bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modular endoprosthetic replacement for tumours of the proximal femur
Authors: Chandrasekar C. R. , Grimer R. J. , Carter S. R. , Tillman R. M. , Abudu A. , Buckley L. 
Published: December 2008

Endoprosthetic replacement of the proximal femur may be required to treat primary bone tumours or destructive metastases either with impending or established pathological fracture. Modular prostheses are available off the shelf and can be adapted to most reconstructive situations for this purpose. We have assessed the clinical and functional outcome of using the METS (Stanmore Implants Worldwide) modular tumour prosthesis to reconstruct the proximal femur in 100 consecutive patients between 2001 and 2006. We compared the results with the published series for patients managed with modular and custom-made endoprosthetic replacements for the same conditions. There were 52 males and 48 females with a mean age of 56.3 years (16 to 84) and a mean follow-up of 24.6 months (0 to 60). In 65 patients the procedure was undertaken for metastases, in 25 for a primary bone tumour, and in ten for other malignant conditions. A total of 46 patients presented with a pathological fracture, and 19 presented with failed fixation of a previous pathological fracture. The overall patient survival was 63.6% at one year and 23.1% at five years, and was significantly better for patients with a primary bone tumour than for those with metastatic tumour (82.3% vs 53.3%, respectively at one year (p = 0.003)). There were six early dislocations of which five could be treated by closed reduction. No patient needed revision surgery for dislocation. Revision surgery was required by six (6%) patients, five for pain caused by acetabular wear and one for tumour progression. Amputation was needed in four patients for local recurrence or infection. The estimated five-year implant survival with revision as the endpoint was 90.7%. The mean Toronto Extremity Salvage score was 61% (51% to 95%). The implant survival and complications resulting from the use of the modular system were comparable to the published series of both custom-made and other modular proximal femoral implants. We conclude that at intermediate follow-up the modular tumour prosthesis for proximal femur replacement provides versatility, a low incidence of implant-related complications and acceptable function for patients with metastatic tumours, pathological fractures and failed fixation of the proximal femur. It also functions as well as a custom-made endoprosthetic replacement.
Alterations in femoral strain following hip resurfacing and total hip replacement
Authors: Deuel C. R. , Jamali A. A. , Stover S. M. , Hazelwood S. J. 
Published: December 2008

Bone surface strains were measured in cadaver femora during loading prior to and after resurfacing of the hip and total hip replacement using an uncemented, tapered femoral component. In vitro loading simulated the single-leg stance phase during walking. Strains were measured on the medial and the lateral sides of the proximal aspect and the mid-diaphysis of the femur. Bone surface strains following femoral resurfacing were similar to those in the native femur, except for proximal shear strains, which were significantly less than those in the native femur. Proximomedial strains following total hip replacement were significantly less than those in the native and the resurfaced femur.These results are consistent with previous clinical evidence of bone loss after total hip replacement, and provide support for claims of bone preservation after resurfacing arthroplasty of the hip.
Unicompartmental or total knee replacement
Authors: Newman J. , Pydisetty R. V. , Ackroyd C. 
Published: December 2008

Between 1989 and 1992 we had 102 knees suitable for unicompartmental knee replacement (UKR). They were randomised to receive either a St Georg Sled UKR or a Kinematic modular total knee replacement (TKR). The early results demonstrated that the UKR group had less complications and more rapid rehabilitation than the TKR group. At five years there were an equal number of failures in the two groups but the UKR group had more excellent results and a greater range of movement. The cases were reviewed by a research nurse at 8, 10 and 12 years after operation. We report the outcome at 15 years follow-up. A total of 43 patients (45 knees) died with their prosthetic knees intact. Throughout the review period the Bristol knee scores of the UKR group have been better and at 15 years 15 (71.4%) of the surviving UKRs and 10 (52.6%) of the surviving TKRs had achieved an excellent score. The 15 years survivorship rate based on revision or failure for any reason was 24 (89.8%) for UKR and 19 (78.7%) for TKR. During the 15 years of the review four UKRs and six TKRs failed. The better early results with UKR are maintained at 15 years with no greater failure rate. The median Bristol knee score of the UKR group was 91.1 at five years and 92 at 15 years, suggesting little functional deterioration in either the prosthesis or the remainder of the joint. These results justify the increased use of UKR.
The Long Oblique Revision component in revision arthroplasty of the hip
Authors: Landor I. , Vavrik P. , Jahoda D. , Pokorny D. , Tawa A. , Sosna A. 
Published: December 2008

