139 research outputs found
Biomechanical analysis of two types of osseointegrated transfemoral prosthesis
In the last two decades, osseointegrated prostheses have been shown to be a good alternative for lower limb amputees experiencing complications in using a traditional socket-type prosthesis; however, restraining biomechanical issues, such as peri-prosthetic bone fractures or loosening, are present. To better understand and overcome these limiting issues, and thus reduce the number of implant failures, many studies have investigated the stress distribution on bone and implant during normal daily activities. The aim of this study was a biomechanical analysis of two different osseointegrated implants, a screw-type (OPRA) and a press fit system (OPL, Osseointegrated Prosthetic Limb), to evaluate the stresses generated in bone and prosthesis during a fall. In particular, four scenarios have been experimentally reproduced to determine the loads on the limb during different kinds of fall. For this purpose, a motion capture system and a force plate have been used. Numerical FEM (Finite Element Method) simulations have been performed to compare the behaviour of the OPRA and OPL systems in different fall scenarios. The obtained results showed that a fall backwards due to balance loss is the most stressful scenario among the ones analysed. As regards the comparison between OPRA and OPL devices, it emerged they have similar behaviours in terms of peak values of the stress, but the OPL implant generates larger high-stress areas in the distal femur as compared with the OPRA system
The Children and Young People's Health Partnership Evelina London Model of Care: process evaluation protocol
Introduction Children and young people (CYP) in the
UK have poor health outcomes, and there is increasing
emergency department and hospital outpatient use. To
address these problems in Lambeth and Southwark (two
boroughs of London, UK), the local Clinical Commissioning
Groups, Local Authorities and Healthcare Providers formed
The Children and Young People’s Health Partnership
(CYPHP), a clinical-academic programme for improving
child health. The Partnership has developed the CYPHP
Evelina London model, an integrated healthcare model that
aims to deliver effective, coordinated care in primary and
community settings and promote better self-management
to over approximately 90 000 CYP in Lambeth and
Southwark. This protocol is for the process evaluation of
this model of care.
Methods and analysis Alongside an impact evaluation,
an in-depth, mixed-methods process evaluation will
be used to understand the barriers and facilitators to
implementing the model of care. The data collected
mapped onto a logic model of how CYPHP is expected
to improve child health outcomes. Data collection and
analysis include qualitative interviews and focus groups
with stakeholders, a policy review and a quantitative
analysis of routine clinical and administrative data and
questionnaire data. Information relating to the context of
the trial that may affect implementation and/or outcomes
of the CYPHP model of care will be documented.
Ethics and dissemination The study has been reviewed
by NHS REC Cornwall & Plymouth (17/SW/0275). The
findings of this process evaluation will guide the scaling up
and implementation of the CYPHP Evelina London Model
of Care across the UK. Findings will be disseminated
through publications and conferences, and implementation
manuals and guidance for others working to improve child
health through strengthening health systems.
