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1.
Ann Surg Oncol ; 2024 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-39034365

RESUMEN

BACKGROUND: Inflammatory breast cancer (IBC) is rare and biologically aggressive. We sought to assess diagnostic and management strategies among the American Society of Breast Surgeons (ASBrS) membership. PATIENTS AND METHODS: An anonymous survey was distributed to ASBrS members from March to May 2023. The survey included questions about respondents' demographics and information related to stage III and IV IBC management. Agreement was defined as a shared response by >80% of respondents. In areas of disagreement, responses were stratified by years in practice, fellowship training, and annual IBC patient volume. RESULTS: The survey was administered to 2337 members with 399 (17.1%) completing all questions and defining the study cohort. Distribution of years in practice was 26.0% 0-10 years, 26.6% 11-20 years and 47.4% > 20 years. Overall, 51.2% reported surgical oncology or breast fellowship training, 69.2% maintain a breast-only practice, and 73.5% treat < 5 IBC cases/year. Agreement was identified in diagnostic imaging, trimodal therapy, and mastectomy with wide skin excision for stage III IBC. Lack of agreement was identified in surgical management of the axilla; respondents with < 10 years in practice or fellowship training were more likely to perform axillary dissection for cN0-N2 stage III IBC. Locoregional management of stage IV IBC was variable. CONCLUSIONS: Among ASBrS members, there is consensus in diagnostic evaluation, treatment sequencing and surgical approach to the breast in stage III IBC. Differences exist in surgical management of the cN0-2 axilla with uptake of de-escalation strategies. Clinical trials are needed to evaluate oncologic safety of de-escalation in this high-risk population.

2.
Ann Surg Oncol ; 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39048903

RESUMEN

BACKGROUND: Axillary dissection is the standard of care for patients with positive sentinel lymph nodes (SLNs) following neoadjuvant systemic therapy. Frozen section can provide intraoperative information regarding the need for axillary dissection during the index operation. However, there are limited data on the utility of frozen section in patients with clinically node-negative (cN0) HER2-positive or triple-negative breast cancer. METHODS: We conducted a single-institution observational cohort study including patients with non-inflammatory, cN0, HER2-positive or triple-negative breast cancer treated with neoadjuvant systemic therapy between 2015 and 2019. We estimated the prevalence of SLN positivity and the diagnostic test characteristics of SLN frozen section. RESULTS: Overall, 662 patients were eligible for inclusion, and 44 patients had one or more positive SLNs (prevalence: 6.6%, 95% confidence interval [CI] 4.9-8.8). There were 490 (74.0%) patients who had intraoperative frozen section, and 19 (3.9%) tested positive among 33 (6.7%) with positive final pathology. Frozen section sensitivity was 57.6% (95% CI 39.2-74.5), specificity was 100% (95% CI 99.2-100), positive predictive value was 100% (95% CI 82.4-100), and negative predictive value was 97.0% (95% CI 95.1-98.4). The sensitivity of frozen section for detection of micrometastases or isolated tumor cells was 35.3% (95% CI 14.2-61.7). CONCLUSION: In patients with cN0 HER2-positive or triple-negative breast cancer who have been treated with neoadjuvant therapy, positive SLNs are uncommon and frozen section sensitivity is modest. Decisions to defer SLN evaluation to final pathology, which may be reasonable in many settings, can be informed, in part, by these findings.

3.
Phys Rev Lett ; 132(10): 102301, 2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38518341

RESUMEN

ATLAS measured the centrality dependence of the dijet yield using 165 nb^{-1} of p+Pb data collected at sqrt[s_{NN}]=8.16 TeV in 2016. The event centrality, which reflects the p+Pb impact parameter, is characterized by the total transverse energy registered in the Pb-going side of the forward calorimeter. The central-to-peripheral ratio of the scaled dijet yields, R_{CP}, is evaluated, and the results are presented as a function of variables that reflect the kinematics of the initial hard parton scattering process. The R_{CP} shows a scaling with the Bjorken x of the parton originating from the proton, x_{p}, while no such trend is observed as a function of x_{Pb}. This analysis provides unique input to understanding the role of small proton spatial configurations in p+Pb collisions by covering parton momentum fractions from the valence region down to x_{p}∼10^{-3} and x_{Pb}∼4×10^{-4}.

