KinomeMETA: meta-learning enhanced kinome-wide polypharmacology profiling

Kinase inhibitors are crucial in cancer treatment, but drug resistance and side effects hinder the development of effective drugs. To address these challenges, it is essential to analyze the polypharmacology of kinase inhibitor and identify compound with high selectivity profile. This study presents KinomeMETA, a framework for profiling the activity of small molecule kinase inhibitors across a panel of 661 kinases. By training a meta-learner based on a graph neural network and fine-tuning it to create kinase-specific learners, KinomeMETA outperforms benchmark multi-task models and other kinase profiling models. It provides higher accuracy for understudied kinases with limited known data and broader coverage of kinase types, including important mutant kinases. Case studies on the discovery of new scaffold inhibitors for membrane-associated tyrosine- and threonine-specific cdc2-inhibitory kinase and selective inhibitors for fibroblast growth factor receptors demonstrate the role of KinomeMETA in virtual screening and kinome-wide activity profiling. Overall, KinomeMETA has the potential to accelerate kinase drug discovery by more effectively exploring the kinase polypharmacology landscape.

Hyperon Polarization along the Beam Direction Relative to the Second and Third Harmonic Event Planes in Isobar Collisions at sqrt[s_{NN}]=200 GeV

The polarization of Λ and Λ[over ¯] hyperons along the beam direction has been measured relative to the second and third harmonic event planes in isobar Ru+Ru and Zr+Zr collisions at sqrt[s_{NN}]=200  GeV. This is the first experimental evidence of the hyperon polarization by the triangular flow originating from the initial density fluctuations. The amplitudes of the sine modulation for the second and third harmonic results are comparable in magnitude, increase from central to peripheral collisions, and show a mild p_{T} dependence. The azimuthal angle dependence of the polarization follows the vorticity pattern expected due to elliptic and triangular anisotropic flow, and qualitatively disagrees with most hydrodynamic model calculations based on thermal vorticity and shear induced contributions. The model results based on one of existing implementations of the shear contribution lead to a correct azimuthal angle dependence, but predict centrality and p_{T} dependence that still disagree with experimental measurements. Thus, our results provide stringent constraints on the thermal vorticity and shear-induced contributions to hyperon polarization. Comparison to previous measurements at RHIC and the LHC for the second-order harmonic results shows little dependence on the collision system size and collision energy.

Measurements of Groomed-Jet Substructure of Charm Jets Tagged by D^{0} Mesons in Proton-Proton Collisions at sqrt[s]=13 TeV

Understanding the role of parton mass and Casimir color factors in the quantum chromodynamics parton shower represents an important step in characterizing the emission properties of heavy quarks. Recent experimental advances in jet substructure techniques have provided the opportunity to isolate and characterize gluon emissions from heavy quarks. In this Letter, the first direct experimental constraint on the charm-quark splitting function is presented, obtained via the measurement of the groomed shared momentum fraction of the first splitting in charm jets, tagged by a reconstructed D^{0} meson. The measurement is made in proton-proton collisions at sqrt[s]=13  TeV, in the low jet transverse-momentum interval of 15≤p_{T}^{jet ch}<30  GeV/c where the emission properties are sensitive to parton mass effects. In addition, the opening angle of the first perturbative emission of the charm quark, as well as the number of perturbative emissions it undergoes, is reported. Comparisons to measurements of an inclusive-jet sample show a steeper splitting function for charm quarks compared with gluons and light quarks. Charm quarks also undergo fewer perturbative emissions in the parton shower, with a reduced probability of large-angle emissions.

[Research progress on biomarkers and detection methods for Alzheimer's disease diagnosis in vitro]

Alzheimer's disease (AD) is a neurodegenerative disease with insidious onset, posing a serious threat to human physical and mental health. The cognitive impairments caused by AD are generally diffuse and overlap symptomatically with other neurodegenerative diseases. Moreover, the symptoms of AD are often covert, leading to missed opportunities for optimal treatment after diagnosis. Therefore, early diagnosis of AD is crucial. In vitro diagnostic biomarkers not only contribute to the early clinical diagnosis of AD but also aid in further understanding the disease's pathogenesis, predicting disease progression, and observing the effects of novel candidate therapeutic drugs in clinical trials. Currently, although there are numerous biomarkers associated with AD diagnosis, the complex nature of AD pathogenesis, limitations of individual biomarkers, and constraints of clinical detection methods have hindered the development of efficient, cost-effective, and convenient diagnostic methods and standards. This article provides an overview of the research progress on in vitro diagnostic biomarkers and detection methods related to AD in recent years.

Observation of Single-Top-Quark Production in Association with a Photon Using the ATLAS Detector

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.

The jigsaw puzzle of pedigree: whole-genome resequencing reveals genetic diversity and ancestral lineage in Sunong black pigs

The Sunong black pig is a new composite breed under development generated from Chinese indigenous pig breeds (i.e., Taihu and Huai) and intensive pig breeds (i.e., Landrace and Berkshire), which is an important genetic material for studying breeding mechanisms. However, there is currently limited knowledge about the genetic structure and germplasm characteristics of Sunong black pigs. To comprehensively understand their genetic composition and ancestry proportions, we performed population structure and local ancestry inference analysis based on whole-genome sequencing information. The results showed that Sunong black pigs could be clustered independently into a group, whose pedigree was intermediate between indigenous and commercial pig breeds, but closer to commercial pigs. Furthermore, local ancestry inference analysis revealed that Sunong black pigs inherited immune and reproductive traits from indigenous pig breeds, including CC and CXC chemokine family, Toll-like receptor family, IFN gene family, ESR1, AREG and EREG gene, while growth and development-related traits were inherited from commercial pig breeds, including IGF1 and GSY2 gene. Overall, Sunong black pigs have formed a relatively stable genome structure with some advantageous traits inherited from their ancestral breeds. This study deepened the understanding of the breeding mechanism of Sunong black pigs and provided a reference for cross-breeding programmes in livestock.

Measurement of Suppression of Large-Radius Jets and Its Dependence on Substructure in Pb+Pb Collisions at sqrt[s_{NN}]=5.02 TeV with the ATLAS Detector

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 Collapse

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Measurement of the Sensitivity of Two-Particle Correlations in pp Collisions to the Presence of Hard Scatterings

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.

[Effects of the anterolateral thigh chimeric perforator flaps in repairing complex wounds of foot and ankle]

Objective: To investigate the effects of anterolateral thigh chimeric perforator flap in repairing complex wounds of foot and ankle. Methods: A retrospective observational study was conducted. From May 2018 to June 2022, 23 patients who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University to repair complex wounds of foot and ankle with anterolateral thigh chimeric perforator flaps, including 15 males and 8 females, aged from 20 to 66 years. The wounds were all accompanied by bone exposure and defects, and were complicated with varying degrees of infection. All patients underwent debridement and continuous vacuum sealing drainage treatment for 1 week in stage Ⅰ, with the skin and soft tissue defect area after debridement being 10 cm×5 cm to 22 cm×7 cm. In stage Ⅱ, the anterolateral thigh chimeric perforator flap was used to cover the defective wound, of which the muscle flap was used to fill the deep invalid cavity of the ankle joint or cover bone and internal fixation exposures, and the skin flap was used to cover the superficial wound, with the area of the skin flap ranging from 11 cm×6 cm to 23 cm×8 cm, and the area of the muscle flap ranging from 4.0 cm×2.5 cm to 8.0 cm×5.0 cm. The survival of the flap was observed after operation. During follow-up, the color, texture, appearance, and complications of the flap were observed, the function of ankle joint and its range of dorsiflexion motion and plantar flexion motion were measured, and the scar hyperplasia and muscular hernia in donor area were observed. Results: Ecchymosis and epidermal necrosis occurred at the tip of the flap in 1 patient on 5 days after operation and healed after dressing change for 1 week; the other flaps of patients survived successfully. After 6 to 40 months of follow-up, the color, texture, and shape of flaps were good, but 1 patient was not satisfied with the shape of the flap because of flap swelling; the ankle joint movement was basically normal, the dorsiflexion motion was 15-30°, and the plantar flexion motion was 20-45°; the scar hyperplasia in the donor area of the flap was not obvious, and no muscular hernia occurred. Conclusions: The anterolateral thigh chimeric perforator flap can effectively fill the deep invalid cavity of ankle joint and cover the superficial wound at the same time, with minimal damage to the donor site. So it is an ideal flap for repairing the complex wounds of foot and ankle.

Temporal Structures in Positron Spectra and Charge-Sign Effects in Galactic Cosmic Rays

We present the precision measurements of 11 years of daily cosmic positron fluxes in the rigidity range from 1.00 to 41.9 GV based on 3.4×10^{6} positrons collected with the Alpha Magnetic Spectrometer (AMS) aboard the International Space Station. The positron fluxes show distinctly different time variations from the electron fluxes at short and long timescales. A hysteresis between the electron fluxes and the positron fluxes is observed with a significance greater than 5σ at rigidities below 8.5 GV. On the contrary, the positron fluxes and the proton fluxes show similar time variation. Remarkably, we found that positron fluxes are modulated more than proton fluxes with a significance greater than 5σ for rigidities below 7 GV. These continuous daily positron fluxes, together with AMS daily electron, proton, and helium fluxes over an 11-year solar cycle, provide unique input to the understanding of both the charge-sign and mass dependencies of cosmic rays in the heliosphere.

