The Sensitivity of HAWC to High-Mass Dark Matter Annihilations

The High Altitude Water Cherenkov (HAWC) observatory is a wide field-of-view detector sensitive to gamma rays of 100 GeV to a few hundred TeV. Located in central Mexico at 19 degrees North latitude and 4100 m above sea level, HAWC will observe gamma rays and cosmic rays with an array of water Cherenkov detectors. The full HAWC array is scheduled to be operational in Spring 2015. In this paper, we study the HAWC sensitivity to the gamma-ray signatures of high-mass (multi- TeV) dark matter annihilation. The HAWC observatory will be sensitive to diverse searches for dark matter annihilation, including annihilation from extended dark matter sources, the diffuse gamma-ray emission from dark matter annihilation, and gamma-ray emission from non-luminous dark matter subhalos. Here we consider the HAWC sensitivity to a subset of these sources, including dwarf galaxies, the M31 galaxy, the Virgo cluster, and the Galactic center. We simulate the HAWC response to gamma rays from these sources in several well-motivated dark matter annihilation channels. If no gamma-ray excess is observed, we show the limits HAWC can place on the dark matter cross-section from these sources. In particular, in the case of dark matter annihilation into gauge bosons, HAWC will be able to detect a narrow range of dark matter masses to cross-sections below thermal. HAWC should also be sensitive to non-thermal cross-sections for masses up to nearly 1000 TeV. The constraints placed by HAWC on the dark matter cross-section from known sources should be competitive with current limits in the mass range where HAWC has similar sensitivity. HAWC can additionally explore higher dark matter masses than are currently constrained.Comment: 15 pages, 4 figures, version to be published in PR

The Receptor Slamf1 on the Surface of Myeloid Lineage Cells Controls Susceptibility to Infection by Trypanosoma cruzi

Trypanosoma cruzi, the protozoan parasite responsible for Chagas' disease, causes severe myocarditis often resulting in death. Here, we report that Slamf1−/− mice, which lack the hematopoietic cell surface receptor Slamf1, are completely protected from an acute lethal parasite challenge. Cardiac damage was reduced in Slamf1−/− mice compared to wild type mice, infected with the same doses of parasites, as a result of a decrease of the number of parasites in the heart even the parasitemia was only marginally less. Both in vivo and in vitro experiments reveal that Slamf1-defIcient myeloid cells are impaired in their ability to replicate the parasite and show altered production of cytokines. Importantly, IFN-γ production in the heart of Slamf1 deficient mice was much lower than in the heart of wt mice even though the number of infiltrating dendritic cells, macrophages, CD4 and CD8 T lymphocytes were comparable. Administration of an anti-Slamf1 monoclonal antibody also reduced the number of parasites and IFN-γ in the heart. These observations not only explain the reduced susceptibility to in vivo infection by the parasite, but they also suggest human Slamf1 as a potential target for therapeutic target against T. cruzi infection

Analisis de las respuestas moleculares profundas alcanzadas por las multiples secuencias de tratamientos con ITKS en LMC. Estudio de largo seguimiento del registro español de LMC