4.
Phys Rev Lett ; 132(8): 081801, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38457710

RESUMEN

Searches for new resonances are performed using an unsupervised anomaly-detection technique. Events with at least one electron or muon are selected from 140 fb^{-1} of pp collisions at sqrt[s]=13 TeV recorded by ATLAS at the Large Hadron Collider. The approach involves training an autoencoder on data, and subsequently defining anomalous regions based on the reconstruction loss of the decoder. Studies focus on nine invariant mass spectra that contain pairs of objects consisting of one light jet or b jet and either one lepton (e,µ), photon, or second light jet or b jet in the anomalous regions. No significant deviations from the background hypotheses are observed. Limits on contributions from generic Gaussian signals with various widths of the resonance mass are obtained for nine invariant masses in the anomalous regions.

5.
Phys Rev Lett ; 133(3): 031802, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39094132

RESUMEN

Statistical combinations of searches for charginos and neutralinos using various decay channels are performed using 139 fb^{-1} of pp collision data at sqrt[s]=13 TeV with the ATLAS detector at the Large Hadron Collider. Searches targeting pure-wino chargino pair production, pure-wino chargino-neutralino production, or Higgsino production decaying via standard model W, Z, or h bosons are combined to extend the mass reach to the produced supersymmetric particles by 30-100 GeV. The depth of the sensitivity of the original searches is also improved by the combinations, lowering the 95% C.L. cross-section upper limits by 15%-40%.

6.
Phys Rev Lett ; 132(23): 231801, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38905640

RESUMEN

A combination of searches for a new resonance decaying into a Higgs boson pair is presented, using up to 139 fb^{-1} of pp collision data at sqrt[s]=13 TeV recorded with the ATLAS detector at the LHC. The combination includes searches performed in three decay channels: bb[over ¯]bb[over ¯], bb[over ¯]τ^{+}τ^{-}, and bb[over ¯]γγ. No excess above the expected Standard Model background is observed and upper limits are set at the 95% confidence level on the production cross section of Higgs boson pairs originating from the decay of a narrow scalar resonance with mass in the range 251 GeV-5 TeV. The observed (expected) limits are in the range 0.96-600 fb (1.2-390 fb). The limits are interpreted in the type-I two-Higgs-doublet model and the minimal supersymmetric standard model, and constrain parameter space not previously excluded by other searches.

7.
Phys Rev Lett ; 132(20): 202301, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38829073

RESUMEN

Angular correlations between heavy quarks provide a unique probe of the quark-gluon plasma created in ultrarelativistic heavy-ion collisions. Results are presented of a measurement of the azimuthal angle correlations between muons originating from semileptonic decays of heavy quarks produced in 5.02 TeV Pb+Pb and pp collisions at the LHC. The muons are measured with transverse momenta and pseudorapidities satisfying p_{T}^{µ}>4 GeV and |η^{µ}|<2.4, respectively. The distributions of azimuthal angle separation Δϕ for muon pairs having pseudorapidity separation |Δη|>0.8, are measured in different Pb+Pb centrality intervals and compared to the same distribution measured in pp collisions at the same center-of-mass energy. Results are presented separately for muon pairs with opposite-sign charges, same-sign charges, and all pairs. A clear peak is observed in all Δϕ distributions at Δϕ∼π, consistent with the parent heavy-quark pairs being produced via hard-scattering processes. The widths of that peak, characterized using Cauchy-Lorentz fits to the Δϕ distributions, are found to not vary significantly as a function of Pb+Pb collision centrality and are similar for pp and Pb+Pb collisions. This observation will provide important constraints on theoretical descriptions of heavy-quark interactions with the quark-gluon plasma.