Observation of an Excess of Dicharmonium Events in the Four-Muon Final State with the ATLAS Detector

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.

Observation of the γγ→ττ Process in Pb+Pb Collisions and Constraints on the τ-Lepton Anomalous Magnetic Moment with the ATLAS Detector

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 Collapse

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[Bioinformatics analysis of the RNA binding protein DDX39 of Toxoplasma gondii]

OBJECTIVE

To analyze the RNA binding protein of Toxoplasma gondii (TgDDX39) using bioinformatics technology, and to evaluate the immunogenicity of TgDDX39, so as to provide insights into development of toxoplasmosis vaccines.

METHODS

The amino acid sequences of TgDDX39 were retrieved from the ToxoDB database, and the physicochemical properties, transmembrane structure domain, signal peptide sites, post-translational modification sites, coils, secondary and tertiary structures, hydrophobicity, and antigenic epitopes of the TgDDX39 protein were predicted using online bioinformatics tools, incluiding ProtParam, TMHMM 2.0, SignalP 5.0, NetPhos 3.1, COILS, SOPMA, Phyre2, ProtScale, ABCpred, SYFPEITHI and DNA-STAR.

RESULTS

TgDDX39 protein was predicted to be an unstable hydrophilic protein with the molecular formula of C2173H3458N598O661S18, which contained 434 amino acids and had an estimated molecular weight of 49.1 kDa and a theoretical isoelectric point of 5.55. The protein was predicted to have an extremely low possibility of signal peptides, without transmembrane regions, and contain 27 phosphorylation sites. The β turn and random coils accounted for 39.63% of the secondary structure of the TgDDX39 protein, and a coiled helix tended to produce in one site. In addition, the TgDDX39 protein contained multiple B and T cell antigenic epitopes.

CONCLUSIONS

Bioinformatics analyses predict that TgDDX39 protein has high immunogenicity and contains multiple antigenic epitopes. TgDDX39 protein is a potential candidate antigen for vaccine development.

Locoregional Control Benefit of a Tumor Bed Boost for Ductal Carcinoma In Situ (DCIS)

PURPOSE/OBJECTIVE(S)

Radiotherapy (RT) following breast conserving surgery (BCS) for ductal carcinoma in situ (DCIS) reduces invasive and in situ recurrences. Whereas landmark studies suggest that a tumor bed boost improves local control for invasive breast cancer, the benefit in DCIS remains less certain. We evaluated outcomes of DCIS patients treated with or without a boost and hypothesized that a tumor bed boost would improve locoregional control rates.

MATERIALS/METHODS

The study cohort comprised patients with DCIS who underwent BCS at our institution from 2004-2018. Clinicopathologic features, treatment parameters and outcomes were ascertained from medical records. Patient and tumor characteristics were evaluated relative to outcomes using univariable and multivariable Cox models. Recurrence-free survival (RFS) estimates were generated using the Kaplan Meier method.

RESULTS

We identified 1675 patients who underwent BCS for DCIS (median age 56 [interquartile range (IQR) 49, 64]). Boost RT was employed in 68% of cases (n = 1146) and endocrine therapy in 32% (n = 536). At a median follow-up of 4.2 years (IQR 1.4, 7.0), we observed 61 locoregional recurrence events (56 local, 5 regional) and 21 deaths. Univariable logistic regression demonstrated that boost RT was more common among younger patients (p<0.001) with positive/close margins (p<0.001), and with larger tumors (p<0.001) of higher grade (p = 0.025). The 10-year RFS rate was 88.8% among those receiving a boost and 84.3% among those without a boost (p = 0.3), and neither univariable nor multivariable analyses revealed an association between boost RT and locoregional recurrence.

CONCLUSION

Among patients with DCIS who underwent BCS, use of a tumor bed boost was not associated with locoregional recurrence or RFS. Despite a preponderance of adverse features among the boost cohort, outcomes were similar to those not receiving a boost, suggesting that a boost may mitigate risk of recurrence among patients with high-risk features. Ongoing studies will elucidate the extent to which a tumor bed boost influences disease control rates.

Dosimetric Predictors of Acute Diarrhea in Locally Advanced Rectal Cancer Patients Treated with Neoadjuvant Chemoradiation with Capecitabine and Irinotecan: A Discovery and Validation Study

PURPOSE/OBJECTIVE(S)

Additional irinotecan can increase the pCR rate from 15% to 30% compared with capecitabine-based neoadjuvant chemoradiotherapy in locally advanced rectal cancer, while more acute diarrhea was induced and predictors of diarrhea have yet to be fully elucidated. In this analysis, we report the incidence of and factors associated with grade 3+ acute diarrhea in LARC patients treated with the CaplriRT regimen in the CinClare trial.

MATERIALS/METHODS

We identified the dosimetric markers with a lasso-Cox risk scoring model tested on CaplriRT group patients in the CinClare trial at our institution from 2015 to 2017 (CinClare, NCT02605265), and then independently validated according to a predefined protocol in patients treated with neoadjuvant chemoradiation with capecitabine and irinotecan from 2019 to 2022 (NCT05688033). Clinical documentation and patient-reported outcomes were reviewed to determine grade 3+ acute diarrhea events.

RESULTS

A total of 116 patients from Cinclare trial treated with CaplriRT regimen were used as a training cohort to obtain dosimetric prediction model and 168 patients were used for independent validation. The majority received 50 Gray (Gy) in 25 fractions with concurrent capecitabine and irinotecan. Median number of concurrent chemotherapy cycles received was 4 (IQR: 3-4). Seventeen (23.6%) patients treated with the CaplriRT regimen in the CinClare trial experienced grade 3+ acute diarrhea. Dosimetric predictors of acute diarrhea included peritoneal space volume receiving 25 Gy or greater (V25Gy). The single multivariate Cox regression, and receiver operating characteristic (ROC) curve analysis showed that the model had good predictive ability (p<0.05). It was also validated using the validation cohort. Patients with peritoneal space V25Gy>950 cm3 were associated with a higher risk of 3+ acute diarrhea compared with those without constraints of V25Gy (p = 0.002).

CONCLUSION

Peritoneal space V25Gy as an important predictor of acute diarrhea during capecitabine and irinotecan neoadjuvant chemoradiation treatment. Peritoneal space V25Gy < 950 cm3 may reduce acute diarrhea toxicity.

Standard Therapy vs. Individualized Therapy in Elderly Locally Advanced Nasopharyngeal Carcinoma: A Real-World Study

PURPOSE/OBJECTIVE(S)

Concurrent chemoradiotherapy (CRT) with/without induction chemotherapy has been the standard therapy (ST) for locally advanced nasopharyngeal carcinoma (LA-NPC). However, most patients supporting these clinical trials were younger than 65 years of age. For the toxicity of CRT and the poor tolerance of elderly patients, it is still controversial whether ST could bring the most promising survival benefits for elderly NPC compared with individualized therapy (IT). Thus, in this real-world study we compared the survival and safety of ST with IT in elderly LA-NPC to explore an effective and tolerable treatment strategy for elderly LA-NPC.

MATERIALS/METHODS

A total of 109 newly diagnosed elderly LA-NPC (>65 years old) from Jan. 2013-Jul. 2020 were retrospectively enrolled and divided into the ST group and IT group according to the original treatment tendency. ST refers to CRT with/without induction chemotherapy. IT group included patients not suitable for CRT and were given individualized treatment fully discussed by at least two oncologists from our head and neck team. A 1:1 propensity score matching (PSM) generated a matched cohort of ST and IT. The survivals and treatment related toxicities were compared between the two groups.

RESULTS

There were 46 cases in the ST group and 63 cases in the IT group. The 5-year overall survival (OS) rate, cancer-specific survival (CSS) rate, progression- free survival (PFS) rate, local recurrence-free survival (LRFS) rate and distant metastasis-free survival (DMFS) rate were 68.64%, 76.42%, 73.69%, 85.67% and 86.82%, respectively. By 1:1PSM, 35 cases in each group were matched. No significant differences of OS, CSS, PFS, LRFS and DMFS were found between ST and IT groups in the PSM-matched cohorts (P = 0.87, P = 0.79, P = 0.51, P = 0.81 and P = 0.24, respectively). Compared with patients in the ST group, cases received IT were associated with less severe acute toxicities including anemia, leucopenia, neutropenia, and thrombocytopenia.

CONCLUSION

For elderly LA-NPC, IT had similar survivals while less severe toxicities compared with ST, which revolutionarily challenged the role of ST for elderly LA-NPC. In the future, more studies are need to explore a less toxic treatment modality with noninferior efficacy for elderly LA-NPC.

Carbon Ion Radiotherapy Exerts Anti-Tumor Activity by Inducing cGAS-STING Activation and Immune Response in Prostate Cancer-Bearing Mice

PURPOSE/OBJECTIVE(S)

The aim of this study was to assess the influence on immune cell infiltration and T cell effector function to explore the immune response evoked by carbon ion radiotherapy (CiRT) in prostate cancer-bearing mice, and explored the mechanisms underlying CiRT-induced anti-tumor efficacy, involved in cGAS-STING signaling pathway.

