Studies of charm and beauty hadron long-range correlations in pp and pPb collisions at LHC energies

Measurements of the second Fourier harmonic coefficient (v(2)) of the azimuthal distributions of prompt and nonprompt D-0 mesons produced in pp and pPb collisions are presented. Nonprompt D-0 mesons come from beauty hadron decays. The data samples are collected by the CMS experiment at nucleon-nucleon center-of-mass energies of 13 and 8.16 TeV, respectively. In high multiplicity pp collisions, v(2) signals for prompt charm hadrons are reported for the first time, and are found to be comparable to those for light-flavor hadron species over a transverse momentum (pT) range of 2-6 GeV. Compared at similar event multiplicities, the prompt D-0 meson v(2) values in pp and pPb collisions are similar in magnitude. The v(2) values for open beauty hadrons are extracted for the first time via nonprompt D-0 mesons in pPb collisions. For pT in the range of 2-5 GeV, the results suggest that v(2) for nonprompt D-0 mesons is smaller than that for prompt D-0 mesons. These new measurements indicate a positive charm hadron v(2) in pp collisions and suggest a mass dependence in v(2) between charm and beauty hadrons in the pPb system. These results provide insights into the origin of heavy-flavor quark collectivity in small systems. (C) 2020 The Author(s). Published by Elsevier B.V.Peer reviewe

Performance of the CMS Level-1 trigger in proton-proton collisions at √s = 13 TeV

Peer reviewe

Performance of the CMS Level-1 trigger in proton-proton collisions at √s = 13 TeV

At the start of Run 2 in 2015, the LHC delivered proton-proton collisions at a center-of-mass energy of 13\TeV. During Run 2 (years 2015–2018) the LHC eventually reached a luminosity of 2.1× 10$^{34}$ cm$^{-2}$s$^{-1}$, almost three times that reached during Run 1 (2009–2013) and a factor of two larger than the LHC design value, leading to events with up to a mean of about 50 simultaneous inelastic proton-proton collisions per bunch crossing (pileup). The CMS Level-1 trigger was upgraded prior to 2016 to improve the selection of physics events in the challenging conditions posed by the second run of the LHC. This paper describes the performance of the CMS Level-1 trigger upgrade during the data taking period of 2016–2018. The upgraded trigger implements pattern recognition and boosted decision tree regression techniques for muon reconstruction, includes pileup subtraction for jets and energy sums, and incorporates pileup-dependent isolation requirements for electrons and tau leptons. In addition, the new trigger calculates high-level quantities such as the invariant mass of pairs of reconstructed particles. The upgrade reduces the trigger rate from background processes and improves the trigger efficiency for a wide variety of physics signals

Association of Variants in the SPTLC1 Gene With Juvenile Amyotrophic Lateral Sclerosis

Importance: Juvenile amyotrophic lateral sclerosis (ALS) is a rare form of ALS characterized by age of symptom onset less than 25 years and a variable presentation.Objective: To identify the genetic variants associated with juvenile ALS.Design, Setting, and Participants: In this multicenter family-based genetic study, trio whole-exome sequencing was performed to identify the disease-associated gene in a case series of unrelated patients diagnosed with juvenile ALS and severe growth retardation. The patients and their family members were enrolled at academic hospitals and a government research facility between March 1, 2016, and March 13, 2020, and were observed until October 1, 2020. Whole-exome sequencing was also performed in a series of patients with juvenile ALS. A total of 66 patients with juvenile ALS and 6258 adult patients with ALS participated in the study. Patients were selected for the study based on their diagnosis, and all eligible participants were enrolled in the study. None of the participants had a family history of neurological disorders, suggesting de novo variants as the underlying genetic mechanism.Main Outcomes and Measures: De novo variants present only in the index case and not in unaffected family members.Results: Trio whole-exome sequencing was performed in 3 patients diagnosed with juvenile ALS and their parents. An additional 63 patients with juvenile ALS and 6258 adult patients with ALS were subsequently screened for variants in the SPTLC1 gene. De novo variants in SPTLC1 (p.Ala20Ser in 2 patients and p.Ser331Tyr in 1 patient) were identified in 3 unrelated patients diagnosed with juvenile ALS and failure to thrive. A fourth variant (p.Leu39del) was identified in a patient with juvenile ALS where parental DNA was unavailable. Variants in this gene have been previously shown to be associated with autosomal-dominant hereditary sensory autonomic neuropathy, type 1A, by disrupting an essential enzyme complex in the sphingolipid synthesis pathway.Conclusions and Relevance: These data broaden the phenotype associated with SPTLC1 and suggest that patients presenting with juvenile ALS should be screened for variants in this gene.</p

