41 research outputs found
ALMA detection of a tentative nearly edge-on rotating disk around the nearby AGB star R~Doradus
A spectral scan of the circumstellar environment of the asymptotic giant
branch (AGB) star R~Doradus was taken with ALMA in cycle 2 at frequencies
between 335 and 362 GHz and with a spatial resolution of 150
milliarcseconds. Many molecular lines show a spatial offset between the blue
and red shifted emission in the innermost regions of the wind. The
position-velocity diagrams of this feature, in combination with previous SPHERE
data and theoretical work point towards the presence of a compact
differentially rotating disk, orientated nearly edge-on. We model the SiO () emission with a disk model. We estimate the disk mass
and angular momentum to be Solar masses and . The latter presents an `angular momentum problem'
that may be solved by assuming that the disk is the result of wind-companion
interactions with a companion of at least 2.5 earth masses, located at 6 AU,
the tentatively determined location of the disk's inner rim. An isolated clump
of emission is detected to the south-east with a velocity that is high compared
to the previously determined terminal velocity of the wind. Its position and
mean velocity suggest that it may be associated with a companion planet,
located at the disk's inner rim.Comment: 11 pages, 7 Figure
Intraperitoneal aerosolization of albumin-stabilized paclitaxel nanoparticles (Abraxaneâ„¢) for peritoneal carcinomatosis : a phase I first-in-human study
Background: Nanoparticles hold considerable promise for aerosol-based intraperitoneal delivery in patients with carcinomatosis. Recently, results from preclinical and early clinical trials suggested that albumin-bound paclitaxel (ABP, Abraxane (TM)) may result in superior efficacy in the treatment of peritoneal metastases (PM) compared to the standard solvent-based paclitaxel formulation (Taxol (TM)). Here, we propose a phase I study of pressurized intraperitoneal aerosol chemotherapy (PIPAC) using ABP in patients with upper Gastrointestinal, breast, or ovarian cancer.
Methods: Eligible patients with advanced, biopsy-proven PM from ovarian, breast, gastric, hepatobiliary, or pancreatic origin will undergo three PIPAC treatments using ABP with a 4-week interval. The dose of ABP will be escalated from 35 to 140 mg/m(2) using a Bayesian approach until the maximally tolerated dose is determined. The primary end point is dose-limiting toxicity. Secondary analyses include surgical morbidity, non-access rate, pharmacokinetic and pharmacodynamic analyses, quality of life, and exploratory circulating biomarker analyses.
Discussion: ABP holds considerable promise for intraperitoneal aerosol delivery. The aim of this study is to determine the dose level for future randomized phase II trials using ABP in PIPAC therapy
Synergy between intraperitoneal aerosolization (PIPAC) and cancer nanomedicine : cisplatin-loaded polyarginine-hyaluronic acid nanocarriers efficiently eradicate peritoneal metastasis of advanced human ovarian cancer
Intra-abdominal dissemination of peritoneal nodules, a condition known as peritoneal carcinomatosis (PC), is typically diagnosed in ovarian cancer patients at the advanced stages. The current treatment of PC consists of perioperative systemic chemotherapy and cytoreductive surgery, followed by intra-abdominal flushing with solutions of chemotherapeutics such as cisplatin and oxaliplatin. In this study, we developed cisplatin-loaded polyarginine-hyaluronic acid nanoscale particles (Cis-pARG-HA NPs) with high colloidal stability, marked drug loading efficiency, unimpaired biological activity, and tumor-targeting ability. Injected Cis-pARG-HA NPs showed enhanced antitumor activity in a rat model of PC, compared to injection of the free cisplatin drug. The activity of Cis-pARG-HA NPs could even be further improved when administered by an intra-abdominal aerosol therapy, referred to as pressurized intraperitoneal aerosol chemotherapy (PIPAC). PIPAC is hypothesized to ensure a more homogeneous drug distribution together with a deeper drug penetration into peritoneal tumor nodules within the abdominal cavity. Using fluorescent pARG-HA NPs, this enhanced nanoparticle deposit on tumors could indeed be observed in regions opposite the aerosolization nozzle. Therefore, this study demonstrates that nanoparticles carrying chemotherapeutics can be synergistically combined with the PIPAC technique for IP therapy of disseminated advanced ovarian tumors, while this synergistic effect was not observed for the administration of free cisplatin
Gender differences in the use of cardiovascular interventions in HIV-positive persons; the D:A:D Study
Peer reviewe
Molecular Data Needs for Modelling AGB Stellar Winds and Other Molecular Environments
The modern era of highly sensitive telescopes is enabling the detection of more and more molecular species in various astronomical environments. Many of these are now being carefully examined for the first time. However, to move beyond detection to more detailed analysis such as radiative transfer modelling, certain molecular properties need to be properly measured and calculated. The importance of contributions from vibrationally excited states or collisional (de-)excitations can vary greatly, depending on the specific molecule and the environment being studied. Here, we discuss the present molecular data needs for detailed radiative transfer modelling of observations of molecular rotational transitions, primarily in the (sub-)millimetre and adjacent regimes, and with a focus on the stellar winds of AGB stars