MATERIALS/METHODS

C57BL/6 and BALB/c nude mouse tumor models were used to evaluate the efficacy of CiRT on tumor growth. Activation of cGAS-STING signaling pathway was performed by immunofluorescence analysis of cytoplasmic double-stranded DNA, western blot analysis of key factors involved in cGAS-STING pathway, and qRT-PCR analysis of the key downstream molecules like CCL5, CXCL10 and IFNβ1. Investigation of alterations of immunophenotypes including the quantification, memory status, exhaustion marker expression, and effector function were assessed by flow cytometry.

RESULTS

CiRT showed more powerful tumor growth control of immunocompetent syngeneic C57BL/6 mice than photon radiotherapy did at biological equivalent dose of 5Gy. CiRT induces cytoplasmic DNA and cGAS-STING activation, and is functionally responsible for the observed tumor growth suppression. CiRT exerts anti-tumor effect by triggering immune response, characterized by increased infiltration of CD4+ T cells and macrophages in tumor, enhanced frequencies of CD8+ T cells and CD8+ T effector memory cells in spleen, improved interferon (IFN)-γ production ability of CD8+ tumor-infiltrating lymphocyte cells, and reduced expression of exhausted T cells in tumor and spleen.

CONCLUSION

Our findings indicate that CIRT exerts excellent anti-tumor activity, which may be attributed to the induction of cGAS-STING activation and immune response, manifested by increased immune cell infiltration, improved T cell effector function and enhanced immune memory.

Long-Term Anorectal Function in Rectal Cancer Patients Managed by a Watch-and-Wait Strategy after Neoadjuvant Therapy: A Cross-Sectional Study

PURPOSE/OBJECTIVE(S)

Rectal cancer patients reaching complete clinical response (cCR) after neoadjuvant chemoradiotherapy can be offered a nonoperative watch-and-wait (W&W) strategy. As evidence of good oncological outcomes accumulates, the functional outcomes remain less explored. The aim of this study is to comprehensively assess the long-term rectal toxicity and anorectal function in patients managed by a W&W strategy and to investigate the clinical risk factors for anorectal dysfunction.

MATERIALS/METHODS

Seventy W&W patients who were disease-free at the moment of recruitment were included. A minimum 2-year follow-up was considered. We graded late rectal toxicity according to the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer (RTOG/EORTC) scale and the Late Effects of Normal Tissue/Subjective Objective Management Analytic (LENT/SOMA) system. Long-term anorectal function was assessed with the Wexner score, the Low Anterior Resection Syndrome score (LARS score), and the Memorial Sloan Kettering Bowel Function Instrument (MSK BFI).

RESULTS

All patients received standard chemoradiotherapy consisting of a total dose of 5000 cGy in 25 fractions. The median tumor distance from the anal verge was 3 (IQR 2-4) cm. After a median follow-up of 43 (IQR 28-66) months, less than half of patients developed Grade 1 (40.0%) or Grade 2 (1.4%) late rectal toxicity, and no patients complained of higher grades. LENT/SOMA criteria also identified more patients with mild symptoms. The most frequent symptoms were sphincter control problems, mainly manifested as fecal urgency, reported by 60.0% of patients. For long-term anorectal function, the median LARS score was 16 (IQR 4-25). 17.1% of patients reported minor LARS and 15.7% reported major LARS. The median Wexner score was 2 (IQR 0-3). The median MSK BFI total score was 82 (IQR 77-86). Smoking history was an independent risk factor for anorectal dysfunction in multivariate analyses (OR = 6.491, 95% CI 1.536-27.432).

CONCLUSION

Rectal cancer patients managed by a watch-and-wait strategy after neoadjuvant chemoradiotherapy have retained satisfactory anorectal function. However, fecal urgency might be a common problem. Smoking history was an independent risk factor for long-term anorectal dysfunction. Prospective studies with emphasis on bowel function outcomes containing a larger number of patients are needed.

Clinical Outcomes of Image-Guided Volumetric Modulated Arc Therapy for Total Body Irradiation

PURPOSE/OBJECTIVE(S)

Volumetric modulated arc therapy (VMAT)-based total body irradiation (TBI) with image guidance is a novel technique that is increasing in implementation. Compared to conventional TBI, VMAT-TBI offers favorable dose homogeneity, better organ-at-risk sparing, and enhanced patient comfort. However, whether these dosimetric advantages translate to improved clinical outcomes that justify the increased planning and delivery burden is not well understood. Only a single study of clinical outcomes of VMAT-TBI exists in the literature. We present the largest study to date of clinical outcomes of VMAT-TBI.

MATERIALS/METHODS

In this IRB-approved retrospective single-institution study, all patients treated with VMAT-TBI conditioning for allogeneic stem cell transplant, per the institution's published protocol, were identified. Dosimetric data were abstracted from the radiation oncology treatment planning system. Clinical data were abstracted from the electronic medical record. The primary outcome was six-month overall survival (6M OS) from the last day of TBI by Kaplan-Meier method.

RESULTS

Fifty-five patients (47 adult and 8 pediatric) were treated with VMAT-TBI between June 2020 and December 2022. All patients received conditioning chemotherapy with standard-dose TBI of 12 or 13.2 Gy in 8 twice-daily fractions. The PTV coverage (V95%) mean was 95.3% ± 1.2%. Mean lung dose was 9.5 Gy ± 0.6 for adult patients and 8.4 Gy ± 0.9 for pediatric patients. Mean lung dose rate was 18.0 cGy/min ± 4.4. Mean kidney dose was 5.9 Gy ± 0.6. Mean skin dose measured by MOSFET was 12.7 Gy ± 1.2. Median treatment time was 63 minutes (range: 53-104). Median follow-up was 7.7 months. At most recent follow-up, 78% of patients were alive. 6M OS was 82%. Common acute toxicities were fatigue (90.9% of patients, all grade 1-2), diarrhea (70.9%, all grade 1-2), nausea (76.4%, all grade 1-2), mucositis (60% grade 1-2, 12.7% grade 3, 1.8% grade 4, no grade 5), and xerostomia (54.5%, all grade 1). Mean pretreatment FEV1 was 98.3 percent of predicted (%p) ± 11.9%p and mean posttreatment FEV1 was 94.7%p ± 13.8%p. Mean pretreatment GFR was 101.4mL/min/1.73m² ± 17.4, mean 3-month posttreatment GFR was 92.4 ± 20.0, and mean 6-month posttreatment GFR was 97.5 ± 26.48. One patient experienced grade 2 pneumonitis; there were no other cases of pneumonitis. There were no acute grade 3+ toxicities aside from mucositis. Observed late toxicities were cataracts (7.3%, all grades 1-3) and hypothyroidism (12.7%, all grades 1-2). There were no grade 3+ late toxicities. Mild acute graft-versus-host disease (GVHD) was noted in 27.2% of patients and mild chronic GVHD was noted in 14.5% of patients, with no other cases of GVHD.

CONCLUSION

In the largest series to date, VMAT-TBI had excellent oncologic and toxicity outcomes. A randomized trial of VMAT-TBI versus standard TBI is warranted.

The Incidence and Prognosis Value of Perineural Invasion in Rectal Carcinoma: From Meta-Analyses and Real-World Clinical Pathological Features

AIMS

Perineural invasion (PNI) is a special type of metastasis of several cancers and has been reported as being a factor for poor prognosis in colorectal carcinoma. However, investigations of PNI in only rectal cancer and a comprehensive analysis combining meta-analyses with real-world case studies remain lacking.

MATERIALS AND METHODS

First, articles from 2000 to 2020 concerning the relationship between PNI and rectal cancer prognoses and clinical features were meta-analysed. Subsequently, we carried out a retrospective analysis of 312 rectal cancer cases that underwent radical surgery in the real world. The incidence of PNI and the relationship between PNI and prognosis, as well as clinicopathological factors, were investigated.

RESULTS

The incidence of PNI was 23.09% and 33.01% in the meta-analysis and clinical cases, respectively. PNI occurred as early as stage I (2.94%). Moreover, neoadjuvant therapy significantly reduced the PNI-positive rate (20.34% versus 26.54%). Both meta-analysis and real-world clinical case studies suggested that PNI-positive patients had poorer prognoses than PNI-negative patients. We established an effective risk model consisting of T stage, differentiation and lymphovascular invasion to predict PNI in rectal cancer.

CONCLUSION

PNI is a poor prognostic factor for rectal cancer and could occur even in stage I. Additionally, neoadjuvant therapy could sufficiently reduce the PNI-positive rate. T stage, lymphovascular invasion and differentiation grade were independent risk factors for PNI and the risk model that included these factors could predict the probability of PNI.