8.
Phys Rev Lett ; 132(2): 021802, 2024 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-38277610

RESUMEN

This Letter reports the observation of WZγ production and a measurement of its cross section using 140.1±1.2 fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. The WZγ production cross section, with both the W and Z bosons decaying leptonically, pp→WZγ→ℓ^{'}^{±}νℓ^{+}ℓ^{-}γ (ℓ^{(^{'})}=e, µ), is measured in a fiducial phase-space region defined such that the leptons and the photon have high transverse momentum and the photon is isolated. The cross section is found to be 2.01±0.30(stat)±0.16(syst) fb. The corresponding standard model predicted cross section calculated at next-to-leading order in perturbative quantum chromodynamics and at leading order in the electroweak coupling constant is 1.50±0.06 fb. The observed significance of the WZγ signal is 6.3σ, compared with an expected significance of 5.0σ.

9.
Phys Rev Lett ; 132(13): 131802, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38613283

RESUMEN

This Letter presents the first study of Higgs boson production in association with a vector boson (V=W or Z) in the fully hadronic qqbb final state using data recorded by the ATLAS detector at the LHC in proton-proton collisions at sqrt[s]=13 TeV and corresponding to an integrated luminosity of 137 fb^{-1}. The vector bosons and Higgs bosons are each reconstructed as large-radius jets and tagged using jet substructure techniques. Dedicated tagging algorithms exploiting b-tagging properties are used to identify jets consistent with Higgs bosons decaying into bb[over ¯]. Dominant backgrounds from multijet production are determined directly from the data, and a likelihood fit to the jet mass distribution of Higgs boson candidates is used to extract the number of signal events. The VH production cross section is measured inclusively and differentially in several ranges of Higgs boson transverse momentum: 250-450, 450-650, and greater than 650 GeV. The inclusive signal yield relative to the standard model expectation is observed to be µ=1.4_{-0.9}^{+1.0} and the corresponding cross section is 3.1±1.3(stat)_{-1.4}^{+1.8}(syst) pb.

10.
Value Health ; 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39094692

RESUMEN

OBJECTIVES: Quality-adjusted life years (QALYs) have been challenged as a measure of benefit for people with disabilities, particularly for those in low-utility health states or with irreversible disability. This study examined the impact of a QALY-based assessment on the price for a hypothetical treatment for Duchenne muscular dystrophy (DMD), a progressive, genetic neuromuscular disease. METHODS: A previously published, 5-state model, which analyzed treatments for early ambulatory (EA) DMD patients, was replicated, validated, and adapted to include early nonambulatory (ENA) DMD patients. The model was used to assess a QALY-based threshold price (maximum cost-effective price) for a hypothetical treatment for 13-year-old ENA and 5-year-old EA patients (initial health states with lower and higher utility, respectively). All inputs were replicated including willingness-to-pay thresholds of $50 000 to $200 000/QALY. RESULTS: In contrast to EA patients, ENA patients had a 98% modeled decline in QALY-based threshold price at a willingness-to-pay of $150 000/QALY or higher, despite equal treatment benefit (delayed progression/death). At $100 000/QALY or lower, net nontreatment costs exceeded health benefits, implying any treatment for ENA patients would not be considered cost-effective, even at $0 price, including an indefinite pause in disease progression. CONCLUSIONS: For certain severe, disabling conditions, traditional approaches are likely to conclude that treatments are not cost-effective at any price once a patient progresses to a disabled health state with low utility value. These findings elucidate theoretical/ethical concerns regarding potential discriminatory properties of traditional QALY assessments for people with disabilities, particularly those who have lost ambulation or have other physical limitations.

