haemorrhage; surgery was not necessary. Conclusion: Thymic haemorrhage should be considered in newborn infants with pleural effusion, mediastinal space enlargement and Respiratory Distress
Synthesis of a mesoscale ordered 2D-conjugated polymer with semiconducting properties
2D materials with high charge carrier mobility and tunable electronic band
gaps have attracted intense research effort for their potential use as active
components in nanoelectronics. 2D-conjugated polymers (2DCP) constitute a
promising sub-class due to the fact that the electronic band structure can be
manipulated by varying the molecular building blocks, while at the same time
preserving the key features of 2D materials such as Dirac cones and high charge
mobility. The major challenge for their use in technological applications is to
fabricate mesoscale ordered 2DCP networks since current synthetic routes yield
only small domains with a high density of defects. Here we demonstrate the
synthesis of a mesoscale ordered 2DCP with semiconducting properties and Dirac
cone structures via Ullmann coupling on Au(111). This material has been
obtained by combining rigid azatriangulene precursors and a hot dosing approach
which favours molecular diffusion and reduces the formation of voids in the
network. These results open opportunities for the synthesis of 2DCP Dirac cone
materials and their integration into devices.Comment: 21 pages, 3 figure
Correction of beta-thalassemia major by gene transfer in haematopoietic progenitors of pediatric patients
Beta-thalassemia is a common monogenic disorder due to mutations in the beta-globin gene and gene therapy, based on autologous transplantation of genetically corrected haematopoietic stem cells (HSCs), holds the promise to treat patients lacking a compatible bone marrow (BM) donor. We recently showed correction of murine beta-thalassemia by gene transfer in HSCs with the GLOBE lentiviral vector (LV), expressing a transcriptionally regulated human beta-globin gene. Here, we report successful correction of thalassemia major in human cells, by studying a large cohort of pediatric patients of diverse ethnic origin, carriers of different mutations and all candidates to BM transplantation. Extensive characterization of BM-derived CD34(+) cells before and following gene transfer shows the achievement of high frequency of transduction, restoration of haemoglobin A synthesis, rescue from apoptosis and correction of ineffective erythropoiesis. The procedure does not significantly affect the differentiating potential and the relative proportion of haematopoietic progenitors. Analysis of vector integrations shows preferential targeting of transcriptionally active regions, without bias for cancer-related genes. Overall, these results provide a solid rationale for a future clinical translation
Search for composite and exotic fermions at LEP 2
A search for unstable heavy fermions with the DELPHI detector at LEP is
reported. Sequential and non-canonical leptons, as well as excited leptons and
quarks, are considered. The data analysed correspond to an integrated
luminosity of about 48 pb^{-1} at an e^+e^- centre-of-mass energy of 183 GeV
and about 20 pb^{-1} equally shared between the centre-of-mass energies of 172
GeV and 161 GeV. The search for pair-produced new leptons establishes 95%
confidence level mass limits in the region between 70 GeV/c^2 and 90 GeV/c^2,
depending on the channel. The search for singly produced excited leptons and
quarks establishes upper limits on the ratio of the coupling of the excited
fermio
Search for lightest neutralino and stau pair production in light gravitino scenarios with stau NLSP
Promptly decaying lightest neutralinos and long-lived staus are searched for
in the context of light gravitino scenarios. It is assumed that the stau is the
next to lightest supersymmetric particle (NLSP) and that the lightest
neutralino is the next to NLSP (NNLSP). Data collected with the Delphi detector
at centre-of-mass energies from 161 to 183 \GeV are analysed. No evidence of
the production of these particles is found. Hence, lower mass limits for both
kinds of particles are set at 95% C.L.. The mass of gaugino-like neutralinos is
found to be greater than 71.5 GeV/c^2. In the search for long-lived stau,
masses less than 70.0 to 77.5 \GeVcc are excluded for gravitino masses from 10
to 150 \eVcc . Combining this search with the searches for stable heavy leptons
and Minimal Supersymmetric Standard Model staus a lower limit of 68.5 \GeVcc
may be set for the stau mas
- …