Rapid prototyping of bone tissue engineering constructs often utilizes elevated temperatures, organic solvents and or UV light for materials processing. These harsh conditions may prevent the ...incorporation of cells and therapeutic proteins in the fabrication processes. Here we developed a method for using bioprinting to produce constructs from a thermoresponsive microparticulate material based on poly(lactic-co-glycolic acid) at ambient conditions. These constructs could be engineered with yield stresses of up to 1.22 MPa and Young's moduli of up to 57.3 MPa which are within the range of properties of human cancellous bone. Further study showed that protein-releasing microspheres could be incorporated into the bioprinted constructs. The release of the model protein lysozyme from bioprinted constructs was sustainted for a period of 15 days and a high degree of protein activity could be measured up to day 9. This work suggests that bioprinting is a viable route to the production of mechanically strong constructs for bone repair under mild conditions which allow the inclusion of viable cells and active proteins.
Objective To compare 10 year revision rates for frequently used types of primary total hip replacement to inform setting of a new benchmark rate in England and Wales that will be of international ...relevance.Design Retrospective cohort study.Setting National Joint Registry.Participants 239 000 patient records.Main outcome measures Revision rates for five frequently used types of total hip replacement that differed according to bearing surface and fixation mode, encompassing 62% of all primary total hip replacements in the National Joint Registry for England and Wales. Revision rates were compared using Kaplan-Meier and competing risks analyses, and five and 10 year rates were estimated using well fitting parametric models.Results Estimated revision rates at 10 years were 4% or below for four of the five types of total hip replacement investigated. Rates differed little according to Kaplan-Meier or competing risks analysis, but differences between prosthesis types were more substantial. Cemented prostheses with ceramic-on-polyethylene bearing surfaces had the lowest revision rates (1.88-2.11% at 10 years depending on the method used), and cementless prostheses with ceramic-on-ceramic bearing surfaces had the highest revision rates (3.93-4.33%). Men were more likely to receive revision of total hip replacement than were women, and this difference was statistically significant for four of the five prosthesis types.Conclusions Ten year revision rate estimates were all less than 5%, and in some instances considerably less. The results suggest that the current revision rate benchmark should be at least halved from 10% to less than 5% at 10 years. This has implications for benchmarks internationally.
Many different designs of total hip arthroplasty (THA) with varying performance and cost are available. The identification of those which are the most cost-effective could allow significant ...cost-savings. We used an established Markov model to examine the cost effectiveness of five frequently used categories of THA which differed according to bearing surface and mode of fixation, using data from the National Joint Registry for England and Wales. Kaplan-Meier analyses of rates of revision for men and women were modelled with parametric distributions. Costs of devices were provided by the NHS Supply Chain and associated costs were taken from existing studies. Lifetime costs, lifetime quality-adjusted-life-years (QALYs) and the probability of a device being cost effective at a willingness to pay £20 000/QALY were included in the models. The differences in QALYs between different categories of implant were extremely small (< 0.0039 QALYs for men or women over the patient's lifetime) and differences in cost were also marginal (£2500 to £3000 in the same time period). As a result, the probability of any particular device being the most cost effective was very sensitive to small, plausible changes in quality of life estimates and cost. Our results suggest that available evidence does not support recommending a particular device on cost effectiveness grounds alone. We would recommend that the choice of prosthesis should be determined by the rate of revision, local costs and the preferences of the surgeon and patient.
Background: Allergic fungal rhinosinusitis (AFS) is considered to part of the disease spectrum of chronic rhinosinusitis, which affects between five to fifteen per cent of the population. Currently, ...there is uncertainty relating to the pathological process and therefore optimal management of AFS. Studies assessing antifungal use have shown mixed results. The aim of this review is to assess the effect of antifungals on patients with AFS. Methods: A systematic review of the literature to include all published trials searching Pubmed, Medline (Ovid), CINAHL (EBSCO) and the Cochrane central register of controlled trials (CENTRAL) databases. Results: Sixteen studies (two systematic reviews, two meta-analysis, four randomised controlled trials, five prospective cohort studies and three retrospective studies) were included in this review. There was found to be no overall benefit of topical or oral antifungals upon endoscopic findings or patient reported outcome measures in AFS. There were no statistically significant differences in adverse effect profiles between treatment and control groups. Conclusion: There is limited evidence to support the use of topical or oral antifungal agents in patients with AFS. Future research recommendations include large multicentre randomised trials with better matched patient groups and appropriate dosage and timing of antifungals.
Allergic fungal rhinosinusitis (AFS) is considered to part of the disease spectrum of chronic rhinosinusitis, which affects between five to fifteen per cent of the population. Currently, there is ...uncertainty relating to the pathological process and therefore optimal management of AFS. Studies assessing antifungal use have shown mixed results. The aim of this review is to assess the effect of antifungals on patients with AFS.
