195 research outputs found
A randomised trial of robotic and open prostatectomy in men with localised prostate cancer
Background: Prostate cancer is the most common male cancer in the Western world however there is ongoing debate about the optimal treatment strategy for localised disease. While surgery remains the most commonly received treatment for localised disease in Australia more recently a robotic approach has emerged as an alternative to open and laparoscopic surgery. However, high level data is not yet available to support this as a superior approach or to guide treatment decision making between the alternatives. This paper presents the design of a randomised trial of Robotic and Open Prostatectomy for men newly diagnosed with localised prostate cancer that seeks to answer this question.Methods/design: 200 men per treatment arm (400 men in total) are being recruited after diagnosis and before treatment through a major public hospital outpatient clinic and randomised to 1) Robotic Prostatectomy or 2) Open Prostatectomy. All robotic prostatectomies are being performed by one surgeon and all open prostatectomies are being performed by one other surgeon. Outcomes are being measured pre-operatively and at 6 weeks and 3, 6, 12 and 24 months post-surgery. Oncological outcomes are being related to positive surgical margins, biochemical recurrence +/- the need for further treatment. Non-oncological outcome measures include: pain, physical and mental functioning, fatigue, summary (preference-based utility scores) and domain-specific QoL (urinary incontinence, bowel function and erectile function), cancer specific distress, psychological distress, decision-related distress and time to return to usual activities. Cost modelling of each approach, as well as full economic appraisal, is also being undertaken.Discussion: The study will provide recommendations about the relative benefits of Robotic and Open Prostatectomy to support informed patient decision making about treatment for localised prostate cancer; and to assist in treatment services planning for this patient group.Trial registration: ACTRN12611000661976
Recycled gabbro signature in hotspot magmas unveiled by plume–ridge interactions
Lavas erupted within plate interiors above upwelling mantle
plumes have chemical signatures that are distinct from midocean
ridge lavas. When a plume interacts with a mid-ocean
ridge, the compositions of both their lavas changes, but there
is no consensus as to how this interaction occurs1–3. For the
past 15 Myr, the Pacific–Antarctic mid-ocean ridge has been
approaching the Foundation hotspot4 and erupted lavas have
formed seamounts. Here we analyse the noble gas isotope
and trace element signature of lava samples collected from
the seamounts. We find that both intraplate and on-axis
lavas have noble gas isotope signatures consistent with the
contribution from a primitive plume source. In contrast, nearaxis
lavas show no primitive noble gas isotope signatures, but
are enriched in strontium and lead, indicative of subducted
former oceanic lower crust melting within the plume source5–7.
We propose that, in a near-ridge setting, primitive, plumesourced
magmas formed deep in the plume are preferentially
channelled to and erupted at the ridge-axis. The remaining
residue continues to rise and melt, forming the near-axis
seamounts. With the deep melts removed, the geochemical
signature of subduction contained within the residue becomes
apparent. Lavas with strontium and lead enrichments are found
worldwide where plumes meet mid-ocean ridges6–8, suggesting
that subducted lower crust is an important but previously
unrecognised plume component
The role of pyroxenite in basalt genesis: Melt-PX, a melting parameterization for mantle pyroxenites between 0.9 and 5GPa
Geochemical and isotopic data suggest that the source regions of oceanic basalts may contain
pyroxenite in addition to peridotite. In order to incorporate the wide range of compositions and melting
behaviors of pyroxenites into mantle melting models, we have developed a new parameterization, Melt-PX,
which predicts near-solidus temperatures and extents of melting as a function of temperature and pressure
for mantle pyroxenites. We used 183 high-pressure experiments (25 compositions; 0.9–5 GPa; 1150–1675°C)
to constrain a model of melt fraction versus temperature from 5% melting up to the disappearance of
clinopyroxene for pyroxenites as a function of pressure, temperature, and bulk composition. When applied to
the global set of experimental data, our model reproduces the experimental F values with a standard error of
estimate of 13% absolute; temperatures at which the pyroxenite is 5% molten are reproduced with a
standard error of estimate of 30°C over a temperature range of ~500°C and a pressure range of ~4 GPa. In
conjunction with parameterizations of peridotite melting, Melt-PX can be used to model the partial melting
