Time-resolved angiography with stochastic trajectories for dynamic contrast-enhanced MRI in head and neck cancer: Are pharmacokinetic parameters affected?

Purpose To investigate the effects of different time-resolved angiography with stochastic trajectories (TWIST) k-space undersampling schemes on calculated pharmacokinetic dynamic contrast-enhanced (DCE) vascular parameters.Methods A digital perfusion phantom was employed to simulate effects of TWIST on characteristics of signal changes in DCE. Furthermore, DCE-MRI was acquired without undersampling in a group of patients with head and neck squamous cell carcinoma and used to simulate a range of TWIST schemes. Errors were calculated as differences between reference and TWIST-simulated DCE parameters. Parametrical error maps were used to display the averaged results from all tumors.Results For a relatively wide range of undersampling schemes, errors in pharmacokinetic parameters due to TWIST were under 10% for the volume transfer constant, Ktrans, and total extracellular extravascular space volume, Ve. TWIST induced errors in the total blood plasma volume, Vp, were the largest observed, and these were inversely dependent on the area of the fully sampled k-space. The magnitudes of errors were not correlated with Ktrans, Vp and weakly correlated with Ve.Conclusions The authors demonstrated methods to validate and optimize k-space view-sharing techniques for pharmacokinetic DCE studies using a range of clinically relevant spatial and temporal patient derived data. The authors found a range of undersampling patterns for which the TWIST sequence can be reliably used in pharmacokinetic DCE-MRI. The parameter maps created in the study can help to make a decision between temporal and spatial resolution demands and the quality of enhancement curve characterization

Search for pair and single production of new heavy quarks that decay to a Z boson and a third-generation quark in pp collisions at √s = 8TeV with the ATLAS detector

A search is presented for the production of new heavy quarks that decay to a Z boson and a third-generation Standard Model quark. In the case of a new charge +2/3 quark (T), the decay targeted is T -> Zt, while the decay targeted for a new charge -1/3 quark (B) is B -> Zb. The search is performed with a dataset corresponding to 20.3 fb(-1) of p p collisions at root s = 8TeV recorded in 2012 with the ATLAS detector at the CERN Large Hadron Collider. Selected events contain a high transverse momentum Z boson candidate reconstructed from a pair of oppositely charged same-flavor leptons (electrons or muons), and are analyzed in two channels defined by the absence or presence of a third lepton. Hadronic jets, in particular those with properties consistent with the decay of a b-hadron, are also required to be present in selected events. Different requirements are made on the jet activity in the event in order to enhance the sensitivity to either heavy quark pair production mediated by the strong interaction, or single production mediated by the electroweak interaction. No significant excess of events above the Standard Model expectation is observed, and lower limits are derived on the mass of vector-like T and B quarks under various branching ratio hypotheses, as well as upper limits on the magnitude of electroweak coupling parameters

Significant benefits of AIP testing and clinical screening in familial isolated and young-onset pituitary tumors

Context Germline mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene are responsible for a subset of familial isolated pituitary adenoma (FIPA) cases and sporadic pituitary neuroendocrine tumors (PitNETs). Objective To compare prospectively diagnosed AIP mutation-positive (AIPmut) PitNET patients with clinically presenting patients and to compare the clinical characteristics of AIPmut and AIPneg PitNET patients. Design 12-year prospective, observational study. Participants & Setting We studied probands and family members of FIPA kindreds and sporadic patients with disease onset ≤18 years or macroadenomas with onset ≤30 years (n = 1477). This was a collaborative study conducted at referral centers for pituitary diseases. Interventions & Outcome AIP testing and clinical screening for pituitary disease. Comparison of characteristics of prospectively diagnosed (n = 22) vs clinically presenting AIPmut PitNET patients (n = 145), and AIPmut (n = 167) vs AIPneg PitNET patients (n = 1310). Results Prospectively diagnosed AIPmut PitNET patients had smaller lesions with less suprasellar extension or cavernous sinus invasion and required fewer treatments with fewer operations and no radiotherapy compared with clinically presenting cases; there were fewer cases with active disease and hypopituitarism at last follow-up. When comparing AIPmut and AIPneg cases, AIPmut patients were more often males, younger, more often had GH excess, pituitary apoplexy, suprasellar extension, and more patients required multimodal therapy, including radiotherapy. AIPmut patients (n = 136) with GH excess were taller than AIPneg counterparts (n = 650). Conclusions Prospectively diagnosed AIPmut patients show better outcomes than clinically presenting cases, demonstrating the benefits of genetic and clinical screening. AIP-related pituitary disease has a wide spectrum ranging from aggressively growing lesions to stable or indolent disease course

