129 research outputs found
Aprepitant for cough in lung cancer: a randomised placebo-controlled trial and mechanistic insights
RATIONALE: Effective cough treatments are a significant unmet need in lung cancer patients. Aprepitant is a licensed treatment for nausea and vomiting, which blocks substance P activation of Neurokinin 1 (NK-1) receptors, a mechanism also implicated in cough. OBJECTIVE: To assess aprepitant in lung cancer patients with cough and evaluate mechanisms in vagal nerve tissue. METHODS: Randomised double-blind crossover trial of lung cancer patients with bothersome cough. They received three days of aprepitant or matched placebo; following a three day wash out, patients crossed to the alternative treatment. The primary endpoint was awake cough frequency measured at screening and day 3 of each treatment; secondary endpoints included patient-reported outcomes. In vitro, the depolarization of isolated guinea pig and human vagus nerve sections in grease gap recording chambers, indicative of sensory nerve activation, was measured to evaluate mechanism. MEASUREMENTS AND MAIN RESULTS: Twenty lung cancer patients enrolled, mean age 66years (±7.7), 60% female, 80% non-small cell cancer, 50% advanced stage and 55% WHO performance status 1. Cough frequency improved with aprepitant, reducing by 22.2%(95%CI 2.8-37.7%) over placebo whilst awake (p=0.03), 30.3%(95%CI 12.7-44.3) over 24hours (p=0.002) and 59.8%(95%CI 15.1-86.0) during sleep (p=0.081). Patient-reported outcomes all significantly improved. Substance P depolarised both guinea pig and human vagus nerve. Aprepitant significantly inhibited substance P induced depolarisation by 78% in guinea pig (p=0.0145) and 94% in human vagus (p=0.0145). DISCUSSION: Substance P activation of NK-1 receptors appears to be an important mechanism driving cough in lung cancer, and NK-1 antagonists show promise as anti-tussive therapies. Clinical trial registration available at www.http://www.isrctn.com/, ID: ISRCTN16200035
Circumstellar disks and planets. Science cases for next-generation optical/infrared long-baseline interferometers
We present a review of the interplay between the evolution of circumstellar
disks and the formation of planets, both from the perspective of theoretical
models and dedicated observations. Based on this, we identify and discuss
fundamental questions concerning the formation and evolution of circumstellar
disks and planets which can be addressed in the near future with optical and
infrared long-baseline interferometers. Furthermore, the importance of
complementary observations with long-baseline (sub)millimeter interferometers
and high-sensitivity infrared observatories is outlined.Comment: 83 pages; Accepted for publication in "Astronomy and Astrophysics
Review"; The final publication is available at http://www.springerlink.co
Allocating HIV Prevention Funds in the United States: Recommendations from an Optimization Model
The Centers for Disease Control and Prevention (CDC) had an annual budget of approximately $327 million to fund health departments and community-based organizations for core HIV testing and prevention programs domestically between 2001 and 2006. Annual HIV incidence has been relatively stable since the year 2000 [1] and was estimated at 48,600 cases in 2006 and 48,100 in 2009 [2]. Using estimates on HIV incidence, prevalence, prevention program costs and benefits, and current spending, we created an HIV resource allocation model that can generate a mathematically optimal allocation of the Division of HIV/AIDS Prevention’s extramural budget for HIV testing, and counseling and education programs. The model’s data inputs and methods were reviewed by subject matter experts internal and external to the CDC via an extensive validation process. The model projects the HIV epidemic for the United States under different allocation strategies under a fixed budget. Our objective is to support national HIV prevention planning efforts and inform the decision-making process for HIV resource allocation. Model results can be summarized into three main recommendations. First, more funds should be allocated to testing and these should further target men who have sex with men and injecting drug users. Second, counseling and education interventions ought to provide a greater focus on HIV positive persons who are aware of their status. And lastly, interventions should target those at high risk for transmitting or acquiring HIV, rather than lower-risk members of the general population. The main conclusions of the HIV resource allocation model have played a role in the introduction of new programs and provide valuable guidance to target resources and improve the impact of HIV prevention efforts in the United States
A 10 year case study on the changing determinants of University student satisfaction in the UK
Higher Education (HE), once the prerogative of a tiny elite, is now accessible to larger numbers of people around the world than ever before yet despite the fact that an understanding of student satisfaction has never been more important for today’s universities, the concept remains poorly understood. Here we use published data from the UK’s National Student Survey (NSS), representing data from 2.3 million full-time students collected from 2007 to 2016, as a case study of the benefits and limitations of measuring student satisfaction that might have applicability for other countries, particularly those that, like the UK, have experienced significant growth in student numbers. The analyses showed that the factor structure of the NSS remained generally stable and that the ability of the NSS to discriminate between different subjects at different universities actually improved over the ten-year sample period. The best predictors of overall satisfaction were 'Teaching Quality' and 'Organisation & Management', with 'Assessment & Feedback' having relatively weak predictive ability, despite the sector's tangible efforts to improve on this metric. The tripling of student fees in 2012 for English students (but not the rest of the UK) was used as a ‘natural experiment’ to investigate the sensitivity of student satisfaction ratings to the real economic costs of HE. The tuition fee increase had no identifiable negative effect, with student satisfaction steadily improving throughout the decade. Although the NSS was never designed to measure perceived value-for money, its insensitivity to major changes in the economic costs of HE to the individual suggest that the conventional concept of student satisfaction is incomplete. As such we propose that the concept of student satisfaction: (i) needs to be widened to take into account the broader economic benefits to the individual student by including measures of perceived value-for-money and (ii) should measure students’ level of satisfaction in the years post-graduation, by which time they may have a greater appreciation of the value of their degree in the workplace