Focused Ultrasound for Blood-Brain Barrier Opening and Delivery of Anti-PD1 in Diffuse Midline Gliomas

PURPOSE/OBJECTIVE(S)

Diffuse midline glioma with H3K27 mutation is a fatal pediatric brain tumor, most commonly arising in the brainstem. This tumor remains universally fatal, despite a multitude of clinical trials, with a median overall survival of only 9-12 months. While immune-checkpoint inhibitors (ICIs) have transformed the treatment landscape of multiple solid tumors, delivery past the blood brain barrier (BBB) remains challenging. Programmed cell death protein 1 (PD1) is an immune checkpoint protein expressed on the surface of activated T cells; interaction with its ligand, PDL1, is tumor-protective, dampening T cell response. Recent phase I clinical trials have shown that ICIs targeting proteins along the PD1/PDL1 axis are well tolerated in patients with DMG; however, efficacy remains low. The blood-brain barrier (BBB) poses a major challenge to the efficacious delivery of therapeutic agents with large molecular size, such as anti-PD1. We hypothesize that BBB opening (BBBO) using focused ultrasound (FUS), a form of non-ionizing acoustic radiation, can enhance delivery and efficacy of anti-PD1 for treatment of DMG.

MATERIALS/METHODS

We established a syngeneic mouse DMG model with intracranial injection of cell line 4423 (PDGFB+, H3.3K27M, p53-/-). Magnetic resonance imaging (MRI) was utilized to evaluate BBBO and tumor progression. We measured delivery of anti-PD1 after BBBO using Western Blot and 3D in vivo optical fluorescent imaging/CT (OI/CT) of Cy7 labeled anti-PD1.

RESULTS

We demonstrate that delivery of anti-PD1 can be enhanced over 3.5-fold after reversible BBBO with FUS and concurrent microbubble administration. OI/CT revealed enhanced real-time antibody distribution peritumorally. Furthermore, we demonstrate that combined treatment of FUS and anti-PD1 led to benefit in local control of tumor growth using volumetric analysis of MRI. Preliminary survival studies suggest a positive trend for overall survival.

CONCLUSION

Our results support that FUS-mediated BBBO can increase treatment efficacy of anti-PD1 in a DMG murine model, due to improved targeted delivery to the tumoral region after systemic antibody administration. We consider these findings strong rationale for further investigation of the therapeutic effects of combinatorial treatment using FUS-mediated BBBO and ICIs for the treatment of DMG.

The Presence of Extensive Lymphovascular Invasion (LVI) is Associated with Higher Risk of Recurrence in Curatively Treated Breast Cancer Patients

PURPOSE/OBJECTIVE(S)

Lymphovascular invasion (LVI) is a pathological feature seen in breast cancer that may be an important step in cancer metastasis. Multiple datasets have demonstrated a correlation between LVI and local-regional recurrence (LRR). Whether the extent of LVI is an incremental determinant of LRR risk is unknown. We describe clinical outcomes in women with invasive breast cancer stratified by: 1) absence of LVI (neg), 2) LVI focal or suspicious (FS-LVI), 3) usual (non-extensive) LVI (LVI) and 4) extensive LVI (E-LVI).

MATERIALS/METHODS

Between December 2009 and August 2021, there were 8,837 patients with early-stage breast cancer (T1-2 and N0-2a) were treated with curative intent and were evaluable. Clinical-pathological details were abstracted by retrospective review. The description of LVI was abstracted from pathology reports. Recurrence and survival outcomes were compared based on the extent of LVI.

RESULTS

Of the 8837 patients studied, 5584 were neg, 461 had FS-LVI, 2315 had LVI, and 477 had E-LVI. The E-LVI cohort had baseline characteristics suggestive of higher risk such as younger median age, higher proportion of grade 3, more nodal positivity, more mastectomy (67% vs 48%), and higher use of chemotherapy compared to LVI. The cumulative incidence of LRR and DM was highest in the E-LVI group. Using LVI as the reference, the presence of E-LVI, age, tumor size, ER status, grade, mastectomy, and close/positive margins were independent variables for LRR on Cox multivariable regression (Table 1). To assess the effect with an alternate statistical method, we created propensity matched cohorts (matched for age, size, receptors, grade, surgery type, margins and chemotherapy/RT use); a statistical difference in OS was noted between groups with LVI vs E-LVI (HR 1.44 (CI 1.06-1.96, p = 0.018), but not in LRR (HR 1.31 (CI 0.87-1.97, p = 0.2) or DM (HR 1.16 (CI 0.88-1.53, p = 0.3).

CONCLUSION

Our work suggests that patients with E-LVI are at a higher risk for LRR compared to patients with usual LVI, despite maximal standard of care treatment. This is important because E-LVI can be determined from breast specimens, and may help define indications for RNI/PMRT when nodal information is not available.

AI-Derived CT Body Composition in Advanced Non-Small Cell Lung Cancer: A Multicohort Study

PURPOSE/OBJECTIVE(S)

The relationship between body composition (BC) and cancer outcomes is complex and incompletely understood. Previous research in non-small cell lung cancer (NSCLC) has been limited to small single-institution studies, which have yielded inconsistent results.

MATERIALS/METHODS

We conducted a comprehensive multicohort analysis to evaluate the impact of BC on overall survival (OS) in advanced NSCLC treated with systemic therapy. The analysis included data from the phase I/II CP1108 study (NSCLC Durvalumab cohort) and the chemotherapy arm of the phase III MYSTIC trial. We also analyzed data from Dana-Farber Cancer Institute (DFCI) cohorts receiving immunotherapy alone or in combination with chemotherapy. Baseline and follow-up (FU) CT scans were collected and analyzed using deep neural networks for automatic L3 slice selection and body compartment segmentation (skeletal muscle [SM], subcutaneous adipose tissue [SAT], and visceral adipose tissue [VAT]). We compared OS based on baseline BC measures or their change at the first FU scan. The impact of sarcopenia at baseline was evaluated in association with the delta metrics.

RESULTS

A total of 1865 NSCLC patients were analyzed, of which 222 were treated on CP1108, 257 were treated on MYSTIC, 870 received IO monotherapy at DFCI (DFCI-IO), and 516 received chemoimmunotherapy at DFCI (DFCI-CIO). The median ages were 65, 63, 66, and 65, respectively. A loss in SM mass >5%, as indicated by a change in L3 SM area, was significantly associated with poorer OS across all patient groups (median [months]: 5 vs. 19; p<0.001 for CP1108, 11 vs. 14; p = 0.03 for MYSTIC, 11 vs. 17; p<0.001 for DFCI-IO, and 12 vs. 22; p<0.001 for DFCI-CIO). This effect was driven by male patients, with a non-significant association (p>0.5) among female patients in the MYSTIC and DFCI-CIO cohorts. An increase in SAT density >5%, as quantified by the average CT attenuation in HU of the SAT compartment, was significantly linked to poorer OS in three patient groups (median [months]: 4 vs. 19; p<0.001 for CP1108, 10 vs. 17; p<0.001 for DFCI-IO, and 12 vs. 20; p = 0.003 for DFCI-CIO). This was primarily observed among female patients, with a non-significant association (p>0.5) among male patients in the DFCI-CIO cohort. On subgroup analysis, loss in SM mass had an impact on OS in patients with baseline sarcopenia (median [months] 5 vs. 22; p<0.001 for CP1108, 5 vs. 12; p = 0.03 for MYSTIC, 11 vs. 17; p<0.001 for DFCI IO, and 9 vs. 17; p = 0.003 for DFCI-CIO). Conversely, no association was observed between change in SM mass and OS in patients without sarcopenia at baseline in the MYSTIC and DFCI-IO cohorts.

CONCLUSION

Sarcopenia and loss in SM mass during systemic therapy for NSCLC are markers of poor outcome, especially in male patients. SAT density changes are also strongly associated with prognosis, particularly in female patients. Automated CT-derived BC measurements should be considered along with other risk factors in determining lung cancer prognosis and ability to tolerate oncologic treatments.

Pre-Brachytherapy Diffusion-Weighted Magnetic Resonance Imaging (DW-MRI) Response as Predictor of Local Control in the Definitive Treatment of Cervical Cancer

PURPOSE/OBJECTIVE(S)

Chemoradiation consisting of external beam radiotherapy (EBRT) followed by brachytherapy (BT) is the standard of care for Stage IB2-IVA cervical cancer (CC). Multi-parametric MRI (mpMRI) is a valuable tool for initial staging, treatment planning and response assessment. In this study, we aim to explore the potential of mpMRI, in particular DW-MRI, to predict overall tumor control following chemoradiation in CC.

MATERIALS/METHODS

We identified 78 consecutive patients treated with chemoradiation for FIGO IB2-IVA CC between 2012-2020, who had an MRI at baseline (MRb) and post-EBRT prior to brachytherapy boost (MRpb) that included DW-MRI (b-value = 0 and 800 s/mm2). Median age was 53 years, most patients had squamous cell carcinoma (76.9%) and advanced-stage disease (56.4% stage IIIA-IVA). Median time from completion of EBRT to MRpb was 3 days. Regions of interest (ROI) in primary tumor were delineated on DW image (b = 0 s/mm2) using ITK-SNAP software. DW-MRI data were fitted to a monoexponential model to calculate apparent diffusion coefficient (ADC) values using in-house software platform (MRI-QAMPER). MRpb mean ADC values (n = 78) and relative changes (%) in mean ADC values between MRb and MRpb (n = 64) were correlated with outcomes, including local failure (LF), regional or distant failure (RDF), and failure at any site (FAS), with death without failure as a competing risk. Median follow-up time was 45 months (95% CI 38, 53).