Migration of the acetabular component may give rise to oval-shaped bone defects in the acetabulum. The oblong implant is designed to fill these defects and achieve a stable cementless anchorage with no significant bone loss. We prospectively reviewed 133 oblong long oblique revision components at a mean follow-up of 9.74 years (0.6 to 14). All had been used in revisions for defects of type IIB to IIIB according to Paprosky. Aseptic loosening was the reason for revision in 11 cases (8.3%) and deep infection in seven (5.3%). The probability of implant survival over a 12-year follow-up estimated by the Kaplan-Meier method gave a survival rate of 0.85% respectively 0.90% when deep infection was excluded as the endpoint.Our study supports the use of these components in defects from IIB to IIIA. The main precondition for success is direct contact of more than half of the surface of the implant with the host acetabular bone.
A Systematic Review of Upper Limb Rehabilitation for Adults With Traumatic Brain Injury
Authors: Lannin Natasha A. , McCluskey Annie 
Published: December 2008

AbstractObjective:To summarise the effect of upper limb rehabilitation interventions on motor function in adults with traumatic brain injury.Data sources:Databases were last searched on August 2, 2008. Sources included the Cochrane Central Register of Controlled Trials (CENTRAL); Cochrane Database of Systematic Reviews, the Database of Effectiveness Reviews; MEDLINE, EMBASE, CINAHL, Physiotherapy Evidence Database (PEDro), Occupational Therapy Systematic Evaluation of Evidence database (OTseeker); Google Scholar; and reference lists of included studies.Review methods:Two reviewers determined whether retrieved abstracts met the inclusion criteria: systematic reviews and randomised controlled trials (RCTs); English language; adult participants; ≥ 50% of study participants with a brain injury; interventions designed to improve upper limb motor function. Included papers were appraised for: study design, participants, therapy approach, therapy protocol (indications, contra-indications, intensity and duration), safety and adverse events, and outcomes. The methodological quality of RCTs was rated using the PEDro scale (1–10 highest). Methodology of systematic reviews was rated using the QUOROM criteria.Results:Of the 333 references identified, six were appraised: three systematic reviews and three RCTs. Methodological quality was high for two RCTs, and moderate for one, based on the PEDro scale score. Interventions included upper limb casting, electrical stimulation, and coordination training using meal preparation tasks (making a sandwich and hot drink). In the latter trial, practice of functional kitchen tasks improved fine motor coordination speed on one of four Jebsen-Taylor hand function subtests by 9.38 seconds (95% CI, 1.1 to 17.7). Remaining trials reported non-significant effects for hand function. Small sample sizes and limited reporting of results reduce the interpretability of two RCTs.Conclusion:No conclusive evidence was found on which to base upper limb motor rehabilitation after brain injury, however, lack of evidence does not equate to evidence of no effect.
Managing Challenging Behaviour of People With Acquired Brain Injury in Community Settings: The First 7 Years of a Specialist Clinical Service
Authors: Kelly Glenn , Parry Ann 
Published: December 2008

AbstractThis article provides a review of the development and clinical practice of the ABI Behaviour Consultancy (the ‘Consultancy’), a specialist clinical service that provides outreach behaviour management support across the state of Victoria, Australia, to people with acquired brain injury (ABI) and their social network (i.e., family members, friends, support workers, and therapists). The Consultancy is a small, unique service that has developed ways of providing behaviour management strategies in community settings, despite the difficulties presented by changing and uncontrolled environments. The aim of this article is to provide a detailed account of this service. Information from the first 7 years of full operation, 1998 to 2004, is presented, during which a small number of psychologists saw more than 800 clients. A detailed description is given of behaviours referred and associated risks, assessment procedures, intervention approaches, and research activity. A variety of key service aspects are detailed, including the qualifications required of specialised staff, the service funding levels, and funding and service issues. These detailed accounts of service delivery are placed in the context of several major themes: specialist versus generalist services, the deployment of targeted interventions throughout the lifespan of a brain-injured individual, the role of specialist behaviour management services in the continuum of brain-injury support services, and broader equity issues.
Interaction of the porcine reproductive and respiratory syndrome virus nucleocapsid protein with the inhibitor of MyoD family-a domain-containing protein
Authors: Song Cheng , Lu Ray , Bienzle Dorothee , Liu Hsiao-Ching , Yoo Dongwan 
Published: December 2008