11.
Artículo en Inglés | MEDLINE | ID: mdl-39098578

RESUMEN

OBJECTIVE: To determine the extent and efficacy of attentional training as a form of neuropsychological rehabilitation to ameliorate attention deficits in adults with moderate-to-severe traumatic brain injury. DATA SOURCES: Articles published in Cumulative Index to Nursing and Allied Health Literature, Cochrane Library, PubMed, PsycINFO, Scopus, and Web of Science were searched between January 17, and February 27, 2021. STUDY SELECTION: Two reviewers blindly assessed studies for eligibility according to the following criteria: any article evaluating the efficacy of any type of behavioral intervention that targeted attention (by means of cognitive rehabilitative, psychoeducational, or neuropsychological strategies, at either an individual or group level) in adults who had sustained a formally documented moderate-to-severe traumatic brain injury. DATA EXTRACTION: Methodological quality of each article was blindly assessed by 2 reviewers. Data were extracted from each study, including study type, sample size, sample characteristics, summary of intervention, measures used to assess attention, statistical outcomes and results, effect size, conclusion, and limitations. DATA SYNTHESIS: 7314 articles were retrieved from databases, 4325 articles remained after duplicate removal, and finally 21 articles met eligibility criteria and were included in this review. Articles represented varied methodological quality in group or single subject design. Irrespective of the heterogeneity regarding intervention types and attentional outcome measures used across the studies, overall findings suggest that attentional gains can be made in this sample, irrespective of time since injury, age, and injury severity. Further, a growing interest in technology-based interventions is frequently used and holds promise to bettering rehabilitation efforts. However, there is still limited evidence supporting the ecological validity of attentional training interventions (eg, the transfer of treatment effects to daily activities). CONCLUSIONS: This article plays a crucial role in informing ongoing rehabilitation practices, guiding clinicians with evidence-based strategies and shaping future research directions for more effective attentional training guidelines.

12.
BMC Anesthesiol ; 24(1): 257, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39075354

RESUMEN

BACKGROUND: To enhance the utility of functional hemodynamic monitoring, the variables systolic slope (dP/dt) and dynamic arterial elastance (Eadyn) are calculated by the Hypotension Prediction Index (HPI) Acumen® Software. This study was designed to characterize the effects of phenylephrine and ephedrine on dP/dt and Eadyn. METHODS: This was a retrospective, non-randomized analysis of data collected during two clinical studies. All patients required intra-operative controlled mechanical ventilation and had an indwelling radial artery catheter connected to an Acumen IQ sensor. Raw arterial pressure waveform data was downloaded from the patient monitor and all hemodynamic measurements were calculated off-line. The anesthetic record was reviewed for bolus administrations of either phenylephrine or ephedrine. Cardiovascular variables prior to drug administration were compared to those following vasopressor administrations. The primary outcome was the difference for dP/dt and Eadyn at baseline compared with the average after the bolus administration. All data sets demonstrated non-normal distributions so statistical analysis of paired and unpaired data followed the Wilcoxon matched pairs signed-rank test or Mann-Whitney U test, respectively. RESULTS: 201 doses of phenylephrine and 100 doses of ephedrine were analyzed. All data sets are reported as median [95% CI]. Mean arterial pressure (MAP) increased from 62 [54,68] to 78 [76,80] mmHg following phenylephrine and from 59 [55,62] to 80 [77,83] mmHg following ephedrine. Stroke volume and cardiac output both increased. Stroke volume variation and pulse pressure variation decreased. Both drugs produced significant increases in dP/dt, from 571 [531, 645] to 767 [733, 811] mmHg/sec for phenylephrine and from 537 [509, 596] to 848 [779, 930] mmHg/sec for ephedrine. No significant changes in Eadyn were observed. CONCLUSION: Bolus administration of phenylephrine or ephedrine increases dP/dt but does not change Eadyn. dP/dt demonstrates potential for predicting the inotropic response to phenylephrine or ephedrine, providing guidance for the most efficacious vasopressor when treating hypotension. TRIAL REGISTRATION: Data was collected from two protocols. The first was deemed to not require written, informed consent by the Institutional Review Board (IRB). The second was IRB-approved (Effect of Diastolic Dysfunction on Dynamic Cardiac Monitors) and registered on ClinicalTrials.gov (NCT04177225).


