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Role of topical tretinoin in melanoma and dysplastic nevi.
The retinoids have been investigated extensively as chemopreventive and therapeutic agents in a variety of neoplasms. They have been shown to inhibit the proliferation of transformed cell lines in vitro and transplanted tumors in vivo. In cultured murine melanoma cells, retinoids inhibit proliferation and induce differentiation. Human melanoma cell lines have shown a mixed response. The clinical experience with retinoids in melanoma has been limited. Previously we investigated the activity of topical B-all-trans-retinoic acid (Retin-A, vitamin A acid, retinoic acid, and tretinoin) against intracutaneous metastases from malignant melanoma. We saw complete remission of multiple lesions in one individual and regression of several lesions in a second patient. This experience led us to conduct the present pilot trial of topical tretinoin in dysplastic nevus syndrome. The latter is a precursor of malignant melanoma. We saw regression of some of the treated lesions to benign nevi showing minimal or no dysplasia. Thus topical tretinoin appears to possess some activity against melanoma and at least one of its precursor conditions. In view of these preliminary results, more extensive trials are warranted to better define the role of tretinoin in the chemoprevention of malignant melanoma in high-risk lesions
Reconstructing communities in cluster trials?
BACKGROUND: There is growing interest in the ethics of cluster trials, but no literature on the uncertainties in defining communities in relation to the scientific notion of the cluster in collaborative biomedical research. METHODS: The views of participants in a community-based cluster randomised trial (CRT) in Mumbai, India, were solicited regarding their understanding and views on community. We conducted two focus group discussions with local residents and 20 semi-structured interviews with different respondent groups. On average, ten participants took part in each focus group, most of them women aged 18-55. We conducted semi-structured interviews with ten residents (nine women and one man) lasting approximately an hour each and seven individuals (five men and two women) identified by residents as local leaders or decision-makers. In addition, we interviewed two Municipal Corporators (locally elected government officials involved in urban planning and development) and one representative of a political party located in a slum community. RESULTS: Residents' sense of community largely matched the scientific notion of the cluster, defined by the investigators as a geographic area, but their perceived needs were not entirely met by the trial. CONCLUSION: We examined whether the possibility of a conceptual mismatch between 'clusters' and 'communities' is likely to have methodological implications for a study or to lead to potential social disharmony because of the research interventions, arguing that it is important to take social factors into account as well as statistical efficiency when choosing the size and type of clusters and designing a trial. One method of informing such a design would be to use existing forums for community engagement to explore individuals' primary sense of community or social group and, where possible, to fit clusters around them. TRIAL REGISTRATION: ISRCTN Register: ISRCTN56183183 Clinical Trials Registry of India: CTRI/2012/09/003004
Homeless drug users' awareness and risk perception of peer "Take Home Naloxone" use – a qualitative study
BACKGROUND
Peer use of take home naloxone has the potential to reduce drug related deaths. There appears to be a paucity of research amongst homeless drug users on the topic. This study explores the acceptability and potential risk of peer use of naloxone amongst homeless drug users. From the findings the most feasible model for future treatment provision is suggested.
METHODS
In depth face-to-face interviews conducted in one primary care centre and two voluntary organisation centres providing services to homeless drug users in a large UK cosmopolitan city. Interviews recorded, transcribed and analysed thematically by framework techniques.
RESULTS
Homeless people recognise signs of a heroin overdose and many are prepared to take responsibility to give naloxone, providing prior training and support is provided. Previous reports of the theoretical potential for abuse and malicious use may have been overplayed.
CONCLUSION
There is insufficient evidence to recommend providing "over the counter" take home naloxone" to UK homeless injecting drug users. However a programme of peer use of take home naloxone amongst homeless drug users could be feasible providing prior training is provided. Peer education within a health promotion framework will optimise success as current professionally led health promotion initiatives are failing to have a positive impact amongst homeless drug users
A Value-Based Approach to Increase Breast Cancer Screening and Health-Directed Behaviors among American Indian Women
American Indian/Alaska Native (AI/AN) women have the lowest cancer-screening rate of any ethnic or racial group; AI/AN women in all regions are less likely than non-Hispanic white women to be diagnosed with localized breast cancer; and those AI/AN women presenting with breast cancer have the lowest 5-year survival rate compared to other ethnic groups. This study found that cultural beliefs are more of a factor in mammography screening behavior than other barriers such as access; and that a more holistic educational intervention designed by AI/AN women prompted individual intent and actions to seek mammograms among AI/AN women >40 and to change unhealthy eating and sedentary lifestyles
Marine ecosystem response to the Atlantic Multidecadal Oscillation.
