Determination of the top-quark mass using top-antitop cross section measurements at LHC

Lo studio della fisica del quark top rappresenta un campo in continuo sviluppo da partedella comunità teorica ed è di grande interesse all’interno del programma di fisica sperimentale ad ATLAS. In questa tesi, la massa del quark top è estratta mediante il confronto di calcoli di QCD della sezione d’urto totale e differenziale della produzione top-antitop in collisioni protone-protone ad energia del centro di massa di √s= 13 TeV, prodotti con il programma MATRIX al next-to-next-to-leading order, con dati sperimentali da collisioni pp a √s= 13 TeV raccolti nel 2015 e nel 2016 dal detector ATLAS al Large Hadron Collider (LHC) del CERN, corrispondenti a una luminosità integrata di 36.1 fb−1. Utilizzando la sezione d’urto totale top-antitop (t ̄t) misurata in eventi dileptonicieμe conducendo un’analisi basata su un approccio Bayesiano che utilizza Markov Chain Monte Carlo (MCMC), il valore ottenuto per la massa del quark top è m_t=(174.4+1.7−2.7) GeV. Dal confronto delle predizioni teoriche per la sezione d’urto differenziale assoluta in funzione della massa invariante (m_t ̄t) con dati misurati nel canale leptoni + jet a livello partonico, una seconda estrazione della massa del quark top ha portato al valore m_t= (171.9+3.0−2.9) GeV, ottenuto analizzando il χ2 tra i valori della predizione e quelli misurati

Implantation of atrial flow regulator devices in patients with congenital heart disease and children with severe pulmonary hypertension or cardiomyopathy—an international multicenter case series

BackgroundThe Occlutech Atrial Flow Regulator (AFR) is a self-expandable double-disc nitinol device with a central fenestration. Its use has been approved in the adult population with heart failure and described for pulmonary hypertension (PH). Only case reports and small series have been published about its use in the paediatric population and for congenital heart disease (CHD).ObjectivesThe authors sought to investigate the feasibility, safety, and short-term follow-up of AFR implantation in patients with CHD or children with PH or cardiomyopathy.MethodsThis is a multicenter retrospective study involving 10 centers worldwide. Patients of any age with CHD or patients aged < 18 years with PH or cardiomyopathy needing AFR implantation were included.ResultsA total of 40 patients underwent AFR implantation. The median age of the population at the time of the procedure was 58.5 months (IQR: 31.5–142.5) and the median weight was 17 kg (IQR: 10–46). A total of 26 (65.0%) patients had CHD, nine (22.5%) children, a cardiomyopathy, and five (12.5%), a structurally normal heart. The implantation success rate was 100%. There were two early and one late device thrombosis. Two patients (5.0%) with dilated cardiomyopathy on extracorporeal membrane oxygenator (ECMO) died during the hospital stay. At a median follow-up of 330 days (IQR: 125–593), 37 (92.5%) patients were alive. At follow-up, 20 patients improved their New York Heart Association (NYHA) class, 12 patients did not change their NYHA class, and one patient with idiopathic PH worsened.ConclusionsAFR implantation in patients with CHD and children with severe PH or cardiomyopathy is promising and seems to have beneficial effects at short-term follow-up

Hemodynamic impact of pulmonary vasodilators on single ventricle physiology

IntroductionThe Fontan procedure is the palliative procedure for single ventricle physiology. Pulmonary resistance plays a key role in the success of this operation. There are conflicting data concerning the impact of pulmonary vasodilators on survival and functional capacity among Fontan patients. AimThe aim of this retrospective, single-center, nonrandomized study was to investigate the potential effect of pulmonary vasodilators on pulmonary vasculature in Fontan patients. MethodTwenty-seven patients with single ventricle physiology were enrolled. Eighteen patients were treated with pulmonary vasodilators: 9 patients after Glenn procedure or just after the Fontan completion (Group A) and 9 patients >5years after Fontan completion (Group B). Nine patients after Glenn procedure were enrolled as a control group (Group C). The primary endpoint was to assess changes in hemodynamic profile and pulmonary branches' diameter after 2 right heart catheterizations. Adverse events were recorded. ResultsMean ageSD was 3.2 +/- 1.5years (Group A), 26.8 +/- 12.7years (Group B), and 3.1 +/- 1.0years (Group C). Patients included in Group A had reduced arterial compliance (34.3 +/- 15.4 vs 52.2 +/- 24.2mm(2)/[m(2)*mmHg]; P=.03) at baseline compared with Group C. After treatment, Nakata index and pulmonary compliance increased in patients treated with pulmonary vasodilators (Group A), while remaining stable in the control group (Nakata index: +26 +/- 24% vs -8 +/- 17%, P=.003; pulmonary compliance +80 +/- 49% vs -5 +/- 30%, P=.001). Similar results were found in Group B (Nakata index: pre168.6 +/- 70.7mm(2)/m(2); post204.9 +/- 97.5mm(2)/m(2); P=.026). ConclusionsPulmonary vasodilators reduce pulmonary artery resistance and increase vascular compliance, pulmonary artery diameter, and cardiac output in Fontan patients. Therefore, pulmonary vasodilators may be used before the Fontan procedure in patients at high risk of Fontan procedure failure