Genome-wide Analyses Identify KIF5A as a Novel ALS Gene

To identify novel genes associated with ALS, we undertook two lines of investigation. We carried out a genome-wide association study comparing 20,806 ALS cases and 59,804 controls. Independently, we performed a rare variant burden analysis comparing 1,138 index familial ALS cases and 19,494 controls. Through both approaches, we identified kinesin family member 5A (KIF5A) as a novel gene associated with ALS. Interestingly, mutations predominantly in the N-terminal motor domain of KIF5A are causative for two neurodegenerative diseases: hereditary spastic paraplegia (SPG10) and Charcot-Marie-Tooth type 2 (CMT2). In contrast, ALS-associated mutations are primarily located at the C-terminal cargo-binding tail domain and patients harboring loss-of-function mutations displayed an extended survival relative to typical ALS cases. Taken together, these results broaden the phenotype spectrum resulting from mutations in KIF5A and strengthen the role of cytoskeletal defects in the pathogenesis of ALS.Peer reviewe

Neoplastic Pericardial Effusion: A Monocentric Retrospective Study

Background: Neoplastic pericardial effusion (NPE) is a life-threatening condition that can worsen clinical outcome in cancer patients. The optimal management of NPE has yet to be defined because randomized studies are lacking. Objective: We report a retrospective monoinstitutional experience describing characteristics, management and prognostic factors in NPE patients. Design: We reviewed clinical, pathological, and echocardiographic features, therapeutic strategies, and outcome in NPE patients referred to our institute from August 2011 to December 2017. Measurements: Twenty-nine patients with NPE from solid tumors have been identified: 21 lung, 5 breast, and 3 other cancer patients. Results: Median age was 62 years. Most of the patients had Eastern Cooperative Oncology Group (ECOG) performance status (PS) 652 (69%) and a symptomatic NPE (69%). In 52% of patients NPE was detected at first diagnosis of metastatic disease, and in 20% of patients pericardium was the only site of metastases. Most of the patients (62%) received systemic therapy, 28% received combined locoregional and systemic therapy, and 10% received locoregional therapy alone. Median overall survival (OS) from NPE diagnosis was 3.9 months. Patients with PS 652 had worse OS than patients with better PS <2 (hazard ratio [HR] 3.56, IC 95% 1.19-10.65, p 0.02). Older age, extrapericardial disease, and NPE at progression showed a trend of association with worse OS. Patients treated with locoregional therapy alone showed the shortest median OS (p 0.05). Conclusions: NPE is related to dismal prognosis. Poor PS significantly worsens survival and influences therapeutic approaches. Randomized studies are required to investigate prognostic factors and appropriate clinical management for patients with NPE

CLINICAL POLICIES ON THE MANAGEMENT OF CHRONIC KIDNEY DISEASE PATIENTS IN ITALY

BACKGROUND: Recent studies have indicated that the implementation of international guidelines for the management of renal patients is suboptimal in Italy. The Italian Society of Nephrology (SIN) decided to undertake a multicentre study to obtain a clear picture of clinical policies on chronic kidney disease (CKD) in Italy. METHODS: A 76-item structured questionnaire, designed to evaluate the organization of clinical care, was administered to the director of each participating centre, within the context of a large observational trial in 100 Italian nephrology centres, collecting information on newly diagnosed CKD patients (K/DOQI stage 3-5) on conservative treatment. This paper reports the questionnaire results related to management of anaemia and bone metabolism disorders; assessment of renal function; creation of a vascular access for dialysis and referral of patients to a nephrologist. RESULTS: Clinical policies at the centre level deviated from guideline recommendations in 70% (timing of vascular access creation) to 25% (assessment of iron deficiency) of centres. Assessment of renal function differed from the recommended approach in 30% of centres; clinical policies related to anaemia and bone disease did not coincide with guideline standards in 50 and 40% of centres, respectively. Directors of renal unit estimates indicate that the creation of a vascular access occurs very late in 38% of patients and that referral to a nephrologist is late in approximately 40% of cases. CONCLUSION: This survey in Italy highlights important deviations of clinical policies at the centre level from guideline recommendations