RESULTS

At first post treatment assessment, 72 patients (92.3%) had a complete response (CR) in the cervix and 68 patients (87.2%) had CR in all disease sites. Of patients who had CR in the cervix (n = 72), only 1 patient had local recurrence. Of patients who had CR in all disease sites, 10 later recurred (1 LF only, 1 LF&RDF, 8 RDF only). Overall, 7 patients (9%) had LF, and 19 patients (24.4%) had FAS. A higher mean ADC value in MRpb was associated with LF (HR 4.3, 95% CI 1.32, 14.6; P = 0.016), but not with RDF (P = 0.4) or FAS (P = 0.5). A higher relative change in the mean ADC value between MRb and MRpb was associated with a lower risk of LF (HR 0.94, 95% CI 0.90, 0.98; P = 0.002), but not with RDF (P = 0.8) or FAS (P = 0.4).

CONCLUSION

Treatment response as measured on prebrachytherapy DW-MRI is a significant predictor of local control in patients undergoing chemoradiation for stage IB2-IVA CC. ADC values, a quantitative imaging biomarker on MRpb may be instrumental in dose intensification/de-escalation efforts in CC.

Tumor Cell-Intrinsic PD-L1 Effects on Radiation-Induced Locoregional Antitumor Immunity

PURPOSE/OBJECTIVE(S)

Targeting PD-L1 is a beneficial strategy to reinvigorate antitumor immunity, however variable response and resistance are challenging and suggest the need for multimodality approaches. Tumor cell-intrinsic PD-L1 signals also regulate non-canonical pathogenic pathways that may impact treatment resistance. Ionizing radiation (IR) can induce antitumor immunity and has demonstrated therapeutic synergy with immunotherapy in some cases, however tumor-driven immunologic mechanisms affecting clinical outcomes remain incompletely understood. In this study, we investigated the impact of tumor cell-intrinsic PD-L1 signals on IR-induced locoregional immune response and tumor control.

MATERIALS/METHODS

We used orthotopic B16-F10 melanoma (WT-B16) and 4T1 triple negative breast cancer (WT-4T1) murine tumor models, as well as PD-L1 disabled variants (KO) generated by CRISPR/Cas9, implanted bilaterally. IR (10 Gy) was targeted at one tumor alone to evaluate both direct and indirect IR effects based on tumor PD-L1 status. We evaluated response by tumor volume (TV) measurements, flow cytometry of tumor-infiltrating lymphocytes (TILs) and tumor draining lymph nodes (TDLNs) in both irradiated and unirradiated compartments, and granzyme B (GZB) PET imaging to assess functional in vivo changes. Chemokine-based multiplex assays were used to assess cell lines receiving IR (4Gy) and ex vivo tumor lysates and serum.

RESULTS

IR-induced local tumor control was not significantly affected based on tumor PD-L1 status, however deactivation of tumor cell PD-L1 enhanced IR-induced regional tumor control. Unirradiated WT tumors in mice harboring irradiated KO but not irradiated WT tumors demonstrated a significant mean reduction in TV with instances of complete distant tumor regression. PET imaging demonstrated a nearly 2-fold higher concentration of GZB in KO versus WT tumors, in line with known locally immunosuppressive effects of tumor PD-L1. Remarkably, GZB levels were >1.5-fold higher in unirradiated WT tumors in mice harboring an irradiated KO versus WT tumor, which correlated with a 50% increase in PD-1+CD8+ T cells. Higher levels of CD62+CD44- naïve CD4+ (4-fold) and CD8+ (2-fold) memory T cells were seen in TDLNs of irradiated KO versus WT tumors. Cytokine levels positively correlated with immune recruitment and activation status, as CXCL10, CCL2 and CCL5 were significantly upregulated in PD-L1 KO versus WT tumors cells.

CONCLUSION

Results from this study demonstrate cell-intrinsic PD-L1 inhibits IR-induced locoregional immune activation and frequency of regional tumor control, with clinical implications including therapeutic targeting of tumor cell-intrinsic PD-L1 signals to enhance IR-induced immunogenicity, utility of IR based on tumor PD-L1 status particularly in the metastatic setting, and immunotherapy combinations. Future studies investigating mechanisms of resistance to IR-induced immune activation to enhance responsiveness are warranted.

The axial and sagittal CT values of the 7th thoracic vertebrae in screening for osteoporosis and osteopenia

AIM

To evaluate the difference in computed tomography (CT) attenuation value of different planes of the 7th thoracic vertebra and investigate the efficacy of axial and sagittal vertebral CT measurements in predicting osteoporosis.

MATERIALS AND METHODS

Patients who underwent routine chest CT and dual-energy X-ray absorptiometry (DXA) within 1 month were included in this retrospective study. The CT attenuation values of different planes were compared. Logistic regression and receiver operating characteristic (ROC) were used to analyse the difference of each plane in the diagnosis of osteoporosis.

RESULTS

The study included 1,338 patients (mean age of 61.9±11.9; 54% female). The CT attenuation values decreased successively in the normal group, osteopenia group, and osteoporosis group. The paired t-test results showed that the mid-axial measurements were greater than mid-sagittal measurements, with a mean difference of 9 HU, the difference was statistically significant (p<0.001, 95% confidence interval [CI] = 7.8-10.1). For each one-unit reduction in mid-sagittal CT attenuation value, the risk of osteopenia or osteoporosis increased by 3.6%. To distinguish osteoporosis from non-osteoporosis (osteopenia + normal), the sensitivity was 90% and the specificity was 52.4% at the mid-sagittal threshold of 113.7 HU.

CONCLUSIONS

The CT attenuation values of mid-sagittal plane have higher diagnostic efficacy than axial planes in predicting osteoporosis. For patients with a sagittal CT attenuation value of <113.7 HU in the T7, further DXA examination is warranted.

Florida-California Cancer Health Equity Center (CaRE2) Community Scientist Research Advocacy Program

The Community Scientist Program (CSP), a model connecting researchers with community members, is effective to inform and involve the general population in health-related clinical research. Given the existing cancer disparities among Black/African American and Hispanic/Latino/a populations, more models describing how cancer-related CSPs are designed, implemented, and evaluated are needed. The Florida-California Cancer Research, Education and Engagement (CaRE2) Health Equity Center is a tri-institutional, bicoastal center created to eliminate cancer health disparities among Black/African American and Hispanic/Latino/a populations living in California and in Florida. The CaRE2 Center created a Community Scientist Research Advocacy (CSRA) training program for community members to become cancer research advocates. The CSRA program is currently a 13-week program conducted 100% virtually with all materials provided in English and Spanish for participants to learn more about prostate, lung, and pancreas cancers, ongoing research at CaRE2, and ways to share cancer research throughout their communities. Participants attend didactic lectures on cancer research during weeks 1-5. In week 4, participants join CSRA self-selected groups based on cancer-related topics of interest. Each group presents their cancer-related advocacy project developed during weeks 5-12 at the final session. In this paper, we describe the CaRE2 Health Equity Center's CSRA program, share results, and discuss opportunities for improvement in future program evaluation as well as replication of this model in other communities.

Stereotactic Radiotherapy or Whole Brain Radiotherapy Combined with Pyrotinib and Capecitabine in HER2-Positive Advanced Breast Cancer Patients with Brain Metastases (BROPTIMA): A Prospective, Phase Ib/II Single-Arm Clinical Study

PURPOSE/OBJECTIVE(S)

Approximately half of patients with advanced HER2-positive breast cancer (BC) will develop brain metastases (BM) over time. Local therapy including stereotactic radiotherapy (SRT) and whole brain radiotherapy (WBRT) is the main initial treatment in malignant tumor patients with BM. However, more than 50% patients after radiotherapy in one year suffered intracranial recurrence. Pyrotinib, a small molecule, irreversible, pan-ErbB receptor tyrosine kinase inhibitor (TKI), has a high potency for controlling BM and reducing the occurrence of brain metastases in advanced HER2-positive BC patients. We hypothesized that SRT or WBRT combined with pyrotinib and capecitabine could decrease intracranial progression in HER2 positive BC with newly diagnosed BM.

MATERIALS/METHODS

In this prospective single-arm phase Ib/II trial (NCT04582968), eligible patients were assigned to either fractionated stereotactic radiotherapy (FSRT) or whole-brain radiation therapy (WBRT), combined with pyrotinib and capecitabine. The primary endpoint was one-year CNS progression-free survival (PFS) rate. Secondary endpoints included intracranial objective response rate (IC-ORR) according to RANO-BM criteria, progression-free survival (PFS), overall survival (OS) and evaluation of safety and neurocognitive function.

RESULTS

From January 2020 to August 2022, 40 patients were enrolled. Twenty-nine patients were treated with FSRT in 8 Gy per fraction with 3 to 5 fractions and 11 were treated with WBRT in 3 Gy per fraction with 10 fractions, and then received chemotherapy in a time frame starting from 0 to 7 days after radiotherapy. At a median follow-up of 17.3 months, 1-year CNS-PFS rate was 74.9% (95% CI 61.9-90.7%) and median CNS-PFS was 18 months (95% CI, 15.5 to NA months). One-year PFS rate was 66.9% (53.1-84.2%) and median PFS time was 17.6 months (95% CI 12.8-34.1 months). The best intracranial response rate (IC-ORR: complete response and partial response) was 92.5% (37/40). The most common grade 3 or worse toxicity was diarrhea (7.5%) and asymptomatic radiation necrosis was detected in 4 of 67(6.0%) lesions treated with FSRT. No differences of neurocognitive function evaluated by MMSE (Mini-Mental State Exam) were observed between different groups at any time point.

