607 research outputs found
Effective mobilities in pseudomorphic Si/SiGe/Si p-channel metal-oxide-semiconductor field-effect transistors with thin silicon capping layers
The room-temperature effective mobilities of pseudomorphic Si/Si0.64Ge0.36/Si p-metal-oxidesemiconductor field effect transistors are reported. The peak mobility in the buried SiGe channel increases with silicon cap thickness. It is argued that SiO2/Si interface roughness is a major source of scattering in these devices, which is attenuated for thicker silicon caps. It is also suggested that segregated Ge in the silicon cap interferes with the oxidation process, leading to increased SiO2/Si interface roughness in the case of thin silicon caps
Developing and internally validating a prognostic model (P Risk) to improve the prediction of psychosis in a primary care population using electronic health records:the MAPPED study
BACKGROUND: An accurate risk prediction algorithm could improve psychosis outcomes by reducing duration of untreated psychosis.
OBJECTIVE: To develop and validate a risk prediction model for psychosis, for use by family doctors, using linked electronic health records.
METHODS: A prospective prediction study. Records from family practices were used between 1/1/2010 to 31/12/2017 of 300,000 patients who had consulted their family doctor for any nonpsychotic mental health problem. Records were selected from Clinical Practice Research Datalink Gold, a routine database of UK family doctor records linked to Hospital Episode Statistics, a routine database of UK secondary care records. Each patient had 5-8Â years of follow up data. Study predictors were consultations, diagnoses and/or prescribed medications, during the study period or historically, for 13 nonpsychotic mental health problems and behaviours, age, gender, number of mental health consultations, social deprivation, geographical location, and ethnicity. The outcome was time to an ICD10 psychosis diagnosis.
FINDINGS: 830 diagnoses of psychosis were made. Patients were from 216 family practices; mean age was 45.3Â years and 43.5Â % were male. Median follow-up was 6.5Â years (IQR 5.6, 7.8). Overall 8-year psychosis incidence was 45.8 (95Â % CI 42.8, 49.0)/100,000 person years at risk. A risk prediction model including age, sex, ethnicity, social deprivation, consultations for suicidal behaviour, depression/anxiety, substance abuse, history of consultations for suicidal behaviour, smoking history and prescribed medications for depression/anxiety/PTSD/OCD and total number of consultations had good discrimination (Harrell's CÂ =Â 0.774). Identifying patients aged 17-100Â years with predicted risk exceeding 1.0Â % over 6Â years had sensitivity of 71Â % and specificity of 84Â %
The relative responsiveness of test instruments can be estimated using a meta-analytic approach:an illustration with treatments for depression
Objectives: We present a meta-analytic method that combines information on treatment effects from different instruments from a network of randomized trials to estimate instrument relative responsiveness. Study Design and Setting: Five depression-test instruments [Beck Depression Inventory (BDI I/II), Patient Health Questionnaire (PHQ9), Hamilton Rating for Depression 17 and 24 items, Montgomery-Asberg Depression Rating] and three generic quality of life measures [EuroQoL (EQ-5D), SF36 mental component summary (SF36 MCS), and physical component summary (SF36 PCS)] were compared. Randomized trials of treatments for depression reporting outcomes on any two or more of these instruments were identified. Information on the within-trial ratios of standardized treatment effects was pooled across the studies to estimate relative responsiveness. Results: The between-instrument ratios of standardized treatment effects vary across trials, with a coefficient of variation of 13% (95% credible interval: 6%, 25%). There were important differences between the depression measures, with PHQ9 being the most responsive instrument and BDI the least. Responsiveness of the EQ-5D and SF36 PCS was poor. SF36 MCS performed similarly to depression instruments. Conclusion: Information on relative responsiveness of several test instruments can be pooled across networks of trials reporting at least two outcomes, allowing comparison and ranking of test instruments that may never have been compared directly.</p
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Cannabidivarin is anticonvulsant in mouse and rat in vitro and in seizure models
Summary
Background and purpose: Phytocannabinoids in Cannabis sativa have diverse
pharmacological targets extending beyond cannabinoid receptors and several exert notable
anticonvulsant effects. For the first time, we investigated the anticonvulsant profile of the
phytocannabinoid cannabidivarin (CBDV) in vitro and in in vivo seizure models.
Experimental approach: The effect of CBDV (1-100ÎŒM) on epileptiform local field
potentials (LFPs) induced in rat hippocampal brain slices by 4-AP application or Mg2+-free
conditions was assessed by in vitro multi-electrode array recordings. Additionally, the
anticonvulsant profile of CBDV (50-200 mg kg-1) in vivo was investigated in four rodent
seizure models: maximal electroshock (mES) and audiogenic seizures in mice, and
pentylenetetrazole (PTZ) and pilocarpine-induced seizures in rat. CBDV effects in
combination with commonly-used antiepileptic drugs were investigated in rat seizures.
Finally, the motor side effect profile of CBDV was investigated using static beam and gripstrength
assays.
Key results: CDBV significantly attenuated status epilepticus-like epileptiform LFPs
induced by 4-AP and Mg2+-free conditions. CBDV had significant anticonvulsant effects in
mES (â„100 mg kg-1), audiogenic (â„50 mg kg-1) and PTZ-induced seizures (â„100 mg kg-1).
