1,299 research outputs found
What is the psychological impact of mammographic screening on younger women with a family history of breast cancer? Findings from a prospective cohort study (PIMMS)
PURPOSE: Studies are underway to establish the clinical effectiveness of annual mammographic screening in women younger than 50 years with a family history of breast cancer. This study investigated both the positive and negative psychological effects of screening on these women. PATIENTS AND METHODS: Women who received an immediate all-clear result after mammography (n = 1,174) and women who were recalled for additional tests before receiving an all-clear result (false positive; n = 112) completed questionnaires: 1 month before mammography, and 1 and 6 months after receiving final results. The questionnaires included measures of cancer worry, psychological consequences, and perceived benefits of breast screening. RESULTS: Women who received an immediate all-clear result experienced a decrease in cancer worry and negative psychological consequences immediately after the result, whereas women who were recalled for additional tests did not. By 6 months this cancer-specific distress had reduced significantly in both groups. Changes in levels of distress were significantly different between the two groups, but in absolute terms the differences were not large. Recalled women reported significantly greater positive psychological consequences of screening immediately after the result, and were also more positive about the benefits of screening compared with women who received an immediate all-clear result. CONCLUSION: For women receiving an immediate all-clear result, participating in annual mammographic screening is psychologically beneficial. Furthermore, women who are recalled for additional tests do not appear to be harmed by screening: these women's positive views about mammography suggest that they view any distress caused by recall as an acceptable part of screening
Trimetric Imaging of the Martian Ionosphere Using a CubeSat Constellation
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143020/1/6.2017-5252.pd
Mammographic screening for young women with a family history of breast cancer: knowledge and views of those at risk
Although the effectiveness of mammography for women under the age of 50 years with a family history of breast cancer (FHBC) has not yet been proven, annual screening is being offered to these women to manage breast cancer risk. This study investigates women's awareness and interpretation of their familial risk and knowledge and views about mammographic screening. A total of 2231 women from 21 familial/breast/genetics centres who were assessed as moderate risk (17–30% lifetime risk) or high risk (>30% lifetime risk) completed a questionnaire before their mammographic screening appointment. Most women (70%) believed they were likely, very likely or definitely going to develop breast cancer in their lifetime. Almost all women (97%) understood that the purpose of mammographic screening was to allow the early detection of breast cancer. However, 20% believed that a normal mammogram result meant there was definitely no breast cancer present, and only 4% understood that screening has not been proven to save lives in women under the age of 50 years. Women held positive views on mammography but did not appear to be well informed about the potential disadvantages. These findings suggest that further attention should be paid to improving information provision to women with an FHBC being offered routine screening
Pathological complete response after neoadjuvant chemotherapy is an independent predictive factor irrespective of simplified breast cancer intrinsic subtypes: a landmark and two-step approach analyses from the EORTC 10994/BIG 1-00 phase III trial
The present analysis, carried out in the context of a randomized phase III trial, confirms superior outcomes for breast cancer patients for whom chemotherapy induces pathological complete response (pCR) after adjusting for other important prognostic factors. In contrast, when tumours do not achieve pCR, patients have a higher risk of relapse. This effect is observed in all intrinsic subtypes and justifies the current interest in post-neoadjuvant trial
The Martian Photoelectron Boundary as Seen by MAVEN
Photoelectron peaks in the 20â 30Â eV energy range are commonly observed in the planetary atmospheres, produced by the intense photoionization from solar 30.4Â nm photons. At Mars, these photoelectrons are known to escape the planet down its tail, making them tracers for the atmospheric escape. Furthermore, their presence or absence allow to define the soâ called photoelectron boundary (PEB), which separates the photoelectron dominated ionosphere from the external environment. We provide here a detailed statistical analysis of the location and properties of the PEB based on the Mars Atmosphere and Volatile EvolutioN (MAVEN) electron and magnetic field data obtained from September 2014 to May 2016 (including 1696 PEB crossings). The PEB appears as mostly sensitive to the solar wind dynamic and crustal fields pressures. Its variable altitude thus leads to a variable wake cross section for escape (up to â ¼+50%), which is important for deriving escape rates. The PEB is not always sharp and is characterized on average by the following: a magnetic field topology typical for the end of magnetic pileup region above it, more fieldâ aligned fluxes above than below, and a clear change of the altitude slopes of both electron fluxes and total density (that appears different from the ionopause). The PEB thus appears as a transition region between two plasma and fields configurations determined by the draping topology of the interplanetary magnetic field around Mars and much influenced by the crustal field sources below, whose dynamics also impacts the estimated escape rate of ionospheric plasma.Key PointsWe determined the influence of the main driving parameters on the altitude of the photoelectron boundary (PEB)We identified clear plasma and magnetic field characteristics of the PEB and discuss its nature with respect to the ionopauseWe show how the PEB dynamics modifies the tail cross section used for estimating the photoelectrons (and associated ions) escape ratePeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/139944/1/jgra53813_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/139944/2/jgra53813.pd