CONCLUSION

Radiotherapy combined with pyrotinib and capecitabine resulted in a promising efficacy that crossed the pre-specified boundary in patients with HER2-positive advanced breast cancer with brain metastases. This is the first prospective study showing the efficacy and safety of CNS radiotherapy concurrent with pyrotinib and capecitabine in patients with BM from HER2-positive breast cancer. Further investigation in a randomized controlled study is warranted.

The effect of ticagrelor on myocardial microcirculation, cardiac function, and adverse cardiovascular events in STEMI patients after PCI

OBJECTIVE

This study aimed to investigate the effects of ticagrelor on myocardial microcirculation, cardiac function, and adverse cardiovascular events in ST-segment elevation myocardial infarction (STEMI) patients after percutaneous coronary intervention (PCI).

PATIENTS AND METHODS

A total of 80 STEMI patients admitted to our hospital from February 2020 to March 2023 were selected and included in the retrospective study, all receiving PCI treatment. They were randomly and retrospectively divided into a control group (40 cases) and an observation group (40 cases), and treated with clopidogrel and ticagrelor, respectively. The clinical effects were compared.

RESULTS

The starting perfusion time of the contrast agent in the myocardial infarction area in the observation group was 2.22±0.27 s, and the peak perfusion time was 2.62±0.27 s, which was lower than those in the control group (2.51±0.29 s and 3.21±0.39 s, t=4.629, 7.867, p=0.000). The ratio of peak perfusion intensity between the two groups was significantly different (t=2.363, p=0.021). Left ventricular ejection fraction, stroke volume index, and cardiac index in the observation group were higher than those in the control group (55.03±6.03 vs. 52.33±5.13; 57.39±6.81 vs. 51.11±6.31 L/min·m-2; 3.49±0.45 vs. 3.12±0.38 mL/m2, t=2.157, 4.278, 3.973, p<0.05). The observation group had lower levels of brain natriuretic peptide and C-reactive protein compared to the control group (425.35±55.71 vs. 589.36±70.24 pg/mL; 15.13±1.03 vs. 21.64±2.74 mg/L; t=11.570, 14.066, p=0.000). There was no statistical significance in the incidence of adverse cardiovascular events between the two groups (2.50% vs. 7.50%, χ2=1.920, p=0.166).

CONCLUSIONS

The use of ticagrelor can regulate myocardial microcirculation and improve cardiac function in STEMI patients undergoing PCI.

Use of Explainable AI Algorithm Revealing Longitudinal Changes in Practice Patterns and Toxicity Models

PURPOSE/OBJECTIVE(S)

Dosimetric constraints evolve as clinicians implement practice changes, requiring modeling approaches to be dynamic. We applied a semi-automated explainable artificial intelligence (eAI) algorithm and dashboard visualizations to model dysphagia and xerostomia for head and neck cancer patients. We coupled a large, comprehensive, "real-world" database to the eAI for discovery of features with the strongest combined statistical and machine learning based evidence and to identify clinically actionable thresholds.

MATERIALS/METHODS

Cohort included 758 patients treated 2017-2021 for HN cancer with conventional fractionation. Features included age, sex, diagnosis, staging, chemotherapy, smoking and alcohol status, BMI, weight loss, re-simulation, DVH curves, PTV and OAR volumes. Patients were scored for toxicity within 2 yrs of RT for dysphagia grade ≥ 3 and xerostomia grade ≥ 2. Bootstrap resampling of thresholds, ROC-AUC, PR-ROC, SN, SP, F1 and diagnostic odds ratio was used to statistically profile strength of evidence for candidate features. XGBoost models with 10-fold cross validation were repeated (n = 20) to identify mean and CIs for statistical measures of predictions. DVH metrics included standard template values and those with highest statistical evidence and low cross correlation with other features. Backward feature selection was used to identify the most relevant feature subset, where the least informative feature is iteratively removed from the model. This workflow was repeated by year and overall.

RESULTS

Annual incidence of dysphagia averaged 0.13 ± 0.02 overall years. Xerostomia incidence decreased from 0.32 to 0.12 (2017-2021). Box-whisker plots by year showed consistent reductions in standard practice toxicity linked DVH metric values. Median dose to superior constrictors (PCM), contralateral parotid and contralateral submandibular gland (SMG) declined from 2017 to 2021 by 48 to 33 Gy, 17 to 10 Gy, and 28 to 22 Gy respectively. Statistics of XGBoost models of dysphagia for all years were ROC-AUC = 0.72 ± 0.05. Strongest overall years predictors were Oral Cavity (OC) D50%[Gy] < 32, inferior PCM Max [Gy] < 60, contralateral SMG D10%[Gy] < 53 and use of Paclitaxel. Xerostomia models were less predictive with ROC-AUC = 0.65 ± 0.05. Strongest predictors over each year were ipsilateral parotid D30%[Gy] < 35, contralateral SMG D96%[Gy] < 18.4, and overall staging < II. Predictive features varied substantially by year for both, showing the most consistency for SMG doses. For example, OC D50%[Gy] < 27 and contralateral SMG D96%[Gy] < 18 dominated xerostomia model in 2017 but not in 2021 when practice norms shifted to lower doses.

CONCLUSION

As OAR doses were systematically reduced, statistical and AI models evidence highlighted contralateral SMG dose as important to both dysphagia and xerostomia for clinical practice change. The "real-world" database + eAI + visualization dashboards provided a method for continuous learning as clinical practice changes.

A Pilot Study of Stereotactic Body Radiotherapy and 177Lu-PSMA-617 for Oligometastatic Hormone Sensitive Prostate Cancer

PURPOSE/OBJECTIVE(S)

Stereotactic body radiotherapy (SBRT) is increasingly used for oligorecurrent prostate cancer (OPC). Despite excellent local control, distant metastasis free survival rates are more modest. We hypothesized SBRT outcomes could be optimized with improved staging imaging and integration of a well-tolerated targeted radiopharmaceutical therapy (RLT) for microscopic disease. We report initial results of a prospective, single-institution pilot (NCT05079698) of a novel, PSMA-based theranostic strategy for OPC.

MATERIALS/METHODS

Men with castrate sensitive OPC and 1-3 sites of PSMA PET avid disease ("index lesions") and no PSMA non-avid sites were eligible. No androgen deprivation therapy was permitted. Subjects first received 2 cycles of 177Lu-PSMA-617 RLT (7.47±0.14 GBq) spaced 6 weeks apart. In vivo dosimetry was performed during cycle 1. Four weeks post-cycle 2, patients were restaged with 68Ga-PSMA PET for an interim (post-RLT) response assessment. Index lesions were then consolidated with SBRT (9 Gy x 3) irrespective of post-RLT PET response. The primary outcome was feasibility defined as successful completion of protocol-mandated therapy without intercurrent distant failure on post-RLT PET.

RESULTS

Six men were treated with nine total index lesions (5 nodal, 3 osseous, 1 visceral). The study met its primary endpoint; all completed required interventions and no distant progression was seen on interim PSMA PET. Treatment was well tolerated; no grade 3+ toxicities, 2/6 had grade 2 toxicities (transient anemia and hyperbilirubinemia) and 5/6 had grade 1 toxicities. Median baseline lesion-level PSMA SUVmax was 16.8±8.7. Median interim SUVmax was 6.2±2.5 and declined for all but one lesion post-RLT (median -65%). Median SUVmax at 3-mos post-SBRT was 3.3±2.5 and decreased for all evaluable lesions (median -80%). Median baseline PSA was 2.01 ng/mL (range: 0.72-4.56) which declined in 5/6 post-RLT. The 6th patient experienced biochemical rise with interim PET showing only greater avidity in the known index lesion and SBRT was completed per protocol. All 4 evaluable patients with at least one post-SBRT follow-up have improved PSA at last visit (range 5.5-12 mos from cycle 1), and 2/4 have undetectable PSA. Composite dosimetry, correlatives and quality of life studies are forthcoming.

CONCLUSION

Our pilot study demonstrates the feasibility of a novel PSMA anchored theranostic strategy combining SBRT with targeted RLT for OPC. Preliminary data suggests promising outcomes, including the possibility of achieving an undetectable biochemical disease state without hormone therapy.

Oncotype Recurrence Score (RS) at the Extremes of Tumor Size: Which Drives Clinical Outcomes?

PURPOSE/OBJECTIVE(S)

Tumor size is an established and independent risk factor for local-regional recurrence (LRR) and distant recurrence (DM). More recently, the recurrence score calculated from a 21-gene expression assay (Oncotype DXTM, Exact Sciences) has also been correlated with LRR and DM. We sought to determine the impact of the interaction between tumor size and Oncotype RS, particularly when the variables are in discrepancy with each other. More specifically, we evaluated clinical outcomes in patients with small tumors (≤1 cm) and high RS (≥26) and, separately, in patients with large tumors (>5 cm) with low RS.