Against the backdrop of warming of the Northern Hemisphere it has recently been acknowledged that North Atlantic temperature changes undergo considerable variability over multidecadal periods. The leading component of natural low-frequency temperature variability has been termed the Atlantic Multidecadal Oscillation (AMO). Presently, correlative studies on the biological impact of the AMO on marine ecosystems over the duration of a whole AMO cycle (∼60 years) is largely unknown due to the rarity of continuously sustained biological observations at the same time period. To test whether there is multidecadal cyclic behaviour in biological time-series in the North Atlantic we used one of the world's longest continuously sustained marine biological time-series in oceanic waters, long-term fisheries data and historical records over the last century and beyond. Our findings suggest that the AMO is far from a trivial presence against the backdrop of continued temperature warming in the North Atlantic and accounts for the second most important macro-trend in North Atlantic plankton records; responsible for habitat switching (abrupt ecosystem/regime shifts) over multidecadal scales and influences the fortunes of various fisheries over many centuries
A prospective study of decline in fat free mass and skeletal muscle strength in chronic obstructive pulmonary disease
BACKGROUND: Skeletal muscle depletion is an important complication of chronic obstructive pulmonary disease (COPD) but little prospective data exists about the rate at which it occurs and the factors that promote its development. We therefore prospectively investigated the impact of disease severity, exacerbation frequency and treatment with corticosteroids on change in body composition and maximum isometric quadriceps strength (QMVC) over one year. METHODS: 64 patients with stable COPD (FEV(1 )mean (SD) 35.8(18.4) %predicted) were recruited from clinic and studied on two occasions one year apart. Fat free mass was determined using bioelectrical impedance analysis and a disease specific regression equation. RESULTS: QMVC fell from 34.8(1.5) kg to 33.3(1.5) kg (p = 0.04). The decline in quadriceps strength was greatest in those with the highest strength at baseline (R -0.28 p = 0.02) and was not correlated with lung function, exacerbation frequency or steroid treatment. Decline in fat free mass was similarly higher in those with largest FFM at baseline (R = -0.31 p = 0.01) but was more strongly correlated with greater gas trapping (R = -0.4 p = 0.001). Patients with frequent exacerbations (>1 per year) (n = 36) experienced a greater decline in fat free mass compared to infrequent exacerbators (n = 28) -1.3(3.7)kg vs. +1.2(3.1)kg (p = 0.005), as did patients on maintenance oral steroids (n = 8) -2.8(3.3) kg vs. +0.2(3.5) kg (p = 0.024) whereas in those who stopped smoking (n = 7) fat free mass increased; +2.7(3.1) kg vs. -0.51(3.5) kg (p = 0.026). CONCLUSION: Decline in fat free mass in COPD is associated with worse lung function, continued cigarette consumption and frequent exacerbations. Factors predicting progression of quadriceps weakness could not be identified from the present cohort
SARS-CoV-2 viability on sports equipment is limited, and dependent on material composition
The control of the COVID-19 pandemic in the UK has necessitated restrictions on amateur and professional sports due to the perceived infection risk to competitors, via direct person to person transmission, or possibly via the surfaces of sports equipment. The sharing of sports equipment such as tennis balls was therefore banned by some sport’s governing bodies. We sought to investigate the potential of sporting equipment as transmission vectors of SARS-CoV-2. Ten different types of sporting equipment, including balls from common sports, were inoculated with 40 μl droplets containing clinically relevant concentrations of live SARS-CoV-2 virus. Materials were then swabbed at time points relevant to sports (1, 5, 15, 30, 90 min). The amount of live SARS-CoV-2 recovered at each time point was enumerated using viral plaque assays, and viral decay and half-life was estimated through fitting linear models to log transformed data from each material. At one minute, SARS-CoV-2 virus was recovered in only seven of the ten types of equipment with the low dose inoculum, one at five minutes and none at 15 min. Retrievable virus dropped significantly for all materials tested using the high dose inoculum with mean recovery of virus falling to 0.74% at 1 min, 0.39% at 15 min and 0.003% at 90 min. Viral recovery, predicted decay, and half-life varied between materials with porous surfaces limiting virus transmission. This study shows that there is an exponential reduction in SARS-CoV-2 recoverable from a range of sports equipment after a short time period, and virus is less transferrable from materials such as a tennis ball, red cricket ball and cricket glove. Given this rapid loss of viral load and the fact that transmission requires a significant inoculum to be transferred from equipment to the mucous membranes of another individual it seems unlikely that sports equipment is a major cause for transmission of SARS-CoV-2. These findings have important policy implications in the context of the pandemic and may promote other infection control measures in sports to reduce the risk of SARS-CoV-2 transmission and urge sports equipment manufacturers to identify surfaces that may or may not be likely to retain transferable virus