of multilithologic mantle sources—including the effects of varying the composition and the modal
proportion of pyroxenite in such source regions. Examples of such applications include calculations of
isentropic decompression melting of a mixed peridotite + pyroxenite mantle; these show that although the
potential temperature of the upwelling mantle plays an important role in defining the extent of magma
production, the composition and mass fraction of the pyroxenite also exert strong controls
Hunger Modulates the Responses to Gustatory Stimuli of Single Neurons in the Caudolateral Orbitofrontal Cortex of the Macaque Monkey
Out of Mind, Out of Sight: Language Affects Perceptual Vividness in Memory
We examined whether language affects the strength of a visual representation in memory. Participants studied a picture, read a story about the depicted object, and then selected out of two pictures the one whose transparency level most resembled that of the previously presented picture. The stories contained two linguistic manipulations that have been demonstrated to affect concept availability in memory, i.e., object presence and goal-relevance. The results show that described absence of an object caused people to select the most transparent picture more often than described presence of the object. This effect was not moderated by goal-relevance, suggesting that our paradigm tapped into the perceptual quality of representations rather than, for example, their linguistic availability. We discuss the implications of these findings within a framework of grounded cognition
Reliability of clinical tests to evaluate nerve function and mechanosensitivity of the upper limb peripheral nervous system
BACKGROUND: Clinical tests to assess peripheral nerve disorders can be classified into two categories: tests for afferent/efferent nerve function such as nerve conduction (bedside neurological examination) and tests for increased mechanosensitivity (e.g. upper limb neurodynamic tests (ULNTs) and nerve palpation). Reliability reports of nerve palpation and the interpretation of neurodynamic tests are scarce. This study therefore investigated the intertester reliability of nerve palpation and ULNTs. ULNTs were interpreted based on symptom reproduction and structural differentiation. To put the reliability of these tests in perspective, a comparison with the reliability of clinical tests for nerve function was made.
METHODS: Two experienced clinicians examined 31 patients with unilateral arm and/or neck pain. The examination included clinical tests for nerve function (sensory testing, reflexes and manual muscle testing (MMT)) and mechanosensitivity (ULNTs and palpation of the median, radial and ulnar nerve). Kappa statistics were calculated to evaluate intertester reliability. A meta-analysis determined an overall kappa for the domains with multiple kappa values (MMT, ULNT, palpation). We then compared the difference in reliability between the tests of mechanosensitivity and nerve function using a one-sample t-test.
RESULTS: We observed moderate to substantial reliability for the tests for afferent/efferent nerve function (sensory testing: kappa = 0.53; MMT: kappa = 0.68; no kappa was calculated for reflexes due to a lack of variation). Tests to investigate mechanosensitivity demonstrated moderate reliability (ULNT: kappa = 0.45; palpation: kappa = 0.59). When compared statistically, there was no difference in reliability for tests for nerve function and mechanosensitivity (p = 0.06).
CONCLUSION: This study demonstrates that clinical tests which evaluate increased nerve mechanosensitivity and afferent/efferent nerve function have comparable moderate to substantial reliability. To further investigate the clinometric properties of these tests, more studies are needed to evaluate their validity
Revealing Repton: bringing landscape to life at Sheringham Park
The year 2012 marked 200 years since Humphry Repton (1752–1818) produced his design for Sheringham Park in north Norfolk, bound as one of his Red Books. On paper, Repton is England’s best-known and most influential landscape gardener. On the ground, his work is much harder to identify, focused as it was on light touches that equated more to landscape makeover than the landscape making of his predecessor Lancelot “Capability” Brown. This paper documents and evaluates a project that celebrated this bicentenary through a temporary exhibition within the visitor centre of Sheringham Park, whilst also making reference to the commemoration of his work in other places and on paper. In attempting to reveal Repton at Sheringham, we explore the context of the 1812 commission and the longer landscape history of the site, as well as the different methods of representing Repton on site that are open to site owners and managers
A trial assessing N-3 as treatment for injury-induced cachexia (ATLANTIC trial): does a moderate dose fish oil intervention improve outcomes in older adults recovering from hip fracture?