Poster [PC-231] Introducción: Cinco inhibidores de tirosina cinasa (ITKs) están disponibles para el tratamiento de pacientes con leucemia mieloide crónica en fase crónica (LMC-FC). Analizamos las diferentes secuencias de ITKs utilizadas como terapia para la LMC-FC en un análisis a largo plazo en vida real. Métodos: En un análisis retrospectivo de cohortes, se incluyeron pacientes con LMC-FC tratados en la práctica clínica con diferentes ITKs en el Registro Español de LMC (RELMC) (17 hospitales de todo el país) entre 2000 y 2014. El objetivo principal del estudio fue describir la secuencia del tratamiento con ITKs en la práctica de la vida real y la última respuesta molecular profunda (DMR) (MR4, MR4.5 o transcrito indetectable) para cada esquema. Resultados: Nuestro análisis incluyó 862 pacientes con LMC en 1º FC tratados con ITKs en 1ª línea o después de interferón alfa. Datos demográficos demográficos: 517 H, 345 M, mediana de edad: 52 años (14-94a). Distribución del Índice Sokal (bajo 49% Inter 38% Alto 13%), Índice EURO (bajo 50% Inter 45% Alto 5%), Índice EUTOS (bajo 93% Alto 7%), Índice LT-EUTOS (bajo 68 % Inter 25% Alto 7%). Esquemas de tratamiento: la Tabla 1 resume todos los esquemas utilizados y la última respuesta molecular. Los pacientes se dividieron en 4 grupos según el tratamiento con ITKs. Grupo 1: solo tratados con Imatinib 394 p (45, 7%) Grupo 2: Imatinib y luego 2ºGITKs debido a intolerancia o fallo 170 p (19, 7%) (12 esquemas de tratamiento secuenciales diferentes con ITKs) Grupo 3: 2ºGITKs en 1ª línea 91 p (13 esquemas secuenciales) (10, 5%) Grupo 4: Interferón alfa y luego ITKs 207 p (24%) (9 esquemas secuenciales). La Figura 1 resume la evolución de diferentes tratamientos alrededor de los 14 años. Última respuesta molecular profunda: con una mediana de seguimiento de 82 meses (1-351 m) desde el diagnóstico, 77 m (1-311 m) desde el primer tratamiento y 70 m (1-191 m) desde el primer tratamiento con ITK. Las tasas de respuesta molecular profunda para cada grupo fueron (G1: DMR 65% MMR 13% No MMR 15%, G2: DMR 46% MMR 24% No MMR 17%, G3: DMR 62% MMR 13% No MMR 12%, G4: DMR 53% MMR 17% No MMR 18%). Supervivencia a largo plazo (SLP o SG): no se encontraron diferencias estadísticas entre los grupos de tratamiento, ya sea desde el diagnóstico, el primer tratamiento o el primer ITK. Alcanzar una respuesta profunda garantiza mejores resultados. Variables predictivas de respuesta: los índices SOKAL, EUTOS, EURO y LT-EUTOS continúan siendo útiles para predecir el resultado a largo plazo. Conclusiones: En el contexto de un registro multicéntrico basado en hospitales, el tratamiento con ITKs es muy variable, con un gran número de secuencias diferentes de ITKs. Con una mediana de seguimiento de 7 años la tasa de respuesta molecular profunda es aproximadamente del 60% en pacientes tratados con imatinib y que no necesitan cambio de ITKs, y en aquellos tratados en 1º línea con 2ºGITKs(a pesar de su corto seguimiento), pero parece menor en pacientes tratados con imatinib que necesitan cambiar a 2ºGITKs. Los resultados de supervivencia fueron similares para todos los grupos

Adjuvant dabrafenib and trametinib for patients with resected BRAF-mutated melanoma: DESCRIBE-AD real-world retrospective observational study

BRAF and MEK inhibitor, dabrafenib plus trametinib, adjuvant therapy is effective for high-risk resected melanoma patients with BRAF-V600 mutations. However, real-world evidence is limited. We aimed to determine the feasibility of this therapy in routine clinical practice. DESCRIBE-AD, a retrospective observational study, collected real-world data from 25 hospitals in Spain. Histologically confirmed and resected BRAF-mutated melanoma patients aged & GE;18 years who were previously treated with dabrafenib plus trametinib adjuvant therapy, were included. The primary objectives were treatment discontinuation rate and time to discontinuation. The secondary objectives included safety and efficacy. From October 2020 to March 2021, 65 patients were included. Dabrafenib and trametinib discontinuation rate due to treatment-related adverse events (TRAEs) of any grade was 9%. Other reasons for discontinuation included patients' decisions (6%), physician decisions (6%), unrelated adverse events (3%), disease progression (5%), and others (5%). The median time to treatment discontinuation was 9 months [95% confidence interval (CI), 5-11]. G3-4 TRAEs occurred in 21.5% of patients, the most common being pyrexia (3%), asthenia (3%), and diarrhoea (3%). Unscheduled hospitalisations and clinical tests occurred in 6 and 22% of patients, respectively. After 20-month median follow-up (95% CI, 18-22), 9% of patients had exitus due to disease progression, with a 12-month relapse-free survival and overall survival rates of 95.3% and 100%, respectively. Dabrafenib and trametinib adjuvant therapy proved effective for melanoma patients in a real-world setting, with a manageable toxicity profile. Toxicity frequencies were low leading to low incidence of unscheduled medical visits, tests, and treatment discontinuations

