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We compute the two-loop corrections to the helicity amplitudes for the coupling of a massive vector boson to a massless quark-antiquark pair and a gluon, accounting for vector and axial-vector couplings of the vector boson and distinguishing isospin non-singlet and singlet contributions. A new four-dimensional basis for the decomposition of the amplitudes into 12 invariant tensor structures is introduced. The associated form factors are then computed up to two loops in QCD using dimensional regularization. After performing renormalization and infrared subtraction, the finite parts of the renormalized non-singlet vector and axial-vector form factors are shown agree with each other, and to reproduce the previously known two-loop amplitudes. The singlet axial-vector amplitude receives a contribution from the axial anomaly from two loops onwards. This amplitude is computed for massless and massive internal quarks. Our results provide the last missing two-loop amplitudes entering the NNLO QCD corrections of vector-boson-plus-jet production at hadron colliders.

Journal of high energy physics : JHEP (6), 115 (2022). doi:10.1007/JHEP06(2022)115, Published by Springer, Berlin ; Heidelberg

We compute the two-loop massless QCD corrections to the helicity amplitudes for the production of two massive vector bosons in quark-antiquark annihilation, allowing for an arbitrary virtuality of the vector bosons: q q ¯ ′ → V 1 V 2 qq¯′→V1V2 . Combining with the leptonic decay currents, we obtain the full two-loop QCD description of the corresponding electroweak four-lepton production processes. The calculation is performed by projecting the two-loop diagrams onto an appropriate basis of Lorentz structures. All two-loop Feynman integrals are reduced to a basis of master integrals, which are then computed using the differential equations method and optimised for numerical performance. We provide a public C++ code which allows for fast and precise numerical evaluations of the amplitudes.

SummaryFactors predicting family history (FH) of premature arterial thrombosis in young patients with ischaemic stroke (IS) have not been extensively investigated, and whether they might influence the risk of post-stroke recurrence is still unknown. In the present study we analysed 1,881 consecutive first-ever IS patients aged 18–45 years recruited from January 2000 to January 2012 as part of the Italian Project on Stroke in Young Adults (IPSYS). FH of premature arterial thrombosis was any thrombotic event [IS, myocardial infarction or other arterial events event] > 45 years in proband’s first-degree relatives. Compared with patients without FH of premature arterial thrombosis, those with FH (n= 85) were more often smokers (odds ratio [OR], 1.94; 95 % confidence interval [CI], 1.21–3.09) and carriers of procoagulant abnormalities (OR, 3.66; 95 % CI, 2.21–6.06). Smoking (OR, 2.48; 95 % CI, 1.20–5.15), the A1691 mutation in factor V gene (OR, 3.64; 95 % CI, 1.31–10.10), and the A20210 mutation in the prothrombin gene (OR, 8.40; 95 % CI 3.35–21.05) were associated with FH of premature stroke (n = 33), while circulating anti-phospholipids to FH of premature myocardial infarction (n = 45; OR, 3.48; 95 % CI, 1.61–7.51). Mean follow-up time was 46.6 ± 38.6 months. Recurrent events occurred more frequently in the subgroup of patients with FH of premature stroke [19.4 %); p = 0.051] compared to patients without such a FH. In conclusion, young IS patients with FH of premature arterial thrombosis exhibit a distinct risk-factor profile, an underlying procoagulant state and have worse vascular prognosis than those with no FH of juvenile thrombotic events.

Charged gauge boson pair production at the Large Hadron Collider allows detailed probes of the fundamental structure of electroweak interactions. We present precise theoretical predictions for on-shell W+ W- production that include, for the first time, QCD effects up to next to next to leading order in perturbation theory. As compared to next to leading order, the inclusive W+ W- cross section is enhanced by 9% at 7 TeV and 12% at 14 TeV. The residual perturbative uncertainty is at the 3% level. The severe contamination of the W+ W- cross section due to top-quark resonances is discussed in detail. Comparing different definitions of top-free W+ W- production in the four and five flavor number schemes, we demonstrate that top-quark resonances can be separated from the inclusive W+ W- cross section without a significant loss of theoretical precision.

Background— Data on long-term risk and predictors of recurrent thrombotic events after ischemic stroke at a young age are limited. Methods and Results— We followed 1867 patients with first-ever ischemic stroke who were 18 to 45 years of age (mean age, 36.8±7.1 years; women, 49.0%), as part of the Italian Project on Stroke in Young Adults (IPSYS). Median follow-up was 40 months (25th to 75th percentile, 53). The primary end point was a composite of ischemic stroke, transient ischemic attack, myocardial infarction, or other arterial events. One hundred sixty-three patients had recurrent thrombotic events (average rate, 2.26 per 100 person-years at risk). At 10 years, cumulative risk was 14.7% (95% confidence interval, 12.2%–17.9%) for primary end point, 14.0% (95% confidence interval, 11.4%–17.1%) for brain ischemia, and 0.7% (95% confidence interval, 0.4%–1.3%) for myocardial infarction or other arterial events. Familial history of stroke, migraine with aura, circulating antiphospholipid antibodies, discontinuation of antiplatelet and antihypertensive medications, and any increase of 1 traditional vascular risk factor were independent predictors of the composite end point in multivariable Cox proportional hazards analysis. A point-scoring system for each variable was generated by their β-coefficients, and a predictive score (IPSYS score) was calculated as the sum of the weighted scores. The area under the receiver operating characteristic curve of the 0- to 5-year score was 0.66 (95% confidence interval, 0.61–0.71; mean, 10-fold internally cross-validated area under the receiver operating characteristic curve, 0.65). Conclusions— Among patients with ischemic stroke aged 18 to 45 years, the long-term risk of recurrent thrombotic events is associated with modifiable, age-specific risk factors. The IPSYS score may serve as a simple tool for risk estimation.