Asunto(s)
Efedrina , Fenilefrina , Vasoconstrictores , Humanos , Estudios Retrospectivos , Fenilefrina/farmacología , Fenilefrina/administración & dosificación , Vasoconstrictores/administración & dosificación , Vasoconstrictores/farmacología , Efedrina/administración & dosificación , Efedrina/farmacología , Masculino , Femenino , Persona de Mediana Edad , Anciano , Hipotensión/tratamiento farmacológico
13.
Ethn Health ; : 1-19, 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39003724

RESUMEN

Despite the association of neighborhood quality with poorer adult health, limited research has explored the association between neighborhood disadvantage, e.g. Area Deprivation Index (ADI), and older Black adults' health, prospectively. This observational study examined the association between ADI and changes in longitudinal physical health within older Black adults. The analytic sample (n = 317) included data from waves 1 & 2 of the Baltimore Study of Black Aging: Patterns of Cognitive Aging (BSBA-PCA). Study variables included the Area Deprivation Index (ADI), objective (e.g. average heart rate) and subjective (e.g. activities of daily living) measures of physical health. Multiple linear regression models were conducted controlling for sociodemographic and social support characteristics. Participants living in more disadvantaged neighborhoods, based on national and state ADIs, were more likely to have a decreasing heart rate even after adjusting for covariates. Likewise, participants reporting increasing levels of ADL difficulty were living in a neighborhood with greater disadvantage based on national and state ADI rankings. Significant social support received and ADI (national and state) interactions were observed for average heart rate. The findings suggest that research on the effect of neighborhood quality and social support can enhance our understanding of its impact on older Black adults' health prospectively.

14.
Phys Rev Lett ; 131(15): 151802, 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37897746

RESUMEN

This Letter reports the observation of τ-lepton-pair production in ultraperipheral lead-lead collisions Pb+Pb→Pb(γγ→ττ)Pb and constraints on the τ-lepton anomalous magnetic moment a_{τ}. The dataset corresponds to an integrated luminosity of 1.44 nb^{-1} of LHC Pb+Pb collisions at sqrt[s_{NN}]=5.02 TeV recorded by the ATLAS experiment in 2018. Selected events contain one muon from a τ-lepton decay, an electron or charged-particle track(s) from the other τ-lepton decay, little additional central-detector activity, and no forward neutrons. The γγ→ττ process is observed in Pb+Pb collisions with a significance exceeding 5 standard deviations and a signal strength of µ_{ττ}=1.03_{-0.05}^{+0.06} assuming the standard model value for a_{τ}. To measure a_{τ}, a template fit to the muon transverse-momentum distribution from τ-lepton candidates is performed, using a dimuon (γγ→µµ) control sample to constrain systematic uncertainties. The observed 95% confidence-level interval for a_{τ} is -0.057

15.
Phys Rev Lett ; 131(15): 151902, 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37897770

RESUMEN

A search is made for potential ccc[over ¯]c[over ¯] tetraquarks decaying into a pair of charmonium states in the four muon final state using proton-proton collision data at sqrt[s]=13 TeV, corresponding to an integrated luminosity of 140 fb^{-1} recorded by the ATLAS experiment at LHC. Two decay channels, J/ψ+J/ψ→4µ and J/ψ+ψ(2S)→4µ, are studied. Backgrounds are estimated based on a hybrid approach involving Monte Carlo simulations and data-driven methods. Statistically significant excesses with respect to backgrounds dominated by the single parton scattering are seen in the di-J/ψ channel consistent with a narrow resonance at 6.9 GeV and a broader structure at lower mass. A statistically significant excess is also seen in the J/ψ+ψ(2S) channel. The fitted masses and decay widths of the structures are reported.

