77 research outputs found
Treatment results for hypopharyngeal cancer by different treatment strategies and its secondary primary- an experience in Taiwan
<p>Abstract</p> <p>Purpose</p> <p>The aim of this study was to evaluate treatment results in our hypopharyngeal cancer patients.</p> <p>Patients and Methods</p> <p>A total of three hundred and ninety five hypopharyngeal cancer patients received radical treatment at our hospital; 96% were male. The majority were habitual smokers (88%), alcohol drinkers (73%) and/or betel quid chewers (51%). All patients received a CT scan or MRI for tumor staging before treatment. The stage distribution was stage I: 2 (0.5%); stage II: 22 (5.6%); stage III: 57 (14.4%) and stage IV: 314 (79.5%). Radical surgery was used first in 81 patients (20.5%), and the remaining patients (79.5%) received organ preservation-intended treatment (OPIT). In the OPIT group, 46 patients received radiotherapy alone, 156 patients received chemotherapy followed by radiotherapy (CT/RT) and 112 patients received concomitant chemo-radiotherapy (CCRT).</p> <p>Results</p> <p>The five-year overall survival rates for stages I/II, III and IV were 49.5%, 47.4% and 18.6%, respectively. There was no significant difference in overall and disease-specific survival rates between patients who received radical surgery first and those who received OPIT. In the OPIT group, CCRT tended to preserve the larynx better (p = 0.088), with three-year larynx preservation rates of 44.8% for CCRT and 27.2% for CT/RT. Thirty-seven patients developed a second malignancy, with an annual incidence of 4.6%.</p> <p>Conclusions</p> <p>There was no survival difference between OPIT and radical surgery in hypopharyngeal cancer patients at our hospital. CCRT may offer better laryngeal preservation than RT alone or CT/RT. However, prospective studies are still needed to confirm this finding. Additionally, second primary cancers are another important issue for hypopharyngeal cancer management.</p
Three Warm Jupiters around Solar-analog Stars Detected with TESS*
We report the discovery and characterization of three giant exoplanets orbiting solar-analog stars, detected by the TESS space mission and confirmed through ground-based photometry and radial velocity measurements taken at La Silla observatory with FEROS. TOI-2373 b is a warm Jupiter orbiting its host star every ∼13.3 days, and is one of the most massive known exoplanet with a precisely determined mass and radius around a star similar to the Sun, with an estimated mass of m _p = and a radius of r _p = . With a mean density of , TOI-2373 b is among the densest planets discovered so far. TOI-2416 b orbits its host star on a moderately eccentric orbit with a period of ∼8.3 days and an eccentricity of e = . TOI-2416 b is more massive than Jupiter with m _p = , however is significantly smaller with a radius of r _p = , leading to a high mean density of . TOI-2524 b is a warm Jupiter near the hot Jupiter transition region, orbiting its star every ∼7.2 days on a circular orbit. It is less massive than Jupiter with a mass of m _p = , and is consistent with an inflated radius of r _p = , leading to a low mean density of . The newly discovered exoplanets TOI-2373 b, TOI-2416 b, and TOI-2524 b have estimated equilibrium temperatures of K, K, and K, respectively, placing them in the sparsely populated transition zone between hot and warm Jupiters
TOI-858 B b: A hot Jupiter on a polar orbit in a loose binary
We report the discovery of a hot Jupiter on a 3.28-day orbit around a 1.08
M G0 star that is the secondary component in a loose binary system.