In patients with ischemic stroke, endovascular treatment results in a higher rate of recanalization of the affected cerebral artery than systemic intravenous thrombolytic therapy. However, comparison of the clinical efficacy of the two approaches is needed.We randomly assigned 362 patients with acute ischemic stroke, within 4.5 hours after onset, to endovascular therapy (intraarterial thrombolysis with recombinant tissue plasminogen activator [t-PA], mechanical clot disruption or retrieval, or a combination of these approaches) or intravenous t-PA. Treatments were to be given as soon as possible after randomization. The primary outcome was survival free of disability (defined as a modified Rankin score of 0 or 1 on a scale of 0 to 6, with 0 indicating no symptoms, 1 no clinically significant disability despite symptoms, and 6 death) at 3 months.A total of 181 patients were assigned to receive endovascular therapy, and 181 intravenous t-PA. The median time from stroke onset to the start of treatment was 3.75 hours for endovascular therapy and 2.75 hours for intravenous t-PA (P0.001). At 3 months, 55 patients in the endovascular-therapy group (30.4%) and 63 in the intravenous t-PA group (34.8%) were alive without disability (odds ratio adjusted for age, sex, stroke severity, and atrial fibrillation status at baseline, 0.71; 95% confidence interval, 0.44 to 1.14; P=0.16). Fatal or nonfatal symptomatic intracranial hemorrhage within 7 days occurred in 6% of the patients in each group, and there were no significant differences between groups in the rates of other serious adverse events or the case fatality rate.The results of this trial in patients with acute ischemic stroke indicate that endovascular therapy is not superior to standard treatment with intravenous t-PA. (Funded by the Italian Medicines Agency, ClinicalTrials.gov number, NCT00640367.).

Background Early highly active antiretroviral therapy (HAART), started within the first months of age, has been proven to be the optimal strategy to prevent immunological and clinical deterioration in perinatally HIV-infected children. Nevertheless, data about long-term follow-up of early treated children are lacking. Methods We report data from 40 perinatally HIV-infected-children receiving early HAART, with a median follow-up period of 5.96 years (interquartile range [IQR]:4.21–7.62). Children were enrolled at birth in the Italian Register for HIV Infection in Children. Comparison with 91 infected children born in the same period, followed-up from birth, and receiving deferred treatment was also provided. Results Nineteen children (47.5%) were still receiving their first HAART regimen at last follow-up. In the remaining children the first regimen was discontinued, after a median period of 3.77 years (IQR: 1.71–5.71) because of viral failure (8 cases), liver toxicity (1 case), structured therapy interruption (3 cases), or simplification/switch to a PI-sparing regimen (9 cases). Thirty-nine (97.5%) children showed CD4+ T-lymphocyte values>25%, and undetectable viral load was reached in 31 (77.5%) children at last visit. Early treated children displayed significantly lower viral load than not-early treated children, until 6 years of age, and higher median CD4+ T-lymphocyte percentages until 4 years of age. Twenty-seven (29.7%) not-early treated vs. 0/40 early treated children were in clinical category C at last follow-up (P < 0.0001). Conclusion Our findings suggest that clinical, virologic and immunological advantages from early-HAART are long-lasting. Recommendations indicating the long-term management of early treated children are needed.

The aim of the present study is to evaluate role of plasma antioxidants (albumin, bilirubin and uric acid) in patients suffering from type I Bipolar Disorder (BD-I) during different phases of illness: acute mania, euthymia and bipolar depression. Medical records of consecutive 110 BD-I patients (38 patients with acute mania, 35 in euthymic state, full remission, and 37 in depressive phase) were reviewed to evaluate plasma antioxidant levels. Laboratory data of 40 healthy controls were also obtained. The scores of Young Mania Rating Scale (YMRS), Bech-Rafaelsen Manic Rating Scale (BRMRS) and Hamilton Rating Scale for Depression (HAM-D) were evaluated. Serum uric acid levels were higher in acute mania than other patient subgroups and healthy controls. Serum uric acid levels directly correlated with BRMRS and YMRS scores. No differences were found between clinical groups during different phases and healthy controls concerning albumin and bilirubin. In conclusion, the results of the present study support the notion that serum uric acid levels may be higher in patients with BP-I (especially during manic phases) which may suggest a dysregulation of the purinergic system. However, limitations should be considered and further studies are needed.

In 1989 HCV was demonstrated to be the leading cause of non-A, non-B hepatitis. Not only HCV is able to determine chronic hepatitis in most patients, often leading to hepatocellular carcinoma, but it has also been shown to be strictly associated with a number of immunologically-mediated diseases. This review focuses on the reported associations between HCV and other diseases and the role that HCV might play in their pathogenesis.