16.
Phys Rev Lett ; 131(16): 162301, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37925689

RESUMEN

A key open question in the study of multiparticle production in high-energy pp collisions is the relationship between the "ridge"-i.e., the observed azimuthal correlations between particles in the underlying event that extend over all rapidities-and hard or semihard scattering processes. In particular, it is not known whether jets or their soft fragments are correlated with particles in the underlying event. To address this question, two-particle correlations are measured in pp collisions at sqrt[s]=13 TeV using data collected by the ATLAS experiment at the LHC, with an integrated luminosity of 15.8 pb^{-1}, in two different configurations. In the first case, charged particles associated with jets are excluded from the correlation analysis, while in the second case, correlations are measured between particles within jets and charged particles from the underlying event. Second-order flow coefficients, v_{2}, are presented as a function of event multiplicity and transverse momentum. These measurements show that excluding particles associated with jets does not affect the measured correlations. Moreover, particles associated with jets do not exhibit any significant azimuthal correlations with the underlying event, ruling out hard processes contributing to the ridge.

17.
Phys Rev Lett ; 131(7): 072301, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37656838

RESUMEN

Jet quenching is the process of color-charged partons losing energy via interactions with quark-gluon plasma droplets created in heavy-ion collisions. The collective expansion of such droplets is well described by viscous hydrodynamics. Similar evidence of collectivity is consistently observed in smaller collision systems, including pp and p+Pb collisions. In contrast, while jet quenching is observed in Pb+Pb collisions, no evidence has been found in these small systems to date, raising fundamental questions about the nature of the system created in these collisions. The ATLAS experiment at the Large Hadron Collider has measured the yield of charged hadrons correlated with reconstructed jets in 0.36 nb^{-1} of p+Pb and 3.6 pb^{-1} of pp collisions at 5.02 TeV. The yields of charged hadrons with p_{T}^{ch}>0.5 GeV near and opposite in azimuth to jets with p_{T}^{jet}>30 or 60 GeV, and the ratios of these yields between p+Pb and pp collisions, I_{pPb}, are reported. The collision centrality of p+Pb events is categorized by the energy deposited by forward neutrons from the struck nucleus. The I_{pPb} values are consistent with unity within a few percent for hadrons with p_{T}^{ch}>4 GeV at all centralities. These data provide new, strong constraints that preclude almost any parton energy loss in central p+Pb collisions.

18.
Phys Rev Lett ; 131(17): 172301, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37955510

RESUMEN

This letter presents a measurement of the nuclear modification factor of large-radius jets in sqrt[s_{NN}]=5.02 TeV Pb+Pb collisions by the ATLAS experiment. The measurement is performed using 1.72 nb^{-1} and 257 pb^{-1} of Pb+Pb and pp data, respectively. The large-radius jets are reconstructed with the anti-k_{t} algorithm using a radius parameter of R=1.0, by reclustering anti-k_{t} R=0.2 jets, and are measured over the transverse momentum (p_{T}) kinematic range of 158

19.
Phys Rev Lett ; 131(18): 181901, 2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37977601

RESUMEN

This Letter reports the observation of single top quarks produced together with a photon, which directly probes the electroweak coupling of the top quark. The analysis uses 139 fb^{-1} of 13 TeV proton-proton collision data collected with the ATLAS detector at the Large Hadron Collider. Requiring a photon with transverse momentum larger than 20 GeV and within the detector acceptance, the fiducial cross section is measured to be 688±23(stat) _{-71}^{+75}(syst) fb, to be compared with the standard model prediction of 515_{-42}^{+36} fb at next-to-leading order in QCD.

20.
Phys Rev Lett ; 131(6): 061803, 2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37625051

RESUMEN

A search for a long-lived, heavy neutral lepton (N) in 139 fb^{-1} of sqrt[s]=13 TeV pp collision data collected by the ATLAS detector at the Large Hadron Collider is reported. The N is produced via W→Nµ or W→Ne and decays into two charged leptons and a neutrino, forming a displaced vertex. The N mass is used to discriminate between signal and background. No signal is observed, and limits are set on the squared mixing parameters of the N with the left-handed neutrino states for the N mass range 3 GeV

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