HIV Epidemic Appraisals for Assisting in the Design of Effective Prevention Programmes: Shifting the Paradigm Back to Basics
To design HIV prevention programmes, it is critical to understand the temporal and geographic aspects of the local epidemic and to address the key behaviours that drive HIV transmission. Two methods have been developed to appraise HIV epidemics and guide prevention strategies. The numerical proxy method classifies epidemics based on current HIV prevalence thresholds. The Modes of Transmission (MOT) model estimates the distribution of incidence over one year among risk-groups. Both methods focus on the current state of an epidemic and provide short-term metrics which may not capture the epidemiologic drivers. Through a detailed analysis of country and sub-national data, we explore the limitations of the two traditional methods and propose an alternative approach.We compared outputs of the traditional methods in five countries for which results were published, and applied the numeric and MOT model to India and six districts within India. We discovered three limitations of the current methods for epidemic appraisal: (1) their results failed to identify the key behaviours that drive the epidemic; (2) they were difficult to apply to local epidemics with heterogeneity across district-level administrative units; and (3) the MOT model was highly sensitive to input parameters, many of which required extraction from non-regional sources. We developed an alternative decision-tree framework for HIV epidemic appraisals, based on a qualitative understanding of epidemiologic drivers, and demonstrated its applicability in India. The alternative framework offered a logical algorithm to characterize epidemics; it required minimal but key data.Traditional appraisals that utilize the distribution of prevalent and incident HIV infections in the short-term could misguide prevention priorities and potentially impede efforts to halt the trajectory of the HIV epidemic. An approach that characterizes local transmission dynamics provides a potentially more effective tool with which policy makers can design intervention programmes
Culling-Induced Changes in Badger (Meles meles) Behaviour, Social Organisation and the Epidemiology of Bovine Tuberculosis
In the UK, attempts since the 1970s to control the incidence of bovine tuberculosis (bTB) in cattle by culling a wildlife host, the European badger (Meles meles), have produced equivocal results. Culling-induced social perturbation of badger populations may lead to unexpected outcomes. We test predictions from the ‘perturbation hypothesis’, determining the impact of culling operations on badger populations, movement of surviving individuals and the influence on the epidemiology of bTB in badgers using data dervied from two study areas within the UK Government's Randomised Badger Culling Trial (RBCT). Culling operations did not remove all individuals from setts, with between 34–43% of badgers removed from targeted social groups. After culling, bTB prevalence increased in badger social groups neighbouring removals, particularly amongst cubs. Seventy individual adult badgers were fitted with radio-collars, yielding 8,311 locational fixes from both sites between November 2001 and December 2003. Home range areas of animals surviving within removed groups increased by 43.5% in response to culling. Overlap between summer ranges of individuals from Neighbouring social groups in the treatment population increased by 73.3% in response to culling. The movement rate of individuals between social groups was low, but increased after culling, in Removed and Neighbouring social groups. Increased bTB prevalence in Neighbouring groups was associated with badger movements both into and out of these groups, although none of the moving individuals themselves tested positive for bTB. Significant increases in both the frequency of individual badger movements between groups and the emergence of bTB were observed in response to culling. However, no direct evidence was found to link the two phenomena. We hypothesise that the social disruption caused by culling may not only increase direct contact and thus disease transmission between surviving badgers, but may also increase social stress within the surviving population, causing immunosuppression and enhancing the expression of disease
The Ciliogenic Transcription Factor RFX3 Regulates Early Midline Distribution of Guidepost Neurons Required for Corpus Callosum Development
The corpus callosum (CC) is the major commissure that bridges the cerebral hemispheres. Agenesis of the CC is associated with human ciliopathies, but the origin of this default is unclear. Regulatory Factor X3 (RFX3) is a transcription factor involved in the control of ciliogenesis, and Rfx3–deficient mice show several hallmarks of ciliopathies including left–right asymmetry defects and hydrocephalus. Here we show that Rfx3–deficient mice suffer from CC agenesis associated with a marked disorganisation of guidepost neurons required for axon pathfinding across the midline. Using transplantation assays, we demonstrate that abnormalities of the mutant midline region are primarily responsible for the CC malformation. Conditional genetic inactivation shows that RFX3 is not required in guidepost cells for proper CC formation, but is required before E12.5 for proper patterning of the cortical septal boundary and hence accurate distribution of guidepost neurons at later stages. We observe focused but consistent ectopic expression of Fibroblast growth factor 8 (Fgf8) at the rostro commissural plate associated with a reduced ratio of GLIoma-associated oncogene family zinc finger 3 (GLI3) repressor to activator forms. We demonstrate on brain explant cultures that ectopic FGF8 reproduces the guidepost neuronal defects observed in Rfx3 mutants. This study unravels a crucial role of RFX3 during early brain development by indirectly regulating GLI3 activity, which leads to FGF8 upregulation and ultimately to disturbed distribution of guidepost neurons required for CC morphogenesis. Hence, the RFX3 mutant mouse model brings novel understandings of the mechanisms that underlie CC agenesis in ciliopathies
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