Hemodynamic impact of pulmonary vasodilators on single ventricle physiology.

Introduction The Fontan procedure is the palliative procedure for single ventricle physiology. Pulmonary resistance plays a key role in the success of this operation. There are conflicting data concerning the impact of pulmonary vasodilators on survival and functional capacity among Fontan patients. Aim The aim of this retrospective, single-center, nonrandomized study was to investigate the potential effect of pulmonary vasodilators on pulmonary vasculature in Fontan patients. Method Twenty-seven patients with single ventricle physiology were enrolled. Eighteen patients were treated with pulmonary vasodilators: 9 patients after Glenn procedure or just after the Fontan completion (Group A) and 9 patients >5 years after Fontan completion (Group B). Nine patients after Glenn procedure were enrolled as a control group (Group C). The primary endpoint was to assess changes in hemodynamic profile and pulmonary branches' diameter after 2 right heart catheterizations. Adverse events were recorded. Results Mean age ± SD was 3.2 ± 1.5 years (Group A), 26.8 ± 12.7 years (Group B), and 3.1 ± 1.0 years (Group C). Patients included in Group A had reduced arterial compliance (34.3 ± 15.4 vs 52.2 ± 24.2 mm2 /[m2 *mm Hg]; P = .03) at baseline compared with Group C. After treatment, Nakata index and pulmonary compliance increased in patients treated with pulmonary vasodilators (Group A), while remaining stable in the control group (Nakata index: +26 ± 24% vs -8 ± 17%, P = .003; pulmonary compliance +80 ± 49% vs -5 ± 30%, P = .001). Similar results were found in Group B (Nakata index: pre-168.6 ± 70.7 mm2 /m2 ; post-204.9 ± 97.5 mm2 /m2 ; P = .026). Conclusions Pulmonary vasodilators reduce pulmonary artery resistance and increase vascular compliance, pulmonary artery diameter, and cardiac output in Fontan patients. Therefore, pulmonary vasodilators may be used before the Fontan procedure in patients at high risk of Fontan procedure failure

Failed conservative management of a case of aplasia cutis congenita in a low-income country

Aplasia cutis congenita is a rare disease characterized by absence of skin layers. Usually the scalp is affected, but the whole body can be involved. We report extensive aplasia of a baby born of a HIV-positive mother taking antiretroviral drugs. Conservative treatment was not enough to ensure her survival

Parametric response maps of perfusion MRI may identify recurrent glioblastomas responsive to bevacizumab and irinotecan.

Perfusion weighted imaging (PWI) can be used to measure key aspects of tumor vascularity in vivo and recent studies suggest that perfusion imaging may be useful in the early assessment of response to angiogenesis inhibitors. Aim of this work is to compare Parametric Response Maps (PRMs) with the Region Of Interest (ROI) approach in the analysis of tumor changes induced by bevacizumab and irinotecan in recurrent glioblastomas (rGBM), and to evaluate if changes in tumor blood volume measured by perfusion MRI may predict clinical outcome.42 rGBM patients with KPS ≥ 50 were treated until progression, as defined by MRI with RANO criteria. Relative cerebral blood volume (rCBV) variation after 8 weeks of treatment was calculated through semi-automatic ROI placement in the same anatomic region as in baseline. Alternatively, rCBV variations with respect to baseline were calculated into the evolving tumor region using a voxel-by-voxel difference. PRMs were created showing where rCBV significantly increased, decreased or remained unchanged.An increased blood volume in PRM (PRMCBV+) higher than 18% (first quartile) after 8 weeks of treatment was associated with increased progression free survival (PFS; 24 versus 13 weeks, p = 0.045) and overall survival (OS; 38 versus 25 weeks, p = 0.016). After 8 weeks of treatment ROI analysis showed that mean rCBV remained elevated in non responsive patients (4.8 ± 0.9 versus 5.1 ± 1.2, p = 0.38), whereas decreased in responsive patients (4.2 ± 1.3 versus 3.8 ± 1.6 p = 0.04), and re-increased progressively when patients approached tumor progression.Our data suggest that PRMs can provide an early marker of response to antiangiogenic treatment and warrant further confirmation in a larger cohort of GBM patients

