4,796 research outputs found
Biologically effective dose correlates with linear tumor volume changes after upfront single-fraction stereotactic radiosurgery for vestibular schwannomas.
Vestibular schwannomas (VSs) are benign, slow-growing tumors. Management options include observation, surgery, and radiation. In this retrospective trial, we aimed at evaluating whether biologically effective dose (BED) plays a role in tumor volume changes after single-fraction first intention stereotactic radiosurgery (SRS) for VS. We compiled a single-institution experience (n = 159, Lausanne University Hospital, Switzerland). The indication for SRS was decided after multidisciplinary discussion. Only cases with minimum 3 years follow-up were included. The Koos grading, a reliable method for tumor classification was used. Radiosurgery was performed using Gamma Knife (GK) and a uniform marginal prescription dose of 12 Gy. Mean BED was 66.3 Gy (standard deviation 3.8, range 54.1-73.9). The mean follow-up period was 5.1 years (standard deviation 1.7, range 3-9.2). The primary outcome was changes in 3D volumes after SRS as function of BED and of integral dose received by the VS. Random-effect linear regression model showed that tumor volume significantly and linearly decreased over time with higher BED (p < 0.0001). Changes in tumor volume were also significantly associated with age, sex, number of isocenters, gradient index, and Koos grade. However, the effect of BED on tumor volume change was moderated by time after SRS and Koos grade. Lower integral doses received by the VSs were inversely correlated with BED in relationship with tumor volume changes (p < 0.0001). Six (3.4%) patients needed further intervention. For patients having uniformly received the same marginal dose prescription, higher BED linearly and significantly correlated with tumor volume changes after SRS for VSs. BED could represent a potential new treatment paradigm for patients with benign tumors, such as VSs, for attaining a desired radiobiological effect. This could further increase the efficacy and decrease the toxicity of SRS not only in benign tumors but also in other SRS indications
Factors associated with polypharmacy and excessive polypharmacy in older people with Intellectual Disability differ from the general population; a cross-sectional observational nationwide study
Objectives: (1) To evaluate the prevalence of polypharmacy (5–9 medicines) and excessive polypharmacy (10+ medicines) and (2) to determine associated demographic and clinical characteristics in an ageing population with intellectual disabilities (IDs).
Design: Observational cross-sectional study.
Setting: Wave One (2009/2010) of the Intellectual Disability Supplement to the Irish Longitudinal Study on Ageing (IDS-TILDA).
Participants: A nationally representative sample of 753 persons with ID, aged between 41 and 90 years. Participants/proxy reported medicines ( prescription and over the counter) taken on a regular basis; medication data was available for 736 participants (98%).
Main outcome measures/interventions: Participants were divided into those with no polypharmacy (0–4 medicines), polypharmacy (5–9 medicines) and excessive polypharmacy (10+ medicines). Medication use patterns were analysed according to demographic variables and reported chronic conditions. A multinomial logistic regression model identified factors associated with polypharmacy (5–9 medicines) and excessive polypharmacy (≥10 medicines).
Results: Overall, 90% of participants reported use of medicines. Polypharmacy was observed in 31.5% of participants and excessive polypharmacy in 20.1%. Living in a residential institution, and reporting a mental health or neurological condition were strongly associated with polypharmacy and excessive polypharmacy after adjusting for confounders, but age or gender had no significant effect.
Conclusions: Polypharmacy was commonplace for older adults with ID and may be partly explained by the high prevalence of multimorbidity reported. Review of appropriateness of medication use is essential, as polypharmacy places ageing people with ID at risk of adverse effects
Factors associated with polypharmacy and excessive polypharmacy in older people with Intellectual Disability differ from the general population; a cross-sectional observational nationwide study
Objectives: (1) To evaluate the prevalence of polypharmacy (5–9 medicines) and excessive polypharmacy (10+ medicines) and (2) to determine associated demographic and clinical characteristics in an ageing population with intellectual disabilities (IDs).
Design: Observational cross-sectional study.
Setting: Wave One (2009/2010) of the Intellectual Disability Supplement to the Irish Longitudinal Study on Ageing (IDS-TILDA).
Participants: A nationally representative sample of 753 persons with ID, aged between 41 and 90 years. Participants/proxy reported medicines ( prescription and over the counter) taken on a regular basis; medication data was available for 736 participants (98%).
Main outcome measures/interventions: Participants were divided into those with no polypharmacy (0–4 medicines), polypharmacy (5–9 medicines) and excessive polypharmacy (10+ medicines). Medication use patterns were analysed according to demographic variables and reported chronic conditions. A multinomial logistic regression model identified factors associated with polypharmacy (5–9 medicines) and excessive polypharmacy (≥10 medicines).
Results: Overall, 90% of participants reported use of medicines. Polypharmacy was observed in 31.5% of participants and excessive polypharmacy in 20.1%. Living in a residential institution, and reporting a mental health or neurological condition were strongly associated with polypharmacy and excessive polypharmacy after adjusting for confounders, but age or gender had no significant effect.
Conclusions: Polypharmacy was commonplace for older adults with ID and may be partly explained by the high prevalence of multimorbidity reported. Review of appropriateness of medication use is essential, as polypharmacy places ageing people with ID at risk of adverse effects
Detection of Sharp Symmetric Features in the Circumbinary Disk Around AK Sco
The Search for Planets Orbiting Two Stars (SPOTS) survey aims to study the
formation and distribution of planets in binary systems by detecting and
characterizing circumbinary planets and their formation environments through
direct imaging. With the SPHERE Extreme Adaptive Optics instrument, a good
contrast can be achieved even at small (<300 mas) separations from bright
stars, which enables studies of planets and disks in a separation range that
was previously inaccessible. Here, we report the discovery of resolved
scattered light emission from the circumbinary disk around the well-studied
young double star AK Sco, at projected separations in the ~13--40 AU range. The
sharp morphology of the imaged feature is surprising, given the smooth
appearance of the disk in its spectral energy distribution. We show that the
observed morphology can be represented either as a highly eccentric ring around
AK Sco, or as two separate spiral arms in the disk, wound in opposite
directions. The relative merits of these interpretations are discussed, as well
as whether these features may have been caused by one or several circumbinary
planets interacting with the disk.Comment: 10 pages, 3 figures, accepted for publication in ApJ Letters. Minor
(proof-level) corrections implemented in this versio
The SPHERE data center: a reference for high contrast imaging processing
The objective of the SPHERE Data Center is to optimize the scientific return
of SPHERE at the VLT, by providing optimized reduction procedures, services to
users and publicly available reduced data. This paper describes our motivation,
the implementation of the service (partners, infrastructure and developments),
services, description of the on-line data, and future developments. The SPHERE
Data Center is operational and has already provided reduced data with a good
reactivity to many observers. The first public reduced data have been made
available in 2017. The SPHERE Data Center is gathering a strong expertise on
SPHERE data and is in a very good position to propose new reduced data in the
future, as well as improved reduction procedures.Comment: SF2A proceeding
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