1,027 research outputs found

    The uptake of drugs by necrophagous insects

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    University of Technology, Sydney. Faculty of Science.Insects have been used for several decades around the world to assist forensic scientists and pathologists in determining the time elapsed since death, by analysing their growth. Whilst the rate of larval growth is primarily affected by temperature, entomologists soon discovered that the presence of certain drugs can also significantly accelerate or decelerate larval growth rates. It was from this research that scientists discovered the ability of fly larvae to accumulate drugs within their body and toxicologists became interested in the possibility of exploiting insects feeding upon the decaying tissues of a human body as alternative toxicological specimens. Theoretically, insects offered great potential over the 'traditional' specimens (blood, urine, organs), which are degraded by the decomposition process and become extremely difficult to analyse. Consequently research into the field of entomotoxicology began and soon divided the toxicological community. Some academics argued that their results from larval analysis displayed enormous variance and bore no relationship to cadaver concentrations whilst others maintained that under controlled study correlations between larval and body concentrations have been found. The primary objective of this research was to determine what effect a variety of variables common to cadaver ecology would have on larval drug uptake. While previous studies have employed traditional methods of analysis with GC-MS and HPLC, for these experiments a new method of analysis was devised with LC-MS-MS which offered vast improvements in processing time and adaptability. A suitable method for the preservation of larval samples for the purpose of drug analysis was also devised. Larvae samples were exposed to a range of amitriptyline concentrations and then killed and preserved either by freezing or storage in a 70% ethanol solution after a brief immersion in boiling water. The analysis of amitriptyline concentration in larval samples tested at various times over a 12 month period demonstrated that freezing was the superior method of larval storage for drug analysis. A number of experiments were then designed to determine the effect that variables such as temperature, larval activity, larval species, drug dose and the presence of multiple substances have on the larval uptake of drugs. These progressively relaxed the controls on the feeding environment so that each effect could be determined separately. Thus initial experiments compared larval uptake of amitriptyline in three constant temperatures. Next the impact of fluctuating temperature and larval species on the uptake of amitriptyline was determined. Finally larvae were exposed to amitriptyline and caffeine to determine the impact of a second substance (caffeine) on the larval uptake of the primary drug (amitriptyline). These experiments have conclusively shown that larval drug uptake is significantly affected by these variables. Decreasing temperature causes a significant decrease in the rate and level of larval drug uptake. Fluctuating temperature compared to constant temperature has a similar effect. When a second substance was introduced again the amitriptyline concentration in the larval samples dropped. Despite this, larval drug concentrations were found to correlate linearly with their foodstuff concentrations (i.e. as the drug concentrations in their food increased the drug concentrations in the larval also increased in linear proportions). However this was limited to larvae that were actively feeding. Insects (especially blowfly larvae) that associate with human remains can be a valuable resource in forensic toxicology. However the fact that drug concentrations are significantly affected by temperature and the nature of the drugs present means that these must be considered when attempting to estimate the original cadaver drug concentrations from the larval concentrations

    Choosing a Doctor: Does Presentation Format Affect the Way Consumers Use Health Care Performance Information?

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    © 2017, Springer International Publishing Switzerland. Background: Choosing a new health service provider can be difficult and is dependent on the type and clarity of the information available. This study examines if the presentation of service quality information affects the decisions of consumers choosing a general medical practice. Objectives: The aim was to examine the impact of presentation format on attribute level interpretation and relative importance. Methods: A discrete choice experiment eliciting preferences for a general medical practice was conducted using four different presentation formats for service quality attributes: (1) frequency and percentage with an icon array, (2) star ratings, (3) star ratings with a text benchmark, and (4) percentage alone. A total of 1208 respondents from an online panel were randomised to see two formats, answering nine choices for each, where one was a dominated choice. Logistic regression was used to assess the impact of presentation format on the probability of choosing a dominated alternative. A generalised multinomial logit model was used to estimate the relative importance of the attribute levels. Results: The probability of incorrectly choosing a dominated alternative was significantly higher when the quality information was presented as a percentage relative to a frequency with icon array, star rating or bench-marked star rating. Preferences for a practice did not differ significantly by presentation format, nor did the probability of finding the information difficult to understand. Conclusions: Quantitative health service quality information will be more useful to consumers if presented by combining the numerical information with a graphic, or using a star rating if appropriate for the context

    Embracing additive manufacture: implications for foot and ankle orthosis design

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    <p>Abstract</p> <p>Background</p> <p>The design of foot and ankle orthoses is currently limited by the methods used to fabricate the devices, particularly in terms of geometric freedom and potential to include innovative new features. Additive manufacturing (AM) technologies, where objects are constructed via a series of sub-millimetre layers of a substrate material, may present the opportunity to overcome these limitations and allow novel devices to be produced that are highly personalised for the individual, both in terms of fit and functionality.</p> <p>Two novel devices, a foot orthosis (FO) designed to include adjustable elements to relieve pressure at the metatarsal heads, and an ankle foot orthosis (AFO) designed to have adjustable stiffness levels in the sagittal plane, were developed and fabricated using AM. The devices were then tested on a healthy participant to determine if the intended biomechanical modes of action were achieved.</p> <p>Results</p> <p>The adjustable, pressure relieving FO was found to be able to significantly reduce pressure under the targeted metatarsal heads. The AFO was shown to have distinct effects on ankle kinematics which could be varied by adjusting the stiffness level of the device.</p> <p>Conclusions</p> <p>The results presented here demonstrate the potential design freedom made available by AM, and suggest that it may allow novel personalised orthotic devices to be produced which are beyond the current state of the art.</p

    Immediate Surgical Repositioning Following Intrusive Luxation: A Case Report and Review of the Literature

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    This report presents a case of severe intrusive luxation of mature maxillary lateral incisor in a 10-year-old boy. The intruded tooth was immediately repositioned (surgical extrusion) and splinted within 2 h following injury. Tetracycline therapy was initiated at the time of repositioning and maintained for 10 days. Pulp removal and calcium hydroxide treatment of the root canal was carried out after repositioning. Splint was removed 1 month later. Definitive root canal treatment with gutta percha was accomplished at the second month recall. Clinical and radiographic examination 28 months after the surgical extrusion revealed satisfactory apical and periodontal healing

    The challenges faced in the design, conduct and analysis of surgical randomised controlled trials

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    Randomised evaluations of surgical interventions are rare; some interventions have been widely adopted without rigorous evaluation. Unlike other medical areas, the randomised controlled trial (RCT) design has not become the default study design for the evaluation of surgical interventions. Surgical trials are difficult to successfully undertake and pose particular practical and methodological challenges. However, RCTs have played a role in the assessment of surgical innovations and there is scope and need for greater use. This article will consider the design, conduct and analysis of an RCT of a surgical intervention. The issues will be reviewed under three headings: the timing of the evaluation, defining the research question and trial design issues. Recommendations on the conduct of future surgical RCTs are made. Collaboration between research and surgical communities is needed to address the distinct issues raised by the assessmentof surgical interventions and enable the conduct of appropriate and well-designed trials.The Health Services Research Unit is funded by the Scottish Government Health DirectoratesPeer reviewedPublisher PD

    Translating shared decision-making into health care clinical practices: Proof of concepts

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    Background: There is considerable interest today in shared decision-making (SDM), defined as a decision-making process jointly shared by patients and their health care provider. However, the data show that SDM has not been broadly adopted yet. Consequently, the main goal of this proposal is to bring together the resources and the expertise needed to develop an interdisciplinary and international research team on the implementation of SDM in clinical practice using a theory-based dyadic perspective. Methods: Participants include researchers from Canada, US, UK, and Netherlands, representing medicine, nursing, psychology, community health and epidemiology. In order to develop a collaborative research network that takes advantage of the expertise of the team members, the following research activities are planned: 1) establish networking and on-going communication through internet-based forum, conference calls, and a bi-weekly e-bulletin; 2) hold a two-day workshop with two key experts (one in theoretical underpinnings of behavioral change, and a second in dyadic data analysis), and invite all investigators to present their views on the challenges related to the implementation of SDM in clinical practices; 3) conduct a secondary analyses of existing dyadic datasets to ensure that discussion among team members is grounded in empirical data; 4) build capacity with involvement of graduate students in the workshop and online forum; and 5) elaborate a position paper and an international multi-site study protocol. Discussion: This study protocol aims to inform researchers, educators, and clinicians interested in improving their understanding of effective strategies to implement shared decision-making in clinical practice using a theory-based dyadic perspective

    Evaluation of the current knowledge limitations in breast cancer research: a gap analysis

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    BACKGROUND A gap analysis was conducted to determine which areas of breast cancer research, if targeted by researchers and funding bodies, could produce the greatest impact on patients. METHODS Fifty-six Breast Cancer Campaign grant holders and prominent UK breast cancer researchers participated in a gap analysis of current breast cancer research. Before, during and following the meeting, groups in seven key research areas participated in cycles of presentation, literature review and discussion. Summary papers were prepared by each group and collated into this position paper highlighting the research gaps, with recommendations for action. RESULTS Gaps were identified in all seven themes. General barriers to progress were lack of financial and practical resources, and poor collaboration between disciplines. Critical gaps in each theme included: (1) genetics (knowledge of genetic changes, their effects and interactions); (2) initiation of breast cancer (how developmental signalling pathways cause ductal elongation and branching at the cellular level and influence stem cell dynamics, and how their disruption initiates tumour formation); (3) progression of breast cancer (deciphering the intracellular and extracellular regulators of early progression, tumour growth, angiogenesis and metastasis); (4) therapies and targets (understanding who develops advanced disease); (5) disease markers (incorporating intelligent trial design into all studies to ensure new treatments are tested in patient groups stratified using biomarkers); (6) prevention (strategies to prevent oestrogen-receptor negative tumours and the long-term effects of chemoprevention for oestrogen-receptor positive tumours); (7) psychosocial aspects of cancer (the use of appropriate psychosocial interventions, and the personal impact of all stages of the disease among patients from a range of ethnic and demographic backgrounds). CONCLUSION Through recommendations to address these gaps with future research, the long-term benefits to patients will include: better estimation of risk in families with breast cancer and strategies to reduce risk; better prediction of drug response and patient prognosis; improved tailoring of treatments to patient subgroups and development of new therapeutic approaches; earlier initiation of treatment; more effective use of resources for screening populations; and an enhanced experience for people with or at risk of breast cancer and their families. The challenge to funding bodies and researchers in all disciplines is to focus on these gaps and to drive advances in knowledge into improvements in patient care

    Surgery, with or without tamoxifen, vs tamoxifen alone for older women with operable breast cancer: Cochrane review

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    The published literature comparing surgery, with or without adjuvant endocrine therapy, with endocrine therapy alone in older women with operable breast cancer was systematically reviewed.The design used is Cochrane review. Randomised controlled trials retrieved from the Cochrane Breast Cancer Group Specialised Register on 29 June 2005. Eligible studies recruited women aged 70 years or over with operable breast cancer, fit for surgery under general anaesthia. The studies compared surgery (either mastectomy or wide local excision, with or without endocrine therapy) to endocrine therapy alone. Primary outcomes were overall survival (OS) and progression-free survival (PFS). Double data extraction and quality assessment were undertaken. Seven eligible trials were identified of which six had published time-to-event data. The quality of the allocation concealment was adequate in three studies and unclear in the remainder. In each case the endocrine therapy used was tamoxifen. When surgery alone was compared to endocrine therapy alone, there was no significant difference in OS (hazard ratio (HR) 0.98, 95% confidence interval (CI) 0.74–1.30, P=0.9), but a significant difference in PFS (HR 0.55, 95% CI 0.39–0.77, P=0.0006). When surgery with adjuvant endocrine therapy was compared to endocrine therapy alone, there was no significant difference in OS (HR 0.86, 95% CI 0.73–1.00, P=0.06), but a significant difference in PFS (HR 0.65 (95% CI 0.53–0.81, P=0.0001) for surgery plus endocrine therapy vs primary endocrine. The regimens have different side effect profiles with one study suggesting increased psychosocial morbidity at 3 months in the surgical arm, which resolves by 2 years. Primary endocrine therapy with tamoxifen is associated with inferior local disease control but non-inferior survival to surgery for breast cancer in older women. Trials are needed to evaluate appropriate selection criteria for its use in terms of patient co-morbidity and quality of life. Trials are needed to evaluate the clinical effectiveness of aromatase inhibitors as primary therapy for this population

    Role of A Novel Angiogenesis FKBPL-CD44 Pathway in Preeclampsia Risk Stratification and Mesenchymal Stem Cell Treatment.

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    ContextPreeclampsia is a leading cardiovascular complication in pregnancy lacking effective diagnostic and treatment strategies.ObjectiveTo investigate the diagnostic and therapeutic target potential of the angiogenesis proteins, FK506-binding protein like (FKBPL) and CD44.Design and interventionFKBPL and CD44 plasma concentration or placental expression were determined in women pre- or postdiagnosis of preeclampsia. Trophoblast and endothelial cell function was assessed following mesenchymal stem cell (MSC) treatment and in the context of FKBPL signaling.Settings and participantsHuman samples prediagnosis (15 and 20 weeks of gestation; n ≥ 57), or postdiagnosis (n = 18 for plasma; n = 4 for placenta) of preeclampsia were used to determine FKBPL and CD44 levels, compared to healthy controls. Trophoblast or endothelial cells were exposed to low/high oxygen, and treated with MSC-conditioned media (MSC-CM) or a FKBPL overexpression plasmid.Main outcome measuresPreeclampsia risk stratification and diagnostic potential of FKBPL and CD44 were investigated. MSC treatment effects and FKBPL-CD44 signaling in trophoblast and endothelial cells were assessed.ResultsThe CD44/FKBPL ratio was reduced in placenta and plasma following clinical diagnosis of preeclampsia. At 20 weeks of gestation, a high plasma CD44/FKBPL ratio was independently associated with the 2.3-fold increased risk of preeclampsia (odds ratio = 2.3, 95% confidence interval [CI] 1.03-5.23, P = 0.04). In combination with high mean arterial blood pressure (>82.5 mmHg), the risk further increased to 3.9-fold (95% CI 1.30-11.84, P = 0.016). Both hypoxia and MSC-based therapy inhibited FKBPL-CD44 signaling, enhancing cell angiogenesis.ConclusionsThe FKBPL-CD44 pathway appears to have a central role in the pathogenesis of preeclampsia, showing promising utilities for early diagnostic and therapeutic purposes

    Incidence and Prediction of Falls in Dementia: A Prospective Study in Older People

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    Falls are a major cause of morbidity and mortality in dementia, but there have been no prospective studies of risk factors for falling specific to this patient population, and no successful falls intervention/prevention trials. This prospective study aimed to identify modifiable risk factors for falling in older people with mild to moderate dementia.179 participants aged over 65 years were recruited from outpatient clinics in the UK (38 Alzheimer's disease (AD), 32 Vascular dementia (VAD), 30 Dementia with Lewy bodies (DLB), 40 Parkinson's disease with dementia (PDD), 39 healthy controls). A multifactorial assessment of baseline risk factors was performed and fall diaries were completed prospectively for 12 months. Dementia participants experienced nearly 8 times more incident falls (9118/1000 person-years) than controls (1023/1000 person-years; incidence density ratio: 7.58, 3.11-18.5). In dementia, significant univariate predictors of sustaining at least one fall included diagnosis of Lewy body disorder (proportional hazard ratio (HR) adjusted for age and sex: 3.33, 2.11-5.26), and history of falls in the preceding 12 months (HR: 2.52, 1.52-4.17). In multivariate analyses, significant potentially modifiable predictors were symptomatic orthostatic hypotension (HR: 2.13, 1.19-3.80), autonomic symptom score (HR per point 0-36: 1.055, 1.012-1.099), and Cornell depression score (HR per point 0-40: 1.053, 1.01-1.099). Higher levels of physical activity were protective (HR per point 0-9: 0.827, 0.716-0.956).The management of symptomatic orthostatic hypotension, autonomic symptoms and depression, and the encouragement of physical activity may provide the core elements for the most fruitful strategy to reduce falls in people with dementia. Randomised controlled trials to assess such a strategy are a priority
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