Abstract
Porcine reproductive and respiratory syndrome (PRRS) virus is an RNA virus that replicates in the cytoplasm, but the viral nucleocapsid (N) protein localizes specifically in the nucleus and nucleolus of virus-infected cells. Nuclear localization of N is non-essential for PRRSV replication in cultured cells but has been shown to modulate the pathogenesis of virus in pigs, suggesting that N plays an accessory role in the nucleus during infection. We identified by yeast two-hybrid screening the inhibitor of MyoD family-a (I-mfa) domain-containing protein (HIC) as a cellular partner for PRRS virus (PRRSV) N protein. This protein is a homolog of human HIC, a recently identified cellular transcription factor. The specific interaction of PRRSV N with HIC was confirmed in cells by mammalian two-hybrid assay and co-immunoprecipitation and in vitro by GST pull-down assay. HIC is a zinc-binding protein and confocal microscopy demonstrated co-localization of N with the HIC-p40 isomer in the nucleus and nucleolus, and in the cytoplasm with HIC-p32, which is the N-terminal truncation of HIC-p40. The porcine homolog of HIC is universally expressed in pig tissues including alveolar macrophages. The interaction of viral capsid with the cellular transcription factor implicates a possible regulation of host cell gene expression by the N protein during PRRSV infection.
Clinical Development of Ixabepilone and Other Epothilones in Patients with Advanced Solid Tumors
Authors: Rivera Edgardo , Lee Joyce , Davies Angela 
Published: December 2008

Abstract
Chemotherapy efficacy in patients with solid tumors is influenced by primary and acquired multidrug resistance (MDR). Epothilones represent a novel class of microtubule inhibitors with lower susceptibility to drug resistance and efficacy in taxane-resistant tumors. While other epothilones are currently under investigation, ixabepilone is the first epothilone B analogue approved by the U.S. Food and Drug Administration. Ixabepilone has been shown to have preclinical activity in chemotherapy-sensitive and chemotherapy-resistant tumor models, and synergistic antitumor activity with other chemotherapeutic and targeted agents. Single-agent ixabepilone has demonstrated clinical activity in multiple solid tumors including advanced breast, lung, prostate, pancreatic, renal cell, and ovarian cancers. Most notably, efficacy has been demonstrated in patients with metastatic breast cancer (MBC) progressing after treatment with anthracyclines and taxanes. A phase III trial in anthracycline- and taxane-resistant MBC showed superior disease control with ixabepilone plus capecitabine versus capecitabine monotherapy, resulting in its approval. Ixabepilone is also active in chemotherapy-naïve and taxane-resistant hormone-refractory prostate cancer and platinum-resistant non-small cell lung cancer. Neutropenia and peripheral sensory neuropathy are the most common adverse events associated with treatment. This review discusses the challenges of MDR and the data that support the use of epothilones in this setting, focusing on ixabepilone.
Consistent Downscaling of Seismic Inversion Thicknesses to Cornerpoint Flow Models
Authors: Kalla Subhash , White Christopher D. , Gunning James , Glinsky Michael E. 
Published: December 2008

SummaryAccurate reservoir simulation requires data-rich geomodels. In this paper, geomodels integrate stochastic seismic inversion results (for means and variances of packages of meter-scale beds), geologic modeling (for a framework and priors), rock physics (to relate seismic to flow properties), and geostatistics (for spatially correlated variability). These elements are combined in a Bayesian framework. The proposed workflow produces models with plausible bedding geometries, where each geomodel agrees with seismic data to the level consistent with the signal-to-noise ratio of the inversion. An ensemble of subseismic models estimates the means and variances of properties throughout the flow simulation grid.Grid geometries with possible pinchouts can be simulated using auxiliary variables in a Markov chain Monte Carlo (MCMC) method. Efficient implementations of this method require a posterior covariance matrix for layer thicknesses. Under assumptions that are not too restrictive, the inverse of the posterior covariance matrix can be approximated as a Toeplitz matrix, which makes the MCMC calculations efficient. The proposed method is examined using two-layer examples. Then, convergence is demonstrated for a synthetic 3D, 10,000 trace, 10 layer cornerpoint model. Performance is acceptable.The Bayesian framework introduces plausible subseismic features into flow models, whilst avoiding overconstraining to seismic data, well data, or the conceptual geologic model. The methods outlined in this paper for honoring probabilistic constraints on total thickness are general, and need not be confined to thickness data obtained from seismic inversion: Any spatially dense estimates of total thickness and its variance can be used, or the truncated geostatistical model could be used without any dense constraints.
Mobilization of Entrapped Organic Fluids by Elastic Waves and Vibrations
Authors: Iassonov Pavel P. , Beresnev Igor A. 
Published: December 2008

