524 research outputs found
Effects of ultrasound on Transforming Growth Factor-beta genes in bone cells
Therapeutic ultrasound (US) is a widely used form of biophysical stimulation that is increasingly applied to promote fracture healing. Transforming growth factor-beta (TGF-beta), which is encoded by three related but different genes, is known to play a major part in bone growth and repair. However, the effects of US on the expression of the TGF-beta genes and the physical acoustic mechanisms involved in initiating changes in gene expression in vitro, are not yet known. The present study demonstrates that US had a differential effect on these TGF-beta isoforms in a human osteoblast cell line, with the highest dose eliciting the most pronounced up-regulation of both TGF-beta1 and TGF-beta3 at 1 hour after treatment and thereafter declining. In contrast, US had no effect on TGF-beta2 expression. Fluid streaming rather than thermal effects or cavitation was found to be the most likely explanation for the gene responses observed in vitro
Service level agreement framework for differentiated survivability in GMPLS-based IP-over-optical networks
In the next generation optical internet, GMPLS based IP-over-optical networks, ISPs will be required to support a wide variety of applications each having their own requirements. These requirements are contracted by means of the SLA. This paper describes a recovery framework that may be included in the SLA contract between ISP and customers in order to provide the required level of survivability. A key concern with such a recovery framework is how to present the different survivability alternatives including recovery techniques, failure scenario and layered integration into a transparent manner for customers. In this paper, two issues are investigated. First, the performance of the recovery framework when applying a proposed mapping procedure as an admission control mechanism in the edge router considering a smart-edge simple-core GMPLS-based IP/WDM network is considered. The second issue pertains to the performance of a pre-allocated restoration and its ability to provide protected connections under different failure scenarios
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Investigating the role of collagen in peripheral nerve biomechanics
Abstract not available
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Effects of therapeutic ultrasound on osteoblast gene expression
Ultrasound (US) is commonly used as a physiotherapy aid for a number of types of injury to soft connective tissues and for fracture healing. However, the precise effects of therapeutic US on tissue healing processes are not clearly understood, although they are likely to involve changes in key cellular functions. The present study has therefore examined the effects of several US intensity levels on the activity of two bone-associated proteins, alkaline phosphatase (ALP) and osteopontin (OP) in a human cell line, MG63, using RT-PCR. ALP showed progressively higher expression with increasing US intensities, whereas OP responded differently, showing down-regulation at 120 mW/cm2, the lowest US exposure. OP expression was considerably less affected overall compared with the relative response of ALP to the same US doses. The results show that there is a differential response to therapeutic levels of US, since ALP and OP clearly exhibited gene-specific response profiles. These findings suggest that modifying the parameters of US exposure could be used to improve repair and regeneration processes and enhance the clinical efficacy of implanted biomaterials for tissue engineering
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Gene expression profiling of bone cells on smooth and rough titanium surfaces
Titanium (Ti) and Ti alloys are widely used as dental and orthopaedic implants, but the effects of the surface characteristics of these materials on the response of cells and target tissues is not well understood. The present study has therefore examined the effects of a rough Ti (RT) and a smooth Ti (ST) surface on human bone cells in vitro. Scanning electron microscopy showed attachment and spreading of cells on both surfaces. Expression profiling using ATLAS™ gene arrays showed marked differences in gene responses after 3 h of culture. A number of osteoblast genes were identified as "roughness response" genes on the basis of changes in expression on the RT compared with the ST surfaces. The surface roughness of Ti was thus found to have a profound effect on the profile of genes expressed by the bone cells, and suggests that improvements in the biological activity and possibly the clinical efficacy of these materials could be achieved by selective regulation of gene expression mediated by controlled modification of Ti surface
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Standardized Patient Methodology to Assess Refractive Error Reproducibility
Purpose. Standardized patient (SP) methodology is the gold standard for evaluating clinical practice. This approach was used to investigate the content of typical optometric eyecare in England and the reproducibility of refractive error measurement using prescriptions obtained by three SPs.
Methods. The three SPs were independently examined by three to four expert optometric clinicians to obtain “benchmark” estimates of refractive error. One hundred two community optometrists consented to be visited by three SPs who were trained to provide accurate responses during the examinations. The spectacle prescriptions obtained by the SPs were analyzed for spherical equivalent refraction, spherical power and cylindrical power using astigmatic decomposition.