MATERIALS/METHODS

Between 2008 and 2020, 310 patients were identified retrospectively as having been treated for early-stage, hormone-receptor positive, Her2-negative breast cancers with tumor size ≤1 cm that were node-negative and had RS ≥ 26 at our institution. In addition, 64 patients were identified with tumor size >5 cm and RS < 26 (irrespective of nodal status). Locoregional recurrence rates (LRR) and invasive recurrence rates (composite of LRR and distant recurrence) were estimated using the Kaplan-Meier method.

RESULTS

Patient characteristics are shown in Table 1. In the group of patients with small tumors and high RS, the 5- and 10-year invasive recurrence rates with 95% CI were 8% (4.2-12) and 17% (8.2-26). The 5- and 10-year locoregional recurrence rates with 95% CI were 5.8% (2.7-8.8) and 15% (6.2-23). In the group of patients with large tumors and low RS, 10-year rates could not be estimated with the available data. The 5- and 8-year invasive recurrence rates with 95% CI were 3.2% (0-7.5) and 3.2% (0-7.5). The 5- and 8-year locoregional recurrence rates with 95% CI were 1.6% (0-4.7) and 1.6% (0-4.7).

CONCLUSION

Our findings suggest that patients with small tumors and high RS are at a higher risk for LRR compared to the average ≤1 cm node-negative breast cancer based on published data on the effect of tumor size on LRR and DM. Similarly, tumors larger than 5 cm with low RS appear to behave indolently and in a manner consistent with more favorable risk (despite their large size). These findings may have important implications for the tailoring of local-regional treatment strategies.

Favorable Toxicity and Local Control with Ultrahypofractionated Radiation Therapy (UH-RT) for Melanoma of the Lower Genital Tract (LGT)

PURPOSE/OBJECTIVE(S)

To report our experience using UH-RT +/- immunotherapy (IO) in women with melanoma of the LGT.

MATERIALS/METHODS

We retrospectively identified 23 patients who received UH-RT to primary tumor for vulvovaginal melanoma from 2012 to 2022. Median age was 69 years (IQR: 62-76). Stage included localized, node positive, or metastatic. 18 (78%) had tumors involving the vagina/cervix and 5 (22%) had vulvar tumors. 6 patients had c-KIT mutations; 13 patients were wild-type; 4 patients were unknown. 12 (52%) were treated at initial presentation (cohort A) and 11 (48%) at local progression/recurrence following prior therapy (cohort B). In cohort A, most (n = 11) received concurrent IO. In cohort B, 3 recurred after surgery alone, 4 after systemic therapy alone and 4 after surgery and systemic therapy. RT consisted of 6 Gy x 6 (n = 11), 6 Gy x 5 (n = 10) and 5 Gy x 5-6 (n = 2) delivered to the primary tumor + 0.5 cm margin. Patients initiated IO either ≥3 months preRT (n = 8), concurrent with RT (n = 12) or ≥3 months following RT (n = 2). 1 patient in cohort B did not receive IO. Toxicity was graded using CTCAE v 5. Overall survival (OS) was measured from end of RT. Cumulative incidence of local progression was measured from end of RT. Kaplan-Meier method and Cox regression were used for survival analyses. Landmark method was used for timing of IO. Median follow-up as determined by reverse Kaplan-Meier method was 60 months (95% CI: 37-N/A).

RESULTS

Overall incidence of acute/late grade 2+ toxicity for the entire cohort was 34%. Grade 2 acute toxicity included: dermatitis (n = 3), urinary (n = 2), vaginitis (n = 2) and diarrhea (n = 1). 3 patients experienced grade 3 acute dermatitis. 1 patient experienced late grade 2 vaginitis. No grade 3 or 4 toxicity was noted. No significant differences in toxicity were noted between RT regimens. Local disease control was achieved in 61% of patients. Local only, local and distant, and distant-only progression were seen in 17%, 22%, and 30% of patients respectively. 2-year cumulative incidence of local progression was 33% for the whole cohort, 28% for cohort A, and 36% for cohort B (p = 0.4). On UVA, factors associated with local progression were vulvar disease (p = 0.02) and c-KIT mutation (p = 0.011). No significant difference in local control was noted based on biologic effective dose (BED10 < = 48Gy vs >48Gy) (p = 0.06). Median OS for entire cohort, cohort A, and cohort B were 46, 72, and 30 months, respectively. 2-year survival (95% CI) was 67% (50%-91%), 73% (51%-100%), and 64% (41%-99%) respectively. On UVA, non-local disease at time of RT (p = 0.016) and receipt of IO ≥3 months prior to RT (p = 0.030) had worse OS.

CONCLUSION

UH-RT+/- IO for melanoma of the LGT is well-tolerated with local disease control achieved in 61% of patients. Vulvar primary and c-Kit mutations were associated with worse local control. Additional follow-up may be necessary to determine the value of dose escalation.

An evolutionary epigenetic clock in plants

Molecular clocks are the basis for dating the divergence between lineages over macroevolutionary timescales (~105 to 108 years). However, classical DNA-based clocks tick too slowly to inform us about the recent past. Here, we demonstrate that stochastic DNA methylation changes at a subset of cytosines in plant genomes display a clocklike behavior. This "epimutation clock" is orders of magnitude faster than DNA-based clocks and enables phylogenetic explorations on a scale of years to centuries. We show experimentally that epimutation clocks recapitulate known topologies and branching times of intraspecies phylogenetic trees in the self-fertilizing plant Arabidopsis thaliana and the clonal seagrass Zostera marina, which represent two major modes of plant reproduction. This discovery will open new possibilities for high-resolution temporal studies of plant biodiversity.

[Analysis of the 1-year curative efficacy of sleeve gastrectomy, Roux-en-Y gastric bypass, single anastomosis duodenal-ileal bypass with sleeve gastrectomy and biliopancreatic diversion with duodenal switch in patients with super obesity]

Objective: To evaluate the 1-year postoperative efficacy of four bariatric procedures, namely sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), single anastomosis duodenal-ileal bypass with sleeve gastrectomy (SADI-S), and biliopancreatic diversion with duodenal switch (BPD/DS) for treating super obesity. Methods: In this retrospective observational study, we analyzed the clinical data of 40 patients with super obesity (body mass index [BMI]≥50 kg/m2) who had undergone bariatric surgery in the China-Japan Union Hospital of Jilin University from November 2015 to December 2020. The study cohort consisted of 21 men and 19 women of average age 31.7±9.0 years. The preoperative weight and BMI were (159.2±16.9) kg and (53.4±3.0) kg/m2, respectively. Prior to the surgery, 30 individuals had hypertension, 27 hyperuricemia, 15 type 2 diabetes, 10 abnormally high total cholesterol, 20 abnormally high triglycerides, and 24 abnormally high low-density lipoprotein. We divided the participants into four groups according to the type of operation: SG group (n=16), RYGB group (n=9), SADI-S group (n=9) and BPD/DS group (n=6). We examined the following factors: weight, BMI, excess weight loss (%), total weight loss (%), and remission of preoperative metabolic diseases (including hypertension, hyperuricemia, type 2 diabetes, and hyperlipidemia) 3, 6, and 12 months after surgery. The variables assessed for hypertension were systolic and diastolic blood pressure; for type 2 diabetes, glycated hemoglobin; and for hyperlipidemia, total cholesterol, triglycerides, and low-density lipoprotein 1-year after the surgery. The safety of surgery was also assessed. Results: All patients successfully completed laparoscopic procedures, none of them requiring conversion to laparotomy. The amount of blood loss during surgery was less than 50 mL. Postoperative hospital stay was 6-16 days. There were no deaths during the perioperative period. However, two postoperative complications occurred in the RYGB group, namely bleeding and anastomotic leakage. No complications were detected in the other groups. At 3, 6, and 12 months after surgery, percentage of excess weight loss was 36.6±11.0, 62.4±15.7, and 68.2±16.0 (F=21.830, P<0.001) in the SG group; 30.6±6.9, 42.5±5.8, and 50.6±11.1 (F=13.222, P<0.001) in the RYGB group; 39.7±7.8, 54.6±12.7, and 81.9±12.0 (F=33.821, P<0.001) in the SADI-S group; and 40.2±4.8, 57.7±11.8, and 82.8±14.9 (F=21.552, P<0.001), respectively, in the BPD/DS group. The percentage of excess weight loss increased significantly over the 12-month observation period in all groups . Compared with before surgery, hypertension and hyperuricemia in the SG, SADI-S, and BPD-DS groups showed significant improvement after one year (all P<0.05). However, only the SADI-S group exhibited a significant decrease in glycosylated hemoglobin concentrations (P=0.038). Only the BPD-DS group showed significant decreases in various indicators of hyperlipidemia (all P<0.05). The improvements in obesity-related complication indexes did not reach statistical significance in the RYGB group (all P>0.05). Conclusion: SG, RYGB, SADI-S and BPD/DS are all safe and effective treatments for super obesity. All of these procedures can improve the associated metabolic diseases to a certain extent.

Measurement of the Lifetime and Λ Separation Energy of _{Λ}^{3}H

The most precise measurements to date of the _{Λ}^{3}H lifetime τ and Λ separation energy B_{Λ} are obtained using the data sample of Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV collected by ALICE at the LHC. The _{Λ}^{3}H is reconstructed via its charged two-body mesonic decay channel (_{Λ}^{3}H→^{3}He+π^{-} and the charge-conjugate process). The measured values τ=[253±11(stat)±6(syst)]  ps and B_{Λ}=[102±63(stat)±67(syst)]  keV are compatible with predictions from effective field theories and confirm that the _{Λ}^{3}H structure is consistent with a weakly bound system.