Trial registration number NCT03461848
Evaluation of a new community-based curriculum in disaster medicine for undergraduates
BACKGROUND: Nowadays, many medical schools include training in disaster medicine in undergraduate studies. This study evaluated the efficacy of a disaster medicine curriculum recently designed for Saudi Arabian medical students. METHODS: Participants were 15 male and 14 female students in their fourth, fifth or sixth year at Jazan University Medical School, Saudi Arabia. The course was held at the Research Center in Emergency and Disaster Medicine and Computer Sciences Applied to the Medical Practice in Novara, Italy. RESULTS: The overall mean score on a test given before the course was 41.0 % and it increased to 67.7 % on the post-test (Wilcoxon test for paired samples: z = 4.71, p < 0.0001). There were no significant differences between the mean scores of males and females, or between students in their fourth, fifth or sixth year of medical school. CONCLUSIONS: These results show that this curriculum is effective for teaching disaster medicine to undergraduate medical students. Adoption of this course would help to increase the human resources available for dealing with disaster situations
1B/(−)IRE DMT1 Expression during Brain Ischemia Contributes to Cell Death Mediated by NF-κB/RelA Acetylation at Lys310
The molecular mechanisms responsible for increasing iron and neurodegeneration in brain ischemia are an interesting area of research which could open new therapeutic approaches. Previous evidence has shown that activation of nuclear factor kappa B (NF-κB) through RelA acetylation on Lys310 is the prerequisite for p50/RelA-mediated apoptosis in cellular and animal models of brain ischemia. We hypothesized that the increase of iron through a NF-κB-regulated 1B isoform of the divalent metal transporter-1 (1B/DMT1) might contribute to post-ischemic neuronal damage. Both in mice subjected to transient middle cerebral artery occlusion (MCAO) and in neuronally differentiated SK-N-SH cells exposed to oxygen-glucose-deprivation (OGD), 1A/DMT1 was only barely expressed while the 1B/DMT1 without iron-response-element (−IRE) protein and mRNA were early up-regulated. Either OGD or over-expression of 1B/(−)IRE DMT1 isoform significantly increased iron uptake, as detected by total reflection X-ray fluorescence, and iron-dependent cell death. Iron chelation by deferoxamine treatment or (−)IRE DMT1 RNA silencing displayed significant neuroprotection against OGD which concomitantly decreased intracellular iron levels. We found evidence that 1B/(−)IRE DMT1 was a target gene for RelA activation and acetylation on Lys310 residue during ischemia. Chromatin immunoprecipitation analysis of the 1B/DMT1 promoter showed there was increased interaction with RelA and acetylation of H3 histone during OGD exposure of cortical neurons. Over-expression of wild-type RelA increased 1B/DMT1 promoter-luciferase activity, the (−)IRE DMT1 protein, as well as neuronal death. Expression of the acetylation-resistant RelA-K310R construct, which carried a mutation from lysine 310 to arginine, but not the acetyl-mimic mutant RelA-K310Q, down-regulated the 1B/DMT1 promoter, consequently offering neuroprotection. Our data showed that 1B/(−)IRE DMT1 expression and intracellular iron influx are early downstream responses to NF-κB/RelA activation and acetylation during brain ischemia and contribute to the pathogenesis of stroke-induced neuronal damage
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RHIC Performance for FY2011 Au+Au Heavy Ion Run
Following the Fiscal Year (FY) 2010 (Run-10) Relativistic Heavy Ion Collider (RHIC) Au+Au run, RHIC experiment upgrades sought to improve detector capabilities. In turn, accelerator improvements were made to improve the luminosity available to the experiments for this run (Run-11). These improvements included: a redesign of the stochastic cooling systems for improved reliability; a relocation of 'common' RF cavities to alleviate intensity limits due to beam loading; and an improved usage of feedback systems to control orbit, tune and coupling during energy ramps as well as while colliding at top energy. We present an overview of changes to the Collider and review the performance of the collider with respect to instantaneous and integrated luminosity goals. At the conclusion of the FY 2011 polarized proton run, preparations for heavy ion run proceeded on April 18, with Au+Au collisions continuing through June 28. Our standard operations at 100 GeV/nucleon beam energy was bracketed by two shorter periods of collisions at lower energies (9.8 and 13.5 GeV/nucleon), continuing a previously established program of low and medium energy runs. Table 1 summarizes our history of heavy ion operations at RHIC
A survey of clinical features of allergic rhinitis in adults
Background: Allergic rhinitis (AR) has high prevalence and substantial socio-economic burden.
Material/Methods: The study included 35 Italian Centers recruiting an overall number of 3383 adult patients with rhinitis (48% males, 52% females, mean age 29.1, range 18\u201345 years). For each patient, the attending physician had to fill in a standardized questionnaire, covering, in particular, some issues such as the ARIA classification of allergic rhinitis (AR), the results of skin prick test (SPT), the kind of treatment, the response to treatment, and the satisfaction with treatment.