Androgen receptor gene amplification and protein expression in hormone refractory prostate cancer
This study examined androgen receptor (AR) gene amplification and protein expression in 102 matched paired hormone sensitive and resistant tumours from 51 patients. AR gene amplification and X chromosome copy number were assessed by fluorescent in situ hybridisation, and protein expression was assessed by immunohistochemistry. All tumours were stained for PSA protein expression. Significantly more tumours exhibited AR amplification following the development of hormone resistance (20%, 10 out of 49) compared to matched hormone-sensitive tumours from the same patient (2%, one out of 48) (P = 0.0085). The level of AR expression was significantly higher in hormone- resistant tumours compared to matched hormone-sensitive tumours from the same patient (130, interquartile range, 55-167 vs 94.5 interquartile range, 55-120, P = 0.019). AR expression levels in hormone-resistant tumours with and without AR amplification were not significantly different. However, an increase in AR expression was seen with the development of AR amplification in paired tumours. The rate of AR gene amplification and/or an increase in AR protein expression during androgen resistant is too low to wholly explain the development of androgen resistance. Alternative mechanisms for modulating the function of the AR, or other signalling pathways, must be considered as key factors in the development of hormone-resistant prostate
Comparing performance of primary care clinicians in the interpretation of SPIROmetry with or without Artificial Intelligence Decision support software (SPIRO-AID): a protocol for a randomised controlled trial.
INTRODUCTION: Spirometry is a point-of-care lung function test that helps support the diagnosis and monitoring of chronic lung disease. The quality and interpretation accuracy of spirometry is variable in primary care. This study aims to evaluate whether artificial intelligence (AI) decision support software improves the performance of primary care clinicians in the interpretation of spirometry, against reference standard (expert interpretation). METHODS AND ANALYSIS: A parallel, two-group, statistician-blinded, randomised controlled trial of primary care clinicians in the UK, who refer for, or interpret, spirometry. People with specialist training in respiratory medicine to consultant level were excluded. A minimum target of 228 primary care clinician participants will be randomised with a 1:1 allocation to assess fifty de-identified, real-world patient spirometry sessions through an online platform either with (intervention group) or without (control group) AI decision support software report. Outcomes will cover primary care clinicians' spirometry interpretation performance including measures of technical quality assessment, spirometry pattern recognition and diagnostic prediction, compared with reference standard. Clinicians' self-rated confidence in spirometry interpretation will also be evaluated. The primary outcome is the proportion of the 50 spirometry sessions where the participant's preferred diagnosis matches the reference diagnosis. Unpaired t-tests and analysis of covariance will be used to estimate the difference in primary outcome between intervention and control groups. ETHICS AND DISSEMINATION: This study has been reviewed and given favourable opinion by Health Research Authority Wales (reference: 22/HRA/5023). Results will be submitted for publication in peer-reviewed journals, presented at relevant national and international conferences, disseminated through social media, patient and public routes and directly shared with stakeholders. TRIAL REGISTRATION NUMBER: NCT05933694
The Emotional and Political Power of Images of Suffering: Discursive Psychology and the Study of Visual Rhetoric
Drawing on insights from discursive and rhetorical approaches in psychology, the chapter examines responses to the publication of the photographs of the body of Alan Kurdi, the three-year-old Syrian refugee who drowned off the coast of Turkey in 2015. The chapter considers how and why the images were constructed as inherently ‘moving’, and as possessing the power to elicit emotions, and affect the audience on a ‘visceral’ level. It also looks at how accounts of (and for) emotional reactions to the images were deployed rhetorically to manage accountability associated with viewing, and sharing, images of a dead child. Through the examination of the Kurdi images the chapter also considers the possibility of a psychologically-informed approach to visual rhetoric, one that offers a better understanding of how and why certain images (but not others) are constituted as topics of humanitarian concern, and a source of emotional and political investment
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