Universal DNA methylation age across mammalian tissues

Aging, often considered a result of random cellular damage, can be accurately estimated using DNA methylation profiles, the foundation of pan-tissue epigenetic clocks. Here, we demonstrate the development of universal pan-mammalian clocks, using 11,754 methylation arrays from our Mammalian Methylation Consortium, which encompass 59 tissue types across 185 mammalian species. These predictive models estimate mammalian tissue age with high accuracy (r > 0.96). Age deviations correlate with human mortality risk, mouse somatotropic axis mutations and caloric restriction. We identified specific cytosines with methylation levels that change with age across numerous species. These sites, highly enriched in polycomb repressive complex 2-binding locations, are near genes implicated in mammalian development, cancer, obesity and longevity. Our findings offer new evidence suggesting that aging is evolutionarily conserved and intertwined with developmental processes across all mammals.

Effects of Yi Jin Jing on juvenile cervical spondylopathy in China: A parallel, randomized, assessor-blinded clinical trial

Background

Cervical spondylopathy is a common musculo-articular disorder, multiple exercises are recommended. Chinese fitness exercises are prevalent and used to treat various diseases.

Aim

To explore the efficacy of Chinese fitness exercise Yi Jin Jing exercise in intervening the cervical spondylopathy in adolescents.

Patients and Methods

The study was conducted in 60 adolescent patients with cervical spondylopathy, with 30 patients in each group.

Methods

The study was conducted in 60 adolescent patients with cervical spondylopathy, with 30 patients in each group. The observation group was required to take Yi Jin Jing exercise, and the control group took the brisk walking exercise. The first week was the preparatory period for the patients, and then the participants were required to do exercises three times a week for at least 30 minutes in the later 3 weeks. Before and after treatment, Neck Disability Index (NDI) scores, pain visual analog scale (VAS) scores, and cervical curvature in both groups were observed, and the incidence of adverse events in both groups was recorded during the trial.

Results

The NDI and VAS scores in both groups statistically decreased after intervention and mildly increased at follow-up, while the reduction in scores of the Yi Jin Jing group was more significant. Cervical curvature in both groups improved on day 28 compared to day 0. There were no adverse reactions during the evaluation period.

Conclusion

The Chinese health-care qigong Yi Jin Jing exercise is more effective than brisk walking in improving the cervical range of motion and relieving pain in adolescents with cervical spondylopathy. Trial registration/Protocol registration: Clinical Trial Registry (ChiCTR2000030723).

Latent TB and depressive symptoms in household contacts of persons with active TB

BACKGROUND: Depression is common among persons with TB and is associated with poor clinical outcomes. However, little is known about the relationship between latent TB infection (LTBI) and depression. We assessed the association between LTBI and depressive symptoms among household contacts (HHCs) of patients receiving TB treatment.METHODS: We enrolled 1,009 HHCs of 307 patients receiving TB treatment in Lima, Peru, during 2016-2018. At enrollment, HHC LTBI status was assessed using the interferon-gamma release assay (IGRA). Depressive symptoms were assessed at baseline and 12 months later using the Patient Health Questionnaire-9 (PHQ-9) with a cut-off of ≥5. We used logistic regression to estimate the odds ratio (OR) for PHQ-9 ≥5, comparing HHCs with and without baseline LTBI.RESULTS: Among 921 HHCs, 374 (41.0%) had LTBI at baseline, and 69 (12.4%) of 567 HHCs had PHQ-9 ≥5. Compared to HHCs without LTBI at enrollment, those with LTBI had almost two times the odds of PHQ-9 ≥5 at follow-up after controlling for potential confounders (adjusted OR 1.93, 95% CI 1.09-3.39); this association was driven by greater severities of depressive symptoms.CONCLUSION: HHCs with LTBI had increased odds of depressive symptoms 1 year later. This population may benefit from mental health screening and interventions integrated into TB programs.

A modified triangular flap suture method used for inferior third molar extraction: A three-arm randomized clinical trial for the assessment of quality of life

BACKGROUND

The purpose of this study is to explore whether decreasing the number of sutures can improve the quality of life after inferior third molar extraction.

MATERIAL AND METHODS

This study used a three-arm randomized design that included 90 individuals. Patients were randomized and divided into three groups-the airtight suture group (traditional), the buccal drainage group, and the no-suture group. Postoperative measurements, including treatment time, visual analog scale, questionnaire on postoperative patient quality of life, and details about trismus, swelling, dry socket, and other postoperative complications were obtained twice and the mean values were recorded. To verify the normal distribution of the data, the Shapiro-Wilk test was performed. The statistical differences were evaluated using the one-way ANOVA and the Kruskal-Wallis test with Bonferroni post-hoc correction.

RESULTS

The buccal drainage group showed a significant decrease in postoperative pain and better speech ability than the no-suture group on the 3st day, with a mean of 1.3 and 0.7 (P < 0.05). The airtight suture group also showed similar eating and speech ability, which was better than the no-suture group, with a mean of 0.6 and 0.7 (P < 0.05). However, no significant improvements were noted on the 1st and 7th days. The surgical treatment time, postoperative social isolation, sleep impairment, physical appearance, trismus, and swelling showed no statistical difference between the three groups at all measured times (P > 0.05).

CONCLUSIONS

Based on the above findings, the triangular flap without a buccal suture may be superior to the traditional group and no-suture group in less pain, and better postoperative patient satisfaction in the first 3 days and may be a simple and viable option in clinical practice.

Erratum: Global Polarization of Ξ and Ω Hyperons in Au+Au Collisions at sqrt[s_{NN}]=200 GeV [Phys. Rev. Lett. 126, 162301 (2021)]

This corrects the article DOI: 10.1103/PhysRevLett.126.162301.

Measurements of jet multiplicity and jet transverse momentum in multijet events in proton-proton collisions at s=13TeV

Multijet events at large transverse momentum (p T ) are measured at s = 13 Te V using data recorded with the CMS detector at the LHC, corresponding to an integrated luminosity of 36.3 fb - 1 . The multiplicity of jets with p T > 50 Ge V that are produced in association with a high-p T dijet system is measured in various ranges of the p T of the jet with the highest transverse momentum and as a function of the azimuthal angle difference Δ ϕ 1 , 2 between the two highest p T jets in the dijet system. The differential production cross sections are measured as a function of the transverse momenta of the four highest p T jets. The measurements are compared with leading and next-to-leading order matrix element calculations supplemented with simulations of parton shower, hadronization, and multiparton interactions. In addition, the measurements are compared with next-to-leading order matrix element calculations combined with transverse-momentum dependent parton densities and transverse-momentum dependent parton shower.

Strong Constraints on Jet Quenching in Centrality-Dependent p+Pb Collisions at 5.02 TeV from ATLAS

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.

Search for Heavy Neutral Leptons in Decays of W Bosons Using a Dilepton Displaced Vertex in sqrt[s]=13 TeV pp Collisions with the ATLAS Detector

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 Collapse

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Azimuthal correlations in Z +jets events in proton-proton collisions at s=13TeV

The production of Z bosons associated with jets is measured in pp collisions at s = 13 Te V with data recorded with the CMS experiment at the LHC corresponding to an integrated luminosity of 36.3fb - 1 . The multiplicity of jets with transverse momentum p T > 30 Ge V is measured for different regions of the Z boson's p T ( Z ) , from lower than 10Ge V to higher than 100Ge V . The azimuthal correlation Δ ϕ between the Z boson and the leading jet, as well as the correlations between the two leading jets are measured in three regions of p T ( Z ) . The measurements are compared with several predictions at leading and next-to-leading orders, interfaced with parton showers. Predictions based on transverse-momentum dependent parton distributions and corresponding parton showers give a good description of the measurement in the regions where multiple parton interactions and higher jet multiplicities are not important. The effects of multiple parton interactions are shown to be important to correctly describe the measured spectra in the low p T ( Z ) regions.

Search for Higgs Boson Decay to a Charm Quark-Antiquark Pair in Proton-Proton Collisions at sqrt[s]=13 TeV

A search for the standard model Higgs boson decaying to a charm quark-antiquark pair, H→cc[over ¯], produced in association with a leptonically decaying V (W or Z) boson is presented. The search is performed with proton-proton collisions at sqrt[s]=13  TeV collected by the CMS experiment, corresponding to an integrated luminosity of 138  fb^{-1}. Novel charm jet identification and analysis methods using machine learning techniques are employed. The analysis is validated by searching for Z→cc[over ¯] in VZ events, leading to its first observation at a hadron collider with a significance of 5.7 standard deviations. The observed (expected) upper limit on σ(VH)B(H→cc[over ¯]) is 0.94 (0.50_{-0.15}^{+0.22})pb at 95% confidence level (C.L.), corresponding to 14 (7.6_{-2.3}^{+3.4}) times the standard model prediction. For the Higgs-charm Yukawa coupling modifier, κ_{c}, the observed (expected) 95% C.L. interval is 1.1<|κ_{c}|<5.5 (|κ_{c}|<3.4), the most stringent constraint to date.