<p>Abstract</p> <p>Background</p> <p>Proximal femoral fractures are associated with increased morbidity and mortality. Pre-existing malnutrition and weight loss amongst this patient group is of primary concern, with conventional nutrition support being largely ineffective. The inflammatory response post proximal femoral fracture surgery and the subsequent risk of cachexia may explain the inability of conventional high energy high protein management to produce an anabolic response amongst these patients. Omega-3 fatty acids derived from fish oils have been extensively studied for their anti-inflammatory benefits. Due to their anti-inflammatory properties, the benefit of fish oil combined with individualized nutrition support amongst proximal femoral fracture patients post surgery is an attractive potential therapeutic strategy. The aim of the ATLANTIC trial is to assess the potential benefits of an anti-inflammatory dose of fish oil within the context of a 12 week individualised nutrition program, commencing seven days post proximal femoral fracture surgery.</p> <p>Methods/Design</p> <p>This randomized controlled, double blinded trial, will recruit 150 community dwelling elderly patients aged ≥65 years, within seven days of surgery for proximal femoral fracture. Participants will be randomly allocated to receive either a 12 week individualized nutrition support program complemented with 20 ml/day anti-inflammatory dose fish oil (~3.6 g eicosapentaenoic acid, ~2.4 g docosahexanoic acid; intervention), or, a 12 week individualized nutrition support program complemented with 20 ml/day low dose fish oil (~0.36 g eicosapentaenoic acid, ~0.24 g docosahexanoic acid; control).</p> <p>Discussion</p> <p>The ATLANTIC trial is the first of its kind to provide fish oil combined with individualized nutrition therapy as an intervention to address the inflammatory response experienced post proximal femoral fracture surgery amongst elderly patients. The final outcomes of this trial will assist clinicians in the development of effective and alternative treatment methods post proximal femoral fracture surgery which may ultimately result in a reduction in systemic inflammation, loss of weight and lean muscle and improvements in nutritional status, mobility, independence and quality of life among elderly patients.</p> <p>Trial Registration</p> <p>ACTRN12609000241235</p
Fish oil administration in older adults: is there potential for adverse events? A systematic review of the literature
ackground: Omega-3 (n-3) fatty acid supplementation is becoming increasingly popular. However given its
antithrombotic properties the potential for severe adverse events (SAE) such as bleeding has safety implications,
particularly in an older adult population. A systematic review of randomized control trials (RCT) was conducted to
explore the potential for SAE and non-severe adverse events (non-SAE) associated with n-3 supplementation in
older adults.
Methods: A comprehensive search strategy using Medline and a variety of other electronic sources was conducted.
Studies investigating the oral administration of n-3 fish oil containing eicosapentaenoic acid (EPA), docosahexaenoic
acid (DHA) or both against a placebo were sourced. The primary outcome of interest included reported SAE
associated with n-3 supplementation. Chi-square analyses were conducted on the pooled aggregate of AEs.
Results: Of the 398 citations initially retrieved, a total of 10 studies involving 994 older adults aged ≥60 years were
included in the review. Daily fish oil doses ranged from 0.03 g to 1.86 g EPA and/or DHA with study durations
ranging from 6 to 52 weeks. No SAE were reported and there were no significant differences in the total AE rate
between groups (n-3 intervention group: 53/540; 9.8%; placebo group: 28/454; 6.2%; p= 0.07). Non-SAE relating to
gastrointestinal (GI) disturbances were the most commonly reported however there was no significant increase in
the proportion of GI disturbances reported in participants randomized to the n-3 intervention (n-3 intervention
group: 42/540 (7.8%); placebo group: 24/454 (5.3%); p= 0.18).
Conclusions: The potential for AEs appear mild-moderate at worst and are unlikely to be of clinical significance. The
use of n-3 fatty acids and the potential for SAE should however be further researched to investigate whether this
evidence is consistent at higher doses and in other populations. These results also highlight that well-documented data
outlining the potential for SAE following n-3 supplementation are limited nor adequately reported to draw definitive
conclusions concerning the safety associated with n-3 supplementation. A more rigorous and systematic approach for
monitoring and recording AE data in clinical settings that involve n-3 supplementation is required.The authors would like to acknowledge funding
provided for the ongoing ATLANTIC randomized controlled trial supported
by the National Health and Medical Research Council (NHMRC), Australia
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