CBDV alone had no effect against pilocarpine-induced seizures, but significantly attenuated
these seizures when administered with valproate or phenobarbital at 200 mg kg-1 CBDV.
CBDV had no effect on motor function.
Conclusions and Implications: These results indicate that CBDV is an effective
anticonvulsant across a broad range of seizure models, does not significantly affect normal
motor function and therefore merits further investigation in chronic epilepsy models to justify
human trials
Sand in the wheels, or oiling the wheels, of international finance? : New Labour's appeal to a 'new Bretton Woods'
Tony Blairâs political instinct typically is to associate himself only with the future. As such, his explicit appeal to âthe pastâ in his references to New Labourâs desire to establish a ânew Bretton Woodsâ is sufficient in itself to arouse some degree of analytical curiosity (see Blair 1998a). The fact that this appeal was made specifically in relation to Bretton Woods is even more interesting. The resonant image of the international economic context established by the original Bretton Woods agreements invokes a style and content of policy-making which Tony Blair typically dismisses as neither economically nor politically consistent with his preferred vision of the future (see Blair 2000c, 2001b)
Measuring organisational readiness for patient engagement (MORE) : an international online Delphi consensus study
Date of Acceptance: 28/01/2015. © 2015 Oostendorp et al.; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise statedWidespread implementation of patient engagement by organisations and clinical teams is not a reality yet. The aim of this study is to develop a measure of organisational readiness for patient engagement designed to monitor and facilitate a healthcare organisationâs willingness and ability to effectively implement patient engagement in healthcarePeer reviewedFinal Published versio
Optimizing the colour and fabric of targets for the control of the tsetse fly Glossina fuscipes fuscipes
Background:
Most cases of human African trypanosomiasis (HAT) start with a bite from one of the subspecies of Glossina fuscipes. Tsetse use a range of olfactory and visual stimuli to locate their hosts and this response can be exploited to lure tsetse to insecticide-treated targets thereby reducing transmission. To provide a rational basis for cost-effective designs of target, we undertook studies to identify the optimal target colour.
Methodology/Principal Findings:
On the Chamaunga islands of Lake Victoria , Kenya, studies were made of the numbers of G. fuscipes fuscipes attracted to targets consisting of a panel (25 cm square) of various coloured fabrics flanked by a panel (also 25 cm square) of fine black netting. Both panels were covered with an electrocuting grid to catch tsetse as they contacted the target. The reflectances of the 37 different-coloured cloth panels utilised in the study were measured spectrophotometrically. Catch was positively correlated with percentage reflectance at the blue (460 nm) wavelength and negatively correlated with reflectance at UV (360 nm) and green (520 nm) wavelengths. The best target was subjectively blue, with percentage reflectances of 3%, 29%, and 20% at 360 nm, 460 nm and 520 nm respectively. The worst target was also, subjectively, blue, but with high reflectances at UV (35% reflectance at 360 nm) wavelengths as well as blue (36% reflectance at 460 nm); the best low UV-reflecting blue caught 3Ă more tsetse than the high UV-reflecting blue.
Conclusions/Significance:
Insecticide-treated targets to control G. f. fuscipes should be blue with low reflectance in both the UV and green bands of the spectrum. Targets that are subjectively blue will perform poorly if they also reflect UV strongly. The selection of fabrics for targets should be guided by spectral analysis of the cloth across both the spectrum visible to humans and the UV region
p38 MAPK stress signalling in replicative senescence in fibroblasts from progeroid and genomic instability syndromes
Werner Syndrome (WS) is a human segmental progeria resulting from mutations in a DNA helicase. WS fibroblasts have a shortened replicative capacity, an aged appearance, and activated p38 MAPK, features that can be modulated by inhibition of the p38 pathway. Loss of the WRNp RecQ helicase has been shown to result in replicative stress, suggesting that a link between faulty DNA repair and stress-induced premature cellular senescence may lead to premature ageing in WS. Other progeroid syndromes that share overlapping pathophysiological features with WS also show defects in DNA processing, raising the possibility that faulty DNA repair, leading to replicative stress and premature cellular senescence, might be a more widespread feature of premature ageing syndromes. We therefore analysed replicative capacity, cellular morphology and p38 activation, and the effects of p38 inhibition, in fibroblasts from a range of progeroid syndromes. In general, populations of young fibroblasts from non-WS progeroid syndromes do not have a high level of cells with an enlarged morphology and F-actin stress fibres, unlike young WS cells, although this varies between strains. p38 activation and phosphorylated HSP27 levels generally correlate well with cellular morphology, and treatment with the p38 inhibitor SB203580 effects cellular morphology only in strains with enlarged cells and phosphorylated HSP27. For some syndromes fibroblast replicative capacity was within the normal range, whereas for others it was significantly shorter (e.g. HGPS and DKC). However, although in most cases SB203580 extended replicative capacity, with the exception of WS and DKC the magnitude of the effect was not significantly different from normal dermal fibroblasts. This suggests that stress-induced premature cellular senescence via p38 activation is restricted to a small subset of progeroid syndromes
In vitro comparison of the effects of rough and polished stem surface finish on pressure generation in cemented hip arthroplasty
Background and purpose High pressures around implants can cause bone lysis and loosening. We investigated how pressures are generated around cemented femoral stems
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