Chronic Heart Failure in Children: State of the Art and New Perspectives

Pediatric heart failure (HF) is an important clinical condition with high morbidity and mortality. Compared to adults, pediatric HF shows different etiologies characterized by different physiology, a different clinical course, and deeply different therapeutic approaches. In the last few years, new drugs have been developed and new therapeutic strategies have been proposed with the goal of identifying an individualized treatment regimen. The aim of this article is to review the new potential drugs and non-pharmacological therapies for pediatric heart failure in children

Teenage pregnancies in Mozambique: the experience of “Servicios Amigos dos Adolescentes” clinics in Beira

The purpose of this article is to provide insights into the demand for pregnancy-related health services by adolescent girls and young women in Mozambique. We analysed the patient registers for the first year of operation (2014) of the Servicios Amigos dos Adolescentes (SAAJ) [Friendly Services for Adolescents] clinics in Beira, Mozambique. These registers provide details of the service demands of, and services provided to the 8 290 adolescent girls and young women who accessed the 6 SAAJ clinics in 2014. Analysis of that record, with disaggregation of the patients according to age (9 years or less; 10â\u80\u9314; 15â\u80\u9319; 20â\u80\u9324; 25 and older), show that 3 021 (36%) were pregnant or had previously been pregnant; most being girls in the 15â\u80\u9319 age band (59%). Being pregnant or having been pregnant previously was associated with dropping out of school. Of all the girls and women, 60% agreed to HIV testing and counselling; the HIV prevalence rate amongst this group was 4â\u80\u935% amongst adolescents and 25% amongst women 25 years and older. A minority of the girls and women who were pregnant or had been pregnant previously agreed to HIV testing and counselling. Notwithstanding the limitations for analysis, the results were alarming: substantially high HIV prevalence rates were indicated (2% amongst 10â\u80\u9314 year old girls; 8% amongst 15â\u80\u9319 year olds; 10% amongst 20â\u80\u9324 year olds; and 28% amongst >24 year olds). The data from the SAAJ clinics and results pertain only to conditions in Beira. However, as the first empirical assessment of pregnancy-related service demand amongst adolescent girls and young women in the country and involving a relatively large sample, we contend that this study affirms the need for expansion of sexual and reproductive health (SRH) services, including HIV services, for adolescent girls and young women in Mozambique

Mid- and Long-Term Atrio-Ventricular Functional Changes in Children after Recovery from COVID-19

Background: Although most children may experience mild to moderate symptoms and do not require hospitalization, there are little data on cardiac involvement in COVID-19. However, cardiac involvement is accurately demonstrated in children with MISC. The objective of this study was to evaluate cardiac mechanics in previously healthy children who recovered from severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in a long-term follow-up by means of two-dimensional speckle-tracking echocardiography (STE). Methods: We analyzed a cohort of 157 paediatric patients, mean age 7.7 ± 4.5 years (age range 0.3–18 years), who had a laboratory-confirmed diagnosis of SARS-CoV-2 infection and were asymptomatic or mildly symptomatic for COVID-19. Patients underwent a standard transthoracic echocardiogram and STE at an average time of 148 ± 68 days after diagnosis and were divided in three follow-up groups (240 days). Patients were compared with 107 (41 females—38%) age- and BSA-comparable healthy controls (CTRL). Results: Left ventricular (LV) global longitudinal strain (post-COVID-19: −20.5 ± 2.9%; CTRL: −21.8 ± 1.7%; p p = NS). Moreover, regional longitudinal strain was significantly reduced in LV apical-wall segments of children with disease onset during the second wave of the COVID-19 pandemic compared to the first wave (second wave: −20.2 ± 2.6%; first wave: −21.2 ± 3.4%; p = 0.048). Finally, peak left atrial systolic strain was within the normal range in the post-COVID-19 group with no significant differences compared to CTRLs. Conclusions: Our study demonstrated for the first time the persistence of LV myocardial deformation abnormalities in previously healthy children with an asymptomatic or mildly symptomatic (WHO stages 0 or 1) COVID-19 course after an average follow-up of 148 ± 68 days. A more significant involvement was found in children affected during the second wave. These findings imply that subclinical LV dysfunction may also be a typical characteristic of COVID-19 infection in children and are concerning given the predictive value of LV longitudinal strain in the general population