Based on follow-up radial velocity observations of TOI-858 B with CORALIE on
the Swiss 1.2 m telescope and CHIRON on the 1.5 m telescope at the Cerro Tololo
Inter-American Observatory (CTIO), we measured the planet mass to be M . Two transits were further observed with CORALIE to determine
the alignment of TOI-858 B b with respect to its host star. Analysis of the
Rossiter-McLaughlin signal from the planet shows that the sky-projected
obliquity is . Numerical simulations show that the
neighbour star TOI-858 A is too distant to have trapped the planet in a
Kozai-Lidov resonance, suggesting a different dynamical evolution or a
primordial origin to explain this misalignment. The 1.15 Msun primary F9 star
of the system (TYC 8501-01597-1, at ~11") was also observed with CORALIE
in order to provide upper limits for the presence of a planetary companion
orbiting that star.Comment: Accepted for publication in A&
A phase I study of the nitroimidazole hypoxia marker SR4554 using 19F magnetic resonance spectroscopy
SR4554 is a fluorine-containing 2-nitroimidazole, designed as a hypoxia marker detectable with 19F magnetic resonance spectroscopy (MRS). In an initial phase I study of SR4554, nausea/vomiting was found to be dose-limiting, and 1400 mg m−2 was established as MTD. Preliminary MRS studies demonstrated some evidence of 19F retention in tumour. In this study we investigated higher doses of SR4554 and intratumoral localisation of the 19F MRS signal. Patients had tumours 3 cm in diameter and 4 cm deep. Measurements were performed using 1H/19F surface coils and localised 19F MRS acquisition. SR4554 was administered at 1400 mg m−2, with subsequent increase to 2600 mg m−2 using prophylactic metoclopramide. Spectra were obtained immediately post infusion (MRS no. 1), at 16 h (MRS no. 2) and 20 h (MRS no. 3), based on the SR4554 half-life of 3.5 h determined from a previous study. 19Fluorine retention index (%) was defined as (MRS no. 2/MRS no. 1)*100. A total of 26 patients enrolled at: 1400 (n=16), 1800 (n=1), 2200 (n=1) and 2600 mg m−2 (n=8). SR4554 was well tolerated and toxicities were all grade 1; mean plasma elimination half-life was 3.7±0.9 h. SR4554 signal was seen on both unlocalised and localised MRS no. 1 in all patients. Localised 19F signals were detected at MRS no. 2 in 5 out of 9 patients and 4 out of 5 patients at MRS no. 3. The mean retention index in tumour was 13.6 (range 0.6-43.7) compared with 4.1 (range 0.6-7.3) for plasma samples taken at the same times (P=0.001) suggesting 19F retention in tumour and, therefore, the presence of hypoxia. We have demonstrated the feasibility of using 19F MRS with SR4554 as a potential method of detecting hypoxia. Certain patients showed evidence of 19F retention in tumour, supporting further development of this technique for detection of tumour hypoxia
The young mini-Neptune HD 207496b that is either a naked core or on the verge of becoming one
We report the discovery and characterisation of the transiting mini-Neptune
HD~207496~b (TOI-1099) as part of a large programme that aims to characterise
naked core planets. We obtained HARPS spectroscopic observations, one
ground-based transit, and high-resolution imaging which we combined with the
TESS photometry to confirm and characterise the TESS candidate and its host
star. The host star is an active early K dwarf with a mass of M, a radius of R, and a G magnitude
of 8. We found that the host star is young, Myr, allowing us to
gain insight into planetary evolution. We derived a planetary mass of ,\, a planetary radius of ,\ and
a planetary density of .
From internal structure modelling of the planet, we conclude that the planet
has either a water-rich envelope, a gas-rich envelope, or a mixture of both. We
have performed evaporation modelling of the planet. If we assume the planet has
a gas-rich envelope, we find that the planet has lost a significant fraction of
its envelope and its radius has shrunk. Furthermore, we estimate it will lose
all its remaining gaseous envelope in Gyr. Otherwise, the planet
could have already lost all its primordial gas and is now a bare ocean planet.