Cardiac-Oxidized Antigens Are Targets of Immune Recognition by Antibodies and Potential Molecular Determinants in Chagas Disease Pathogenesis

Trypanosoma cruzi elicits reactive oxygen species (ROS) of inflammatory and mitochondrial origin in infected hosts. In this study, we examined ROS-induced oxidative modifications in the heart and determined whether the resultant oxidized cardiac proteins are targets of immune response and of pathological significance in Chagas disease. Heart biopsies from chagasic mice, rats and human patients exhibited, when compared to those from normal controls, a substantial increase in protein 4-hydroxynonenal (4-HNE), malondialdehyde (MDA), carbonyl, and 3-nitrotyrosine (3-NT) adducts. To evaluate whether oxidized proteins gain antigenic properties, heart homogenates or isolated cardiomyocytes were oxidized in vitro and one- or two-dimensional gel electrophoresis (2D-GE)/Western blotting (WB) was performed to investigate the proteomic oxidative changes and recognition of oxidized proteins by sera antibodies in chagasic rodents (mice, rats) and human patients. Human cardiomyocytes exhibited LD50 sensitivity to 30 µM 4-HNE and 100 µM H2O2 at 6 h and 12 h, respectively. In vitro oxidation with 4-HNE or H2O2 resulted in a substantial increase in 4-HNE- and carbonyl-modified proteins that correlated with increased recognition of cardiac (cardiomyocytes) proteins by sera antibodies of chagasic rodents and human patients. 2D-GE/Western blotting followed by MALDI-TOF-MS/MS analysis to identify cardiac proteins that were oxidized and recognized by human chagasic sera yielded 82 unique proteins. We validated the 2D-GE results by enzyme-linked immunosorbent assay (ELISA) and WB and demonstrated that oxidation of recombinant titin enhanced its immunogenicity and recognition by sera antibodies from chagasic hosts (rats and humans). Treatment of infected rats with phenyl-α-tert-butyl nitrone (PBN, antioxidant) resulted in normalized immune detection of cardiac proteins associated with control of cardiac pathology and preservation of heart contractile function in chagasic rats. We conclude that ROS-induced, cardiac-oxidized antigens are targets of immune recognition by antibodies and molecular determinants for pathogenesis during Chagas disease

Measurement of the Lambda(b) cross section and the anti-Lambda(b) to Lambda(b) ratio with Lambda(b) to J/Psi Lambda decays in pp collisions at sqrt(s) = 7 TeV

The Lambda(b) differential production cross section and the cross section ratio anti-Lambda(b)/Lambda(b) are measured as functions of transverse momentum pt(Lambda(b)) and rapidity abs(y(Lambda(b))) in pp collisions at sqrt(s) = 7 TeV using data collected by the CMS experiment at the LHC. The measurements are based on Lambda(b) decays reconstructed in the exclusive final state J/Psi Lambda, with the subsequent decays J/Psi to an opposite-sign muon pair and Lambda to proton pion, using a data sample corresponding to an integrated luminosity of 1.9 inverse femtobarns. The product of the cross section times the branching ratio for Lambda(b) to J/Psi Lambda versus pt(Lambda(b)) falls faster than that of b mesons. The measured value of the cross section times the branching ratio for pt(Lambda(b)) > 10 GeV and abs(y(Lambda(b))) < 2.0 is 1.06 +/- 0.06 +/- 0.12 nb, and the integrated cross section ratio for anti-Lambda(b)/Lambda(b) is 1.02 +/- 0.07 +/- 0.09, where the uncertainties are statistical and systematic, respectively.Comment: Submitted to Physics Letters

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum