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Search Results: 1 - 10 of 4413 matches for " Linda Rogers "
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Beyond the limits of clinical governance? The case of mental health in English primary care
Linda Gask, Anne Rogers, Stephen Campbell, Rod Sheaff
BMC Health Services Research , 2008, DOI: 10.1186/1472-6963-8-63
Abstract: Framework analysis, based on the Normalisation Process Model (NPM), of attempts over a five year period to develop clinical governance for primary mental health services in Primary Care Trusts (PCTs). The data come from a longitudinal qualitative multiple case-study approach in a purposive sample of 12 PCTs, chosen to reflect a maximum variety of organisational contexts for mental health care provision.The constant change within the English NHS provided a difficult context in which to attempt to implement 'clinical governance' or, indeed, to reconstruct primary mental health care. In the absence of clear evidence or direct guidance about what 'primary mental health care' should be, and a lack of actors with the power or skills to set about realising it, the actors in 'clinical governance' had little shared knowledge or understanding of their role in improving the quality of mental health care. There was a lack of ownership of 'mental health' as an integral, normalised part of primary care.Despite some achievements in regard to monitoring and standardisation of prescribing practice, mental health care in primary care seems to have so far largely eluded the gaze of 'clinical governance'. Clinical governance in English primary mental health care has not yet become normalised. We make some policy recommendations which we consider would assist in the process normalisation and suggest other contexts to which our findings might apply.One specific approach in the international 'quest for quality' in health care has been a standardization of practices in medicine. It began early in the twentieth century, but gathered speed with the emerging discourse of 'Evidence-Based Medicine' in the 1990's [1]. Most attention has been given to the development and operationalisation of practice and clinical guidelines, which assemble evidence from scientific research into particular recommendations for health practitioners [2]. Less attention has been given to the organisational as opposed
Ageing Increases Vulnerability to Aβ42 Toxicity in Drosophila
Iain Rogers, Fiona Kerr, Pedro Martinez, John Hardy, Simon Lovestone, Linda Partridge
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0040569
Abstract: Age is the major risk factor for many neurodegenerative diseases, including Alzheimer's Disease (AD), for reasons that are not clear. The association could indicate that the duration or degree of exposure to toxic proteins is important for pathology, or that age itself increases susceptibility to protein toxicity. Using an inducible Drosophila model of AD, we investigated these possibilities by varying the expression of an Aβ42 transgene in neurons at different adult ages and measuring the effects on Aβ42 levels and associated pathological phenotypes. Acute induction of Arctic Aβ42 in young adult flies resulted in rapid expression and clearance of mRNA and soluble Arctic Aβ42 protein, but in irreversible expression of insoluble Arctic Aβ42 peptide. Arctic Aβ42 peptide levels accumulated with longer durations of induction, and this led to a dose-dependent reduction in negative geotaxis and lifespan. For a standardised level of mRNA expression, older flies had higher levels of Arctic Aβ42 peptide and associated toxicity, and this correlated with an age-dependent reduction in proteasome activity. Equalising Aβ42 protein at different ages shortened lifespan in correlation with the duration of exposure to the peptide, suggesting that Aβ42 expression accumulates damage over time. However, the relative reduction in lifespan compared to controls was greater in flies first exposed to the peptide at older ages, suggesting that ageing itself also increases susceptibility to Aβ42 toxicity. Indeed older flies were more vulnerable to chronic Aβ42 toxicity even with a much lower lifetime exposure to the peptide. Finally, the persistence of insoluble Aβ42 in both young and old induced flies suggests that aggregated forms of the peptide cause toxicity in later life. Our results suggest that reduced protein turnover, increased duration of exposure and increased vulnerability to protein toxicity at later ages in combination could explain the late age-of-onset of neurodegenerative phenotypes.
Facilitation of Task Performance and Removal of the Effects of Sleep Deprivation by an Ampakine (CX717) in Nonhuman Primates
Linda J. Porrino,James B. Daunais,Gary A. Rogers,Robert E. Hampson,Sam A. Deadwyler
PLOS Biology , 2012, DOI: 10.1371/journal.pbio.0030299
Abstract: The deleterious effects of prolonged sleep deprivation on behavior and cognition are a concern in modern society. Persons at risk for impaired performance and health-related issues resulting from prolonged sleep loss would benefit from agents capable of reducing these detrimental effects at the time they are sleep deprived. Agents capable of improving cognition by enhancing brain activity under normal circumstances may also have the potential to reduce the harmful or unwanted effects of sleep deprivation. The significant prevalence of excitatory α-amino-3-hydroxy-5-methyl-4-isoxazolepr?opionicacid (AMPA) glutamatergic receptors in the brain provides a basis for implementing a class of drugs that could act to alter or remove the effects of sleep deprivation. The ampakine CX717 (Cortex Pharmaceuticals), a positive allosteric modulator of AMPA receptors, was tested for its ability to enhance performance of a cognitive, delayed match-to-sample task under normal circumstances in well-trained monkeys, as well as alleviate the detrimental effects of 30–36 h of sleep deprivation. CX717 produced a dose-dependent enhancement of task performance under normal alert testing conditions. Concomitant measures of regional cerebral metabolic rates for glucose (CMRglc) during the task, utilizing positron emission tomography, revealed increased activity in prefrontal cortex, dorsal striatum, and medial temporal lobe (including hippocampus) that was significantly enhanced over normal alert conditions following administration of CX717. A single night of sleep deprivation produced severe impairments in performance in the same monkeys, accompanied by significant alterations in task-related CMRglc in these same brain regions. However, CX717 administered to sleep-deprived monkeys produced a striking removal of the behavioral impairment and returned performance to above-normal levels even though animals were sleep deprived. Consistent with this recovery, CMRglc in all but one brain region affected by sleep deprivation was also returned to the normal alert pattern by the drug. The ampakine CX717, in addition to enhancing cognitive performance under normal alert conditions, also proved effective in alleviating impairment of performance due to sleep deprivation. Therefore, the ability to activate specific brain regions under normal alert conditions and alter the deleterious effects of sleep deprivation on activity in those same regions indicate a potential role for ampakines in sustaining performance under these types of adverse conditions.
Facilitation of task performance and removal of the effects of sleep deprivation by an ampakine (CX717) in nonhuman primates.
Porrino Linda J,Daunais James B,Rogers Gary A,Hampson Robert E
PLOS Biology , 2005,
Abstract: The deleterious effects of prolonged sleep deprivation on behavior and cognition are a concern in modern society. Persons at risk for impaired performance and health-related issues resulting from prolonged sleep loss would benefit from agents capable of reducing these detrimental effects at the time they are sleep deprived. Agents capable of improving cognition by enhancing brain activity under normal circumstances may also have the potential to reduce the harmful or unwanted effects of sleep deprivation. The significant prevalence of excitatory alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamatergic receptors in the brain provides a basis for implementing a class of drugs that could act to alter or remove the effects of sleep deprivation. The ampakine CX717 (Cortex Pharmaceuticals), a positive allosteric modulator of AMPA receptors, was tested for its ability to enhance performance of a cognitive, delayed match-to-sample task under normal circumstances in well-trained monkeys, as well as alleviate the detrimental effects of 30-36 h of sleep deprivation. CX717 produced a dose-dependent enhancement of task performance under normal alert testing conditions. Concomitant measures of regional cerebral metabolic rates for glucose (CMRglc) during the task, utilizing positron emission tomography, revealed increased activity in prefrontal cortex, dorsal striatum, and medial temporal lobe (including hippocampus) that was significantly enhanced over normal alert conditions following administration of CX717. A single night of sleep deprivation produced severe impairments in performance in the same monkeys, accompanied by significant alterations in task-related CMRglc in these same brain regions. However, CX717 administered to sleep-deprived monkeys produced a striking removal of the behavioral impairment and returned performance to above-normal levels even though animals were sleep deprived. Consistent with this recovery, CMRglc in all but one brain region affected by sleep deprivation was also returned to the normal alert pattern by the drug. The ampakine CX717, in addition to enhancing cognitive performance under normal alert conditions, also proved effective in alleviating impairment of performance due to sleep deprivation. Therefore, the ability to activate specific brain regions under normal alert conditions and alter the deleterious effects of sleep deprivation on activity in those same regions indicate a potential role for ampakines in sustaining performance under these types of adverse conditions.
Facilitation of Task Performance and Removal of the Effects of Sleep Deprivation by an Ampakine (CX717) in Nonhuman Primates
Linda J Porrino,James B Daunais,Gary A Rogers,Robert E Hampson,Sam A Deadwyler
PLOS Biology , 2005, DOI: 10.1371/journal.pbio.0030299
Abstract: The deleterious effects of prolonged sleep deprivation on behavior and cognition are a concern in modern society. Persons at risk for impaired performance and health-related issues resulting from prolonged sleep loss would benefit from agents capable of reducing these detrimental effects at the time they are sleep deprived. Agents capable of improving cognition by enhancing brain activity under normal circumstances may also have the potential to reduce the harmful or unwanted effects of sleep deprivation. The significant prevalence of excitatory α-amino-3-hydroxy-5-methyl-4-isoxazolepr?opionicacid (AMPA) glutamatergic receptors in the brain provides a basis for implementing a class of drugs that could act to alter or remove the effects of sleep deprivation. The ampakine CX717 (Cortex Pharmaceuticals), a positive allosteric modulator of AMPA receptors, was tested for its ability to enhance performance of a cognitive, delayed match-to-sample task under normal circumstances in well-trained monkeys, as well as alleviate the detrimental effects of 30–36 h of sleep deprivation. CX717 produced a dose-dependent enhancement of task performance under normal alert testing conditions. Concomitant measures of regional cerebral metabolic rates for glucose (CMRglc) during the task, utilizing positron emission tomography, revealed increased activity in prefrontal cortex, dorsal striatum, and medial temporal lobe (including hippocampus) that was significantly enhanced over normal alert conditions following administration of CX717. A single night of sleep deprivation produced severe impairments in performance in the same monkeys, accompanied by significant alterations in task-related CMRglc in these same brain regions. However, CX717 administered to sleep-deprived monkeys produced a striking removal of the behavioral impairment and returned performance to above-normal levels even though animals were sleep deprived. Consistent with this recovery, CMRglc in all but one brain region affected by sleep deprivation was also returned to the normal alert pattern by the drug. The ampakine CX717, in addition to enhancing cognitive performance under normal alert conditions, also proved effective in alleviating impairment of performance due to sleep deprivation. Therefore, the ability to activate specific brain regions under normal alert conditions and alter the deleterious effects of sleep deprivation on activity in those same regions indicate a potential role for ampakines in sustaining performance under these types of adverse conditions.
A Two-Step Growth Curve: Approach to the von Bertalanffy and Gompertz Equations  [PDF]
Laura Rogers-Bennett, Donald W. Rogers
Advances in Pure Mathematics (APM) , 2016, DOI: 10.4236/apm.2016.65023
Abstract: Many curves have been proposed and debated to model individual growth of marine invertebrates. Broadly, they fall into two classes, first order (e.g. von Bertalanffy) and sigmoidal (e.g. Gompertz). We provide an innovative approach which demonstrates that the growth curves are not mutually exclusive but that either may arise from a simple three-stage growth model \"\" with two steps (k1 and k2) depending on the ratio of the growth parameters \"\". The new approach predicts sigmoidal growth when \"\" is close to 1, but if either growth from stage A to stage B or B to C is fast relative to the other, the slower of the two steps becomes the growth limiting step and the model reduces to first order growth. The resulting curves indicate that there is a substantial difference in the estimated size at time t during the period of active growth. This novel two-step rate model generates a growth surface that allows for changes in the rate parameters over time as reflected in the new parameter n(t) = k1(t) -?k2(t). The added degree of freedom brings about individual growth trajectories across the growth surface that is not easily mapped using conventional growth modeling techniques. This two (or more) stage growth model yields a growth surface that allows for a wide range of growth trajectories, accommodating staged growth, growth lags, as well as indeterminate growth and can help resolve debates as to which growth curves should be used to model animal growth. This flexibility can improve estimates of growth parameters used in population models influencing model outcomes and ultimately management decisions.=
Application of the Asthma Phenotype Algorithm from the Severe Asthma Research Program to an Urban Population
Paru Patrawalla, Angeliki Kazeros, Linda Rogers, Yongzhao Shao, Mengling Liu, Maria-Elena Fernandez-Beros, Shulian Shang, Joan Reibman
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0044540
Abstract: Rationale Identification and characterization of asthma phenotypes are challenging due to disease complexity and heterogeneity. The Severe Asthma Research Program (SARP) used unsupervised cluster analysis to define 5 phenotypically distinct asthma clusters that they replicated using 3 variables in a simplified algorithm. We evaluated whether this simplified SARP algorithm could be used in a separate and diverse urban asthma population to recreate these 5 phenotypic clusters. Methods The SARP simplified algorithm was applied to adults with asthma recruited to the New York University/Bellevue Asthma Registry (NYUBAR) to classify patients into five groups. The clinical phenotypes were summarized and compared. Results Asthma subjects in NYUBAR (n = 471) were predominantly women (70%) and Hispanic (57%), which were demographically different from the SARP population. The clinical phenotypes of the five groups generated by the simplified SARP algorithm were distinct across groups and distributed similarly to those described for the SARP population. Groups 1 and 2 (6 and 63%, respectively) had predominantly childhood onset atopic asthma. Groups 4 and 5 (20%) were older, with the longest duration of asthma, increased symptoms and exacerbations. Group 4 subjects were the most atopic and had the highest peripheral eosinophils. Group 3 (10%) had the least atopy, but included older obese women with adult-onset asthma, and increased exacerbations. Conclusions Application of the simplified SARP algorithm to the NYUBAR yielded groups that were phenotypically distinct and useful to characterize disease heterogeneity. Differences across NYUBAR groups support phenotypic variation and support the use of the simplified SARP algorithm for classification of asthma phenotypes in future prospective studies to investigate treatment and outcome differences between these distinct groups. Trial Registration Clinicaltrials.gov NCT00212537
Developing guided self-help for depression using the Medical Research Council complex interventions framework: a description of the modelling phase and results of an exploratory randomised controlled trial
Karina Lovell, Peter Bower, David Richards, Michael Barkham, Bonnie Sibbald, Chris Roberts, Linda Davies, Anne Rogers, Judith Gellatly, Sue Hennessy
BMC Psychiatry , 2008, DOI: 10.1186/1471-244x-8-91
Abstract: A guided self-help intervention was developed following a modelling phase which involved a systematic review, meta synthesis and a consensus process. The intervention was then tested in an exploratory randomised controlled trial by examining (a) fidelity using analysis of taped guided self-help sessions (b) acceptability to patients and professionals through qualitative interviews (c) effectiveness through estimation of the intervention effect size.Fifty eight patients were recruited to the exploratory trial. Seven professionals and nine patients were interviewed, and 22 tapes of sessions analysed for fidelity. Generally, fidelity to the intervention protocol was high, and the professionals delivered the majority of the specific components (with the exception of the use of feedback). Acceptability to both professionals and patients was also high. The effect size of the intervention on outcomes was small, and in line with previous analyses showing the modest effect of guided self-help in primary care. However, the sample size was small and confidence intervals around the effectiveness estimate were wide.The general principles of the modelling phase adopted in this study are designed to draw on a range of evidence, potentially providing an intervention that is evidence-based, patient-centred and acceptable to professionals. However, the pilot outcome data did not suggest that the intervention developed was particularly effective. The advantages and disadvantages of the general methods used in the modelling phase are discussed, and possible reasons for the failure to demonstrate a larger effect in this particular case are outlined.Depression is a significant cause of personal distress, social disability and economic consequences for patients, families and wider society [1]. Cognitive behaviour therapy (CBT) is a crucial treatment for depression [2], but access to CBT is characterised by long waiting lists [3]. The adoption of a 'stepped care' system has been proposed t
Delivering the WISE (Whole Systems Informing Self-Management Engagement) training package in primary care: learning from formative evaluation
Anne Kennedy, Carolyn Chew-Graham, Thomas Blakeman, Andrew Bowen, Caroline Gardner, Joanne Protheroe, Anne Rogers, Linda Gask
Implementation Science , 2010, DOI: 10.1186/1748-5908-5-7
Abstract: Normalisation Process Theory provided a framework for development of the intervention. Practices were recruited from an inner city Primary Care Trust in NW England. All practice staff were expected to attend two afternoon training sessions. The training sessions were observed by members of the training team. Post-training audio recordings of consultations from each general practitioner and nurse in the practices were transcribed and read to provide a narrative overview of the incorporation of WISE skills and tools into consultations. Face-to-face semi-structured interviews were conducted with staff post-training.Two practices out of 14 deemed eligible agreed to take part. Each practice attended two sessions, although a third session on consultation skills training was needed for one practice. Fifty-four post-training consultations were recorded from 15 clinicians. Two members of staff were interviewed at each practice. Significant elements of the training form and methods of delivery fitted contemporary practice. There were logistical problems in getting a whole practice to attend both sessions, and administrative staff founds some sections irrelevant. Clinicians reported problems incorporating some of the tools developed for WISE, and this was confirmed in the overview of consultations, with limited overt use of WISE tools and missed opportunities to address patients' self-management needs.The formative evaluation approach and attention to normalisation process theory allowed the training team to make adjustments to content and delivery and ensure appropriate staff attended each session. The content of the course was simplified and focussed more clearly on operationalising the WISE approach. The patient arm of the approach was strengthened by raising expectations of a change in approach to self-care support by their practice.The effective management of long-term conditions is a key focus of health for which policy and support for self-management has been a core com
New insights on the pathogenesis of pyloric stenosis of infancy. A review with emphasis on the hyperacidity theory  [PDF]
Ian M. Rogers
Open Journal of Pediatrics (OJPed) , 2012, DOI: 10.4236/ojped.2012.22017
Abstract: A review is presented on the theories concerning the cause of pyloric stenosis with emphasis on the primary position of inherited hyperacidity in pathogenesis. Existing theories are critically analysed and the hyperacidity theory is precisely defined in the light of recent physiological insights into the gastrointestinal hormone motilin. The progressive fixed fasting hypergastrinaemia within the first few weeks of life will, in the baby who inherits acid secretion at the top of the normal range, produce hyperacidity of sufficient severity to trigger the process of acid-induced work hypertrophy of the pylorus. The potential contribution of motilin is discussed. The baby who inherits a normal gastric acidity will not reach acid levels severe enough to trigger sphincter hypertrophy despite the early gastrin stimulus. The potential threat will cease when gastrin naturally declines with age and the pyloric canal becomes wider. Genetic factors clearly must also be involved and these are separately discussed.
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