Further observations of its possible atmosphere and/or mass-loss rate would
allow us to distinguish between these two hypotheses. Such observations would
determine if the planet remains above the radius gap or if it will shrink and
be below the gap.Comment: 20 pages, 18 figures, 4 tables, A&A accepte
Hemolysis Is Associated with Low Reticulocyte Production Index and Predicts Blood Transfusion in Severe Malarial Anemia
Background: Falciparum Malaria, an infectious disease caused by the apicomplexan parasite Plasmodium falciparum, is among the leading causes of death and morbidity attributable to infectious diseases worldwide. In Gabon, Central Africa, one out of four inpatients have severe malarial anemia (SMA), a life-threatening complication if left untreated. Emerging drug resistant parasites might aggravate the situation. This case control study investigates biomarkers of enhanced hemolysis in hospitalized children with either SMA or mild malaria (MM). Methods and Findings: Ninety-one children were included, thereof 39 SMA patients. Strict inclusion criteria were chosen to exclude other causes of anemia. At diagnosis, erythrophagocytosis (a direct marker for extravascular hemolysis, EVH) was enhanced in SMA compared to MM patients (5.0 arbitrary units (AU) (interquartile range (IR): 2.2–9.6) vs. 2.1 AU (IR: 1.3–3.9), p<0.01). Furthermore, indirect markers for EVH, (i.e. serum neopterin levels, spleen size enlargement and monocyte pigment) were significantly increased in SMA patients. Markers for erythrocyte ageing, such as CD35 (complement receptor 1), CD55 (decay acceleration factor) and phosphatidylserine exposure (annexin-V-binding) were investigated by flow cytometry. In SMA patients, levels of CD35 and CD55 on the red blood cell surface were decreased and erythrocyte removal markers were increased when compared to MM or reconvalescent patients. Additionally, intravascular hemolysis (IVH) was quantified using several indirect markers (LDH, alpha-HBDH, haptoglobin and hemopexin), which all showed elevated IVH in SMA. The presence of both IVH and EVH predicted the need for blood transfusion during antimalarial treatment (odds ratio 61.5, 95% confidence interval (CI): 8.9–427). Interestingly, this subpopulation is characterized by a significantly lowered reticulocyte production index (RPI, p<0.05). Conclusions: Our results show the multifactorial pathophysiology of SMA, whereby EVH and IVH play a particularly important role. We propose a model where removal of infected and non-infected erythrocytes of all ages (including reticulocytes) by EVH and IVH is a main mechanism of SMA. Further studies are underway to investigate the mechanism and extent of reticulocyte removal to identify possible interventions to reduce the risk of SMA development
A low-eccentricity migration pathway for a 13-h-period Earth analogue in a four-planet system
It is commonly accepted that exoplanets with orbital periods shorter than one day, also known as ultra-short-period (USP) planets, formed further out within their natal protoplanetary disks before migrating to their current-day orbits via dynamical interactions. One of the most accepted theories suggests a violent scenario involving high-eccentricity migration followed by tidal circularization. Here we present the discovery of a four-planet system orbiting the bright (V = 10.5) K6 dwarf star TOI-500. The innermost planet is a transiting, Earth-sized USP planet with an orbital period of ~13 hours, a mass of 1.42 \ub1 0.18 M⊕, a radius of 1.166−0.058+0.061R⊕ and a mean density of 4.89−0.88+1.03gcm−3. Via Doppler spectroscopy, we discovered that the system hosts 3 outer planets on nearly circular orbits with periods of 6.6, 26.2 and 61.3 days and minimum masses of 5.03 \ub1 0.41 M⊕, 33.12 \ub1 0.88 M⊕ and 15.05−1.11+1.12M⊕, respectively. The presence of both a USP planet and a low-mass object on a 6.6-day orbit indicates that the architecture of this system can be explained via a scenario in which the planets started on low-eccentricity orbits then moved inwards through a quasi-static secular migration. Our numerical simulations show that this migration channel can bring TOI-500 b to its current location in 2 Gyr, starting from an initial orbit of 0.02 au. TOI-500 is the first four-planet system known to host a USP Earth analogue whose current architecture can be explained via a non-violent migration scenario