A systematic review of the literature to include all published trials searching Pubmed, Medline (Ovid), CINAHL (EBSCO) and the Cochrane central register of controlled trials (CENTRAL) databases.
Sixteen studies (two systematic reviews, two meta-analysis, four randomised controlled trials, five prospective cohort studies and three retrospective studies) were included in this review. There was found to be no overall benefit of topical or oral antifungals upon endoscopic findings or patient reported outcome measures in AFS. There were no statistically significant differences in adverse effect profiles between treatment and control groups.
There is limited evidence to support the use of topical or oral antifungal agents in patients with AFS. Future research recommendations include large multicentre randomised trials with better matched patient groups and appropriate dosage and timing of antifungals.
A fifty-four year old woman underwent colonoscopy due to symptoms of altered bowel habit and weight loss. There was a malignant looking lesion at her rectosigmoid junction Fig. 1a which was confirmed ...histologically to be a moderately differentiated adenocarcinoma. Although the blood results were normal, her CT scan and MRI Fig 2a showed an apple core lesion at rectosigmoid junction which was deemed to be Stage IIIC (T4aN2aM0).
Traditional management of mucoceles involve drainage using Functional Endoscopic Sinus Surgery (FESS) and if required an external approach. These techniques may dramatically alter the normal anatomy ...and function of the sinuses and are associated with significant complications. Balloon dilatation of the sinus ostia is a minimally invasive technique that has been licensed for use in chronic sinusitis. We report the use of this novel technique in the management of a frontal sinus mucocele in a 47-year old female. The frontal sinus was successfully cannulated, dilated and drained. The patient made a good post-operative recovery and remained asymptomatic at 6 months. We believe this to be a safe and effective technique for the management of mucoceles in the acute phase.
Abstract
Soft-elasticity in monodomain liquid crystal elastomers (LCEs) is promising for impact-absorbing applications where strain energy is ideally absorbed at constant stress. Conventionally, ...compressive and impact studies on LCEs have not been performed given the notorious difficulty synthesizing sufficiently large monodomain devices. Here, we use direct-ink writing 3D printing to fabricate bulk (>cm
3
) monodomain LCE devices and study their compressive soft-elasticity over 8 decades of strain rate. At quasi-static rates, the monodomain soft-elastic LCE dissipated 45% of strain energy while comparator materials dissipated less than 20%. At strain rates up to 3000 s
−1
, our soft-elastic monodomain LCE consistently performed closest to an ideal-impact absorber. Drop testing reveals soft-elasticity as a likely mechanism for effectively reducing the severity of impacts – with soft elastic LCEs offering a Gadd Severity Index 40% lower than a comparable isotropic elastomer. Lastly, we demonstrate tailoring deformation and buckling behavior in monodomain LCEs via the printed director orientation.
Yield responses of some economically important crop plants due to
foliar applications of low
concentrations of 28-homobrassinolide (HBR) were studied in experiments
conducted at research
stations and ...in farmers' fields in India during 1989–95. Foliar
sprays of different concentrations of
HBR were applied at tillering and spike/panicle initiation in wheat
(0·5 and 1·0 mg/l) and rice (0·25,
0·50 and 1·00 mg/l); at flowering and pegging in groundnut
(0·25 and 0·50 mg/l); 30 and 45 days after
sowing (DAS) in mustard (0·25 and 0·50 mg/l); 25 and 35 days
after emergence in potato (0·25 and
0·50 mg/l); and 30, 50, 70 DAS in cotton (0·1 and 1·0
mg/l). The HBR treatments significantly (P<0·05 and
P<0·01) increased grain yields in wheat, rice and mustard,
pod yields in groundnut, tuber
yields in potato and seed cotton yields, over control. The extent of yield
improvement due to HBR
was influenced by crop species, concentration of HBR, plant growth stage at
application and frequency of application.
One of the most important atomic properties governing an element's chemical behavior is the energy required to remove its least-bound electron, referred to as the first ionization potential. For the ...heaviest elements, this fundamental quantity is strongly influenced by relativistic effects which lead to unique chemical properties. Laser spectroscopy on an atom-at-a-time scale was developed and applied to probe the optical spectrum of neutral nobelium near the ionization threshold. The first ionization potential of nobelium is determined here with a very high precision from the convergence of measured Rydberg series to be 6.626 21±0.000 05 eV. This work provides a stringent benchmark for state-of-the-art many-body atomic modeling that considers relativistic and quantum electrodynamic effects and paves the way for high-precision measurements of atomic properties of elements only available from heavy-ion accelerator facilities.
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