Results: Out of the 3383 patients with rhinitis, 2788 (82.4%) had AR: 311 (11.5%) had a mild intermittent, 229 (8.8%) a mild persistent, 636 (23.5%) a moderate-severe intermittent, and 1518 (56.1%) a moderate-severe persistent form. The most frequently used drugs were oral antihistamines (77.1%) and topical corticosteroids (60.8%). The response to treatment was judged as excellent in 12.2%, good in 41.3%, fair in 31.2%, poor in 14.5%, and very bad in 0.8% of subjects. The rate of treatment dissatisfaction was significantly higher in patients with moderate-to-severe AR than in patients with mild AR (p<0.0001). Indication to allergen immunotherapy (AIT) was significantly more frequent (p<0.01) in patients with severe AR than with mild AR. .
Conclusions: These fndings confirm the appropriateness of ARIA guidelines in classifying the AR patients and the association of severe symptoms with unsuccessful drug treatment. The optimal targeting of patients to be treated with AIT needs to be reassessed
A new design approach for customised medical devices realized by additive manufacturing
The aim of this work is the design of a new customised elbow orthosis completely realized by Additive Manufacturing and the development of generative algorithms for parametric modelling and creation of 3D patterns to be adapted to the CAD model. This work describes a method to perfect the design of a custom elbow orthosis. A reverse engineering approach has been used to digitalize the patient’s arm and the subsequent CAD modelling of the structure of the custom elbow orthosis has been performed. In particular, two algorithms have been implemented for the creation of 3D patterns and Voronoi tessellations. Subsequently, FEM analyses have been carried out to validate the design. Finally, a prototype of the elbow orthosis with Voronoi tessellation has been realized by means of the SLS technology. The results obtained have demonstrated that the implemented algorithm solved the problems found during CAD modelling with conventional software. Furthermore, the results of FEM analyses have validated the design choices. All this allowed realizing the prototype by AM technologies without problems. Moreover, the new proposed modelling approaches allows creating, in an interactive way, patterns on complex surfaces. The results of this research activity present innovative elements of originality in the CAD modelling sector, which can contribute to solving problems related to the modelling for Additive Manufacturing. Furthermore, another innovative characteristic of the device is the use of torsion springs that simulate the action of physiotherapists during exercises for patient rehabilitation
Additively manufactured textiles and parametric modelling by generative algorithms in orthopaedic applications
Purpose: The purpose of this paper is to implement a new process aimed at the design and production of orthopaedic devices fully manufacturable by additive manufacturing (AM). In this context, the use of generative algorithms for parametric modelling of additively manufactured textiles (AMTs) also has been investigated, and new modelling solutions have been proposed. Design/methodology/approach: A new method for the design of customised elbow orthoses has been implemented. In particular, to better customise the elbow orthosis, a generative algorithm for parametric modelling and creation of a flexible structure, typical of an AMT, has been developed. Findings: To test the developed modelling algorithm, a case study based on the design and production of an elbow orthosis made by selective laser sintering was investigated. The obtained results have demonstrated that the implemented algorithm overcomes many drawbacks typical of the traditional CAD modelling approaches. The parametric CAD model of the orthosis obtained through the new approach is characterised by a flexible structure with no deformations or mismatches and has been effectively used to produce the prototype through AM technologies. Originality/value: The obtained results present innovative elements of originality in the CAD modelling sector, which can contribute to solving problems related to modelling for AM in different application fields
New customized elbow orthosis made by additive manufacturing
Orthoses are additional devices that help people with disabilities. The focus of this work is the design and manufacture of a new customized elbow orthosis completely made by Additive Manufacturing (AM). One of the innovative characteristic of the device is the use of torsion springs that simulate the action of physiotherapists during exercises for patient rehabilitation. Parametric modeling approach based on generative algorithms was used to design the device. Finally, FEM analyses have been performed to validate the design
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