Results. The spherical equivalent refractions were found to be within ±0.25 D of the benchmark on average 81% of the time and within ±0.50 D 97% of the time. The spherical power was within ±0.25 D 90% of the time and within ±0.50 D 98% of the time. The cylindrical power agreed within ±0.25 D 93% of the time and within ±0.50 D 100% of the time. Based on reproducibility limits data obtained for all six eyes, any two optometrists would differ in their estimation of spherical equivalent refraction by no more than 0.75 D in 95% of repeated measures. The astigmatic data (C0 and C45) show that optometrists will differ in their estimation of the C0 component by between 0.25 and 0.61 D and for the C45 component by between 0.22 and 0.47 D in 95% of repeated measures.
Conclusions. The agreement between our data and the results of other similar studies support the conclusions that subjective refractive findings are reproducible to approximately ±0.75 D when performed by multiple optometrists in patients of different age groups and levels of ametropia. SPs are an effective way of measuring reproducibility of refractive error and should be considered for further comparative analysis in different age groups and different levels of ametropia
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Assessing the impact of multi-channel BLE beacons on fingerprint-based positioning
Bluetooth Low Energy (BLE) beacons are attractive for indoor location due to their ease of deployment, wide support on consumer devices and low cost. Co-ordinate location can be estimated using radio fingerprinting techniques applied to Received Signal Strength (RSS) values from BLE beacons. Earlier work on BLE fingerprinting has noted that the separate BLE advertising channels can exhibit different RSS values, although modern consumer devices do not provide channel information and therefore report a composite RSS with artificially inflated variance that can lead to reduced positioning accuracy. In this work we quantify how often this channel dispersion occurs in typical environments, what the extent of the dispersion is, and what impact it has on positioning. Furthermore we explore how to obtain channel information when using today's consumer devices. We find that the dispersion is both common and significant and leads to significantly reduced positioning accuracy; in our experiments only 10% of composite variances were within 1 dBm of an individual channel's variance, and 40% of composite variances were at least 4 dBm greater. We also show that the behaviour of the channels is sufficiently distinct that a fingerprinting scheme that uses a signal map for each achieves significantly increased positioning accuracy (up to 3 m)
Balancing patient-centered and safe pain care for non-surgical inpatients: clinical and managerial perspectives
Background:
Hospitals and clinicians aim to deliver care that is safe. Simultaneously, they are ensuring that care is patient-centered, meaning that it is respectful of patients’ values, preferences, and experiences. However, little is known about delivering care in cases where these goals may not align. For example, hospitals and clinicians are facing the daunting challenge of balancing safe and patient-centered pain care for nonsurgical patients, due to lack of comprehensive care guidelines and complexity of this patient population.
Methods:
To gather clinical and managerial perspectives on the importance, feasibility, and strategies used to balance patient-centered care (PCC) and safe pain care for nonsurgical inpatients, we conducted in-depth, semi-structured interviews with hospitalists (n=10), registered nurses (n=10), and health care managers (n=10) from one healthcare system in the Midwestern United States. We systematically examined transcribed interviews and identified major themes using a thematic analysis approach.
Results:
Participants acknowledged the importance of balancing PCC and safe pain care. They envisioned this balance as a continuum, with certain patients for whom it is easier (e.g., opioid-naĂŻve patient with a fracture), versus more difficult (e.g., patient with opioid use disorder). Participants also reported several strategies they use to balance PCC and safe pain care, including offering alternatives to opioids, setting realistic pain goals and expectations, and using a team approach.
Conclusions:
Clinicians and health care managers use various strategies to balance PCC and safe pain care for nonsurgical patients. Future studies should examine the effectiveness of these strategies on patient outcomes
Clinical perspectives on hospitals’ role in the opioid epidemic
Policymakers, legislators, and clinicians have raised concerns that hospital-based clinicians may be incentivized to inappropriately prescribe and administer opioids when addressing pain care needs of their patients, thus potentially contributing to the ongoing opioid epidemic in the United States. Given the need to involve all healthcare settings, including hospitals, in joint efforts to curb the opioid epidemic, it is essential to understand if clinicians perceive hospitals as contributors to the problem. Therefore, we examined clinical perspectives on the role of hospitals in the opioid epidemic
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