TOI-2257 b: A highly eccentric long-period sub-Neptune transiting a nearby M dwarf
N.S., R.W. and B.-O.D. acknowledge support from the Swiss National Science Foundation (PP00P2-163967 and PP00P2-190080). M.N.G. acknowledges support from MIT's Kavli Institute as a Juan Carlos Torres Fellow and from the European Space Agency (ESA) as an ESA Research Fellow. A.A.B., B.S.S.and I.A.S. acknowledge the support of the Ministry of Science and Higher Education of the Russian Federation under the grant 075-15-2020-780 (N13.1902.21.0039). L.D. is an F.R.S.-FNRS Postdoctoral Researcher. B.V.R. thanks the Heising-Simons Foundation for support. This publication benefits from the support of the French Community of Belgium in the context of the FRIA Doctoral Grant awarded to M.T. and E.J. acknowledges DGAPA for his postdoctoral fellowship. Y.G.M.C. acknowledges support from UNAM-DGAPA PAPIIT BG-101321. D.D. acknowledges support from the TESS Guest Investigator Program grant 80NSSC19K1727 and NASA Exoplanet Research Program grant 18-2XRP18_2-0136. We acknowledge support from the Centre for Space and Habitability (CSH) of the University of Bern. Part of this work received support from the National Centre for Competence in Research PlanetS, supported by the Swiss National Science Foundation (SNSF). Funding for the TESS mission is provided by NASA's Science Mission Directorate. We acknowledge the use of public TESS data from pipelines at the TESS Science Office and at the TESS Science Processing Operations Center. This research has made use of the Exoplanet Follow-up Observation Program website, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center for the production of the SPOC data products. This paper includes data collected by the TESS mission that are publicly available from the Mikulski Archive for Space Telescopes (MAST). This work is based upon observations carried out at the Observatorio Astronomico Nacional on the Sierra de San Pedro Martir (OAN-SPM), Baja California, Mexico. We warmly thank the entire technical staff of the Observatorio Astronomico Nacional at San Pedro Martir in Mexico for their unfailing support to SAINT-EX operations, namely: E. Cadena, T. Calvario, E. Colorado, F. Diaz, A. Franco, B. Garcia, C. Guerrero, G. Guisa, F. Guillen, A. Landa, L. Figueroa, B. Hernandez, J. Herrera, E. Lopez, E. Lugo, B. Martinez, G. Melgoza, F. Montalvo, J.M. Nunez, J.L. Ochoa, I. Plauchu, F. Quiroz, H. Riesgo, H. Serrano, T. Verdugo, I. Zavala. The research leading to these results has received funding from the European Research Council (ERC) under the FP/2007-2013 ERC grant agreement nffi 336480, and under the European Union's Horizon 2020 research and innovation programme (grants agreements nffi 679030 and 803193/BEBOP); from an Actions de Recherche Concertee (ARC) grant, financed by the Wallonia-Brussels Federation, from the Balzan Prize Foundation, from the BEL-SPO/BRAIN2.0 research program (PORTAL project), from the Science and Technology Facilities Council (STFC; grant nffi ST/S00193X/1), and from F.R.S-FNRS (Research Project ID T010920F). This work was also partially supported by a grant from the Simons Foundation (PI: Queloz, grant number 327127), as well as by the MERAC foundation (PI: Triaud). PI: Gillon is F.R.S.-FNRS Senior Research Associate.