Measurement of inclusive jet charged-particle fragmentation functions in Pb plus Pb collisions at root S-NN=2.76 TeV with the ATLAS detector

© 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/license/by/3.0/). Funded by SCOAP3

Centrality evolution of the charged-particle pseudorapidity density over a broad pseudorapidity range in Pb-Pb collisions at root s(NN)=2.76TeV

Peer reviewe

Leucemia mielóide aguda t(8;21): freqüência em pacientes brasileiros Acute myeloid leukemia with t(8;21): frequency among Brazilians

A leucemia mielóide aguda (LMA) com diferenciação e t(8;21) ou LMA M2 com t(8;21), pela classificação FAB, tem sido descrita entre 6% e 12% dos casos nas grandes séries. Em nosso meio há poucas descrições com números expressivos de casos. O objetivo do presente trabalho foi avaliar qual a freqüência de t(8;21) dentre 190 casos de LMA, ao diagnóstico. Foram observados 13 (6,8%) casos com t(8;21)(q22;q22), a idade mediana foi de 30 anos (variando de 3 a 64 anos), sendo que seis (46,2%) pacientes tinham menos que 21 anos e relação M:F de 0,8:1 (seis homens e sete mulheres).Acute myeloid leukemia with differentiation and t(8;21) or AML FAB M2 with t(8;21) has been described in from 6% to 12% of the cases in large series. There are very few descriptions with a small number of cases in Brazil. The objective of the present paper is to evaluate the frequency of t(8;21) among 190 cases of AML, at diagnosis. A total of 13 (6,8%) cases with t(8;21) (q22;q22) have been described, with a median age of 30 years (varying from 3 to 64), with six (46,2%) patients younger than 21 years old, and a male to female rate of 0.8:1 (six men to seven women)

Acute promyelocytic leukemia with t(15;17): frequency of additional clonal chromosome abnormalities and FLT3 mutations

Universidade Federal de São Paulo, Dept Hematol, São Paulo, BrazilFleury Inst, Dept Hematol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Hematol, São Paulo, BrazilWeb of Scienc

Deletion of 17p13 and LIS1 gene mutation in isolated lissencephaly sequence

Classical lissencephaly is a neuroblast migration disorder that occurs either as isolated lissencephaly sequence or in association with malformation syndromes, such as the Miller-Dieker syndrome. in this work, alterations of the LIS1 gene in patients diagnosed as having isolated lissencephaly sequence were investigated. Ten patients were evaluated for the following aspects: classical cytogenetics by karyotyping using solid staining and G-banding; molecular cytogenetics using fluorescent in situ hybridization with a specific probe for the critical region of isolated lissencephaly sequence; and molecular analysis using deoxyribonucleic acid sequencing. Classical cytogenetic analysis indicated apparently normal karyotypes in all patients, but fluorescent in situ hybridization revealed a 17p13.3 microdeletion in one. in another patient, deoxyribonucleic acid sequencing disclosed a 1 base pair insertion in exon 4 within a sequence of eight consecutive adenine residues (162-163insA), a mutation that predicts a truncated protein. Two different polymorphisms were also detected: a T > C substitution in intron 6 (c.568 + 27bp T > C) and a C > T substitution in the nontranslated region of exon 11 (1250 C > T). These results indicate that cytogenetic analysis and molecular investigation of the LIS1 gene are not always sufficient to determine the disease etiology. These findings are consistent with previous studies and suggest the involvement of other genes in cortical malformation. (c) 2006 by Elsevier Inc. All rights reserved.Universidade Federal de São Paulo, Dept Morfol, Disciplina Genet, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Diagnost Imagen, BR-04023900 São Paulo, BrazilUniv Cuiaba, Fac Med, Disciplina Embriol, Cuiaba, BrazilUniversidade Federal de São Paulo, Dept Morfol, Disciplina Genet, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Microbiol Imunol & Parasitol, BR-04023900 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Diagnost Imagen, BR-04023900 São Paulo, BrazilWeb of Scienc