The read-across hypothesis and environmental risk assessment of pharmaceuticals
This article is made available through the Brunel Open Access Publishing Fund. Copyright © 2013 American Chemical Society.Pharmaceuticals in the environment have received increased attention over the past decade, as they are ubiquitous in rivers and waterways. Concentrations are in sub-ng to low μg/L, well below acute toxic levels, but there are uncertainties regarding the effects of chronic exposures and there is a need to prioritise which pharmaceuticals may be of concern. The read-across hypothesis stipulates that a drug will have an effect in non-target organisms only if the molecular targets such as receptors and enzymes have been conserved, resulting in a (specific) pharmacological effect only if plasma concentrations are similar to human therapeutic concentrations. If this holds true for different classes of pharmaceuticals, it should be possible to predict the potential environmental impact from information obtained during the drug development process. This paper critically reviews the evidence for read-across, and finds that few studies include plasma concentrations and mode of action based effects. Thus, despite a large number of apparently relevant papers and a general acceptance of the hypothesis, there is an absence of documented evidence. There is a need for large-scale studies to generate robust data for testing the read-across hypothesis and developing predictive models, the only feasible approach to protecting the environment.BBSRC Industrial Partnership Award BB/
I00646X/1 and BBSRC Industrial CASE Partnership Studentship
BB/I53257X/1 with AstraZeneca Safety Health and
Environment Research Programme
Dynamic liquefaction of shear zones in intact loess during simulated earthquake loading
The 2010-2011 Canterbury earthquake sequence in New Zealand exposed loess-mantled slopes in the area to very high levels of seismic excitation (locally measured as >2 g). Few loess slopes showed permanent local downslope deformation, and most of these showed only limited accumulated displacement. A series of innovative dynamic back pressured shear-box tests were undertaken on intact and remoulded loess samples collected from one of the recently active slopes replicating field conditions under different simplified horizontal seismic excitations. During each test, the strength reduction and excess pore water pressures generated were measured as the sample failed. Test results suggest that although dynamic liquefaction could have occurred, a key factor was likely to have been that the loess was largely unsaturated at the times of the large earthquake events. The failure of intact loess samples in the tests was complex and variable due to the highly variable geotechnical characteristics of the material. Some loess samples failed rapidly as a result of dynamic liquefaction as seismic excitation generated an increase in pore-water pressure, triggering rapid loss of strength and thus of shear resistance. Following initial failure, pore pressure dissipated with continued seismic excitation and the sample consolidated, resulting in partial shear-strength recovery. Once excess pore-water pressures had dissipated, deformation continued in a critical effective stress state with no further change in volume. Remoulded and weaker samples, however, did not liquefy, and instead immediately reduced in volume with an accompanying slower and more sustained increase in pore pressure as the sample consolidated. Thereafter excess pressures dissipated and deformation continued at a critical state. The complex behaviour explained why, despite exceptionally strong ground shaking, there was only limited displacement and lack of run-out: dynamic liquefaction was unlikely to occur in the freely draining slopes. Dynamic liquefaction however remained a plausible mechanism to explain loess failure in some of the low-angle toe slopes, where a permanent water table was present in the loess
Mechanisms Involved in Nicotinic Acetylcholine Receptor-Induced Neurotransmitter Release from Sympathetic Nerve Terminals in the Mouse Vas Deferens
Prejunctional nicotinic acetylcholine receptors (nAChRs) amplify postganglionic sympathetic neurotransmission, and there are indications that intraterminal Ca2+ stores might be involved. However, the mechanisms by which nAChR activation stimulates neurotransmitter release at such junctions is unknown. Rapid local delivery (picospritzing) of the nAChR agonist epibatidine was combined with intracellular sharp microelectrode recording to monitor spontaneous and field-stimulation-evoked neurotransmitter release from sympathetic nerve terminals in the mouse isolated vas deferens. Locally applied epibatidine (1 µM) produced ‘epibatidine-induced depolarisations’ (EIDs) that were similar in shape to spontaneous excitatory junction potentials (SEJPs) and were abolished by nonselective nAChR antagonists and the purinergic desensitizing agonist α,β-methylene ATP. The amplitude distribution of EIDs was only slightly shifted towards lower amplitudes by the selective α7 nAChR antagonists α-bungarotoxin and methyllcaconitine, the voltage-gated Na+ channel blocker tetrodotoxin or by blocking voltage-gated Ca2+ channels with Cd2+. Lowering the extracellular Ca2+ concentration reduced the frequency of EIDs by 69%, but more surprisingly, the Ca2+-induced Ca2+ release blocker ryanodine greatly decreased the amplitude (by 41%) and the frequency of EIDs by 36%. Ryanodine had no effect on electrically-evoked neurotransmitter release, paired-pulse facilitation, SEJP frequency, SEJP amplitude or SEJP amplitude distribution. These results show that activation of non-α7 nAChRs on sympathetic postganglionic nerve terminals induces high-amplitude junctional potentials that are argued to represent multipacketed neurotransmitter release synchronized by intraterminal Ca2+-induced Ca2+ release, triggered by Ca2+ influx directly through the nAChR. This nAChR-induced neurotransmitter release can be targeted pharmacologically without affecting spontaneous or electrically-evoked neurotransmitter release
- …