TRAPPIST is funded by the Belgian Fund for Scientific Research (Fond National de la Recherche Scientifique, FNRS) under the grant PDR T.0120.21, with the participation of the Swiss National Science Fundation (SNF). M.G. and E.J. are F.R.S.-FNRS Senior Research Associate. This work makes use of observations from the LCOGT network. Part of the LCOGT telescope time was granted by NOIRLab through the Mid-Scale Innovations Program (MSIP). M.S.I.P. is funded by NSF. Some of the observations in the paper made use of the High-Resolution Imaging instrument(s) `Alopeke (and/or Zorro). `Alopeke (and/or Zorro) was funded by the NASA Exoplanet Exploration Program and built at the NASA Ames Research Center by Steve B. Howell, Nic Scott, Elliott P. Horch, and Emmett Quigley. Data were reduced using a software pipeline originally written by Elliott Horch and Mark Everett. `Alopeke (and/or Zorro) was mounted on the Gemini North (and/or South) telescope of the international Gemini Observatory, a program of NSF's OIR Lab, which is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation, on behalf of the Gemini partnership: the National Science Foundation (United States), National Research Council (Canada), Agencia Nacional de Investigacion y Desarrollo (Chile), Ministerio de Ciencia, Tecnologia e Innovacion (Argentina), Ministerio da Ciencia, Tecnologia, Inovacoes e Comunicacoes (Brazil), and Korea Astronomy and Space Science Institute (Republic of Korea). This research has made use of the NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. This research made use of exoplanet (Foreman-Mackey et al. 2021a,b) and its dependencies (Agol et al. 2020; Kumar et al. 2019; Astropy Collaboration 2013, 2018; Kipping 2013; Luger et al. 2019; Salvatier et al. 2016; Theano Development Team 2016). Additional use of software packages AstroImageJ (Collins et al. 2017) and TAPIR (Jensen 2013).Context. Thanks to the relative ease of finding and characterizing small planets around M-dwarf stars, these objects have become cornerstones in the field of exoplanet studies. The current paucity of planets in long-period orbits around M dwarfs makes such objects particularly compelling as they provide clues about the formation and evolution of these systems.
Aims. In this study we present the discovery of TOI-2257 b (TIC 198485881), a long-period (35 d) sub-Neptune orbiting an M3 star at 57.8 pc. Its transit depth is about 0.4%, large enough to be detected with medium-size, ground-based telescopes. The long transit duration suggests the planet is in a highly eccentric orbit (e similar to 0.5), which would make it the most eccentric planet known to be transiting an M-dwarf star.
Methods. We combined TESS and ground-based data obtained with the 1.0-meter SAINT-EX, 0.60-meter TRAPPIST-North, and 1.2-meter FLWO telescopes to find a planetary size of 2.2 R-circle plus and an orbital period of 35.19 days. In addition, we make use of archival data, high-resolution imaging, and vetting packages to support our planetary interpretation.
Results. With its long period and high eccentricity, TOI-2257 b falls into a novel slice of parameter space. Despite the planet's low equilibrium temperature (similar to 256 K), its host star's small size (R-* = 0.311 +/- 0.015) and relative infrared brightness (K-mag = 10.7) make it a suitable candidate for atmospheric exploration via transmission spectroscopy.Swiss National Science Foundation (SNSF)European Commission PP00P2-163967
PP00P2-190080MIT's Kavli InstituteEuropean Space Agency
European CommissionMinistry of Science and Higher Education of the Russian Federation 075-15-2020-780 (N13.1902.21.0039)Heising-Simons FoundationFrench Community of BelgiumDGAPAPrograma de Apoyo a Proyectos de Investigacion e Innovacion Tecnologica (PAPIIT)
Universidad Nacional Autonoma de Mexico BG-101321TESS Guest Investigator Program 80NSSC19K1727NASA Exoplanet Research Program 18-2XRP18_2-0136Centre for Space and Habitability (CSH) of the University of BernSwiss National Science Foundation (SNSF)European Research Council (ERC) 336480Actions de Recherche Concertee (ARC) grant - Wallonia-Brussels FederationUK Research & Innovation (UKRI)Science & Technology Facilities Council (STFC)Science and Technology Development Fund (STDF) ST/S00193X/1Fonds de la Recherche Scientifique - FNRS T010920FSimons Foundation 327127MERAC foundationFonds de la Recherche Scientifique - FNRS PDR T.0120.21Swiss National Science Foundation (SNSF)National Science Foundation (NSF)NASA Exoplanet Exploration Program
NASA's Science Mission DirectorateEuropean Research Council (ERC) 679030
803193/BEBOPBalzan Prize Foundation
BEL-SPO/BRAIN2.0 research program (PORTAL project
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