Summary
The organic fluids entrapped in pore constrictions by capillary forces can be mobilized by the application of elastic-wave vibrations because of the nudging effect, which allows quantitative description. The model used for such calculations is a single-pore channel with converging/diverging geometry, in which the organic phase is entrapped as a continuous blob occupying several adjacent pores. The ganglion is released from the constriction when the wave-acceleration amplitude exceeds a threshold value that scales with the frequency as A/f = a constant. This means that the wave intensity is the only required criterion for the release. In an ensemble of ganglia, the percentage of them mobilized and, therefore, the flow rate increases with the amplitude and decreases with frequency. The vibrations are inefficient for mobilization if the frequency is sufficiently high. The typical vibratory amplitudes required to produce noticeable increases in the average flow rates are on the order of 10 m/s2 and much higher at the frequencies in excess of approximately 10 Hz. These estimates provide guidelines for the possible applications of elastic-wave stimulation of organic-fluid flow in porous environments.
Adjoint-Based Well-Placement Optimization Under Production Constraints
Authors: Zandvliet M. J. , Handels M. , Essen G. M. van , Brouwer D. R. , Jansen J. D. 
Published: December 2008

Summary
Determining the optimal location of wells with the aid of an automated search method can significantly increase a project's net present value (NPV) as modeled in a reservoir simulator. This paper has two main contributions: first, to determine the effect of production constraints on optimal well locations and, second, to determine optimal well locations using a gradient-based optimization method. Our approach is based on the concept of surrounding the wells whose locations have to be optimized by so-called pseudowells. These pseudowells produce or inject at a very low rate and, thus, have a negligible influence on the overall flow throughout the reservoir. The gradients of NPV over the lifespan of the reservoir with respect to flow rates in the pseudowells are computed using an adjoint method. These gradients are used subsequently to approximate improving directions (i.e., directions to move the wells to achieve an increase in NPV), on the basis of which improving well locations can be determined. The main advantage over previous approaches such as finite-difference or stochastic-perturbation methods is that the method computes improving directions for all wells in only one forward (reservoir) and one backward (adjoint) simulation. The process is repeated until no further improvements are obtained. The method is applied to three waterflooding examples.
Ensemble-Level Upscaling for Efficient Estimation of Fine-Scale Production Statistics
Authors: Chen Yuguang , Durlofsky Louis J. 
Published: December 2008

SummaryUpscaling is often needed in reservoir simulation to coarsen highly detailed geological descriptions. Most existing upscaling procedures aim to reproduce fine-scale results for a particular geological model (realization). In this work, we develop and test a new approach, ensemble-level upscaling, for efficiently generating up-scaled two-phase flow parameters (e.g., upscaled relative permeabilities) for multiple geological realizations. The ensemble-level upscaling approach aims to achieve agreement between the fine-and coarse-scale flow models at the ensemble level, rather than realization-by-realization agreement, as is the intent of existing upscaling techniques. For this purpose, flow-based upscaling calculations are combined with a statistical procedure based on a cluster analysis. This approach allows us to compute numerically the upscaled two-phase flow functions for only a small fraction of the coarse blocks. For the majority of blocks, these functions are estimated statistically on the basis of single-phase velocity information (attributes), determined when the upscaled single-phase parameters are calculated. The procedure is designed to maintain close correspondence between the cumulative distribution functions (CDFs) for the numerically computed and statistically estimated two-phase flow functions. We apply the method to 2D synthetic models of multiple realizations for uncertainty quantification. Models with different geological heterogeneity and fluid-mobility ratios are considered. It is shown that the method consistently corrects the biases evident in primitive coarse-scale predictions and can capture the ensemble statistics (e.g., P50, P10, P90) of the fine-scale results almost as accurately as the full flow-based upscaling procedures but with much less computational effort. The overall approach is flexible and can be used with any combination of upscaling procedures.
Parallel Unstructured-Solver Methods for Simulation of Complex Giant Reservoirs
Authors: Fung Larry S. K. , Dogru Ali H. 
Published: December 2008

Summary
The major issues for parallel solvers in a modern reservoir simulator are robustness, scalability, efficiency, and flexibility. There is significant interest in running fast field-scale simulations for complex giant Middle Eastern reservoirs, which will require tens of millions to hundreds of millions of grid cells to give reasonable resolution. At the same time, significant geologic complexity will require the treatment of dual-permeability regions, faulting and fractures, and high variations of reservoir and fluid properties. Of course, the methods should also work well for extracted-sector simulation with local grid refinements in both the structured and unstructured discretization. The preconditioning methods considered in this work include both the single-stage and multistage frameworks. In the single-stage framework, a novel method is considered in addition to the well-known variants of incomplete lower-upper (ILU) factorizations [ILU0, ILU(k), and ILUT]. The new method is a highly parallel method, which, in this paper, will be referred to as the unstructured line-solve power-series (LSPS) method. The method will be discussed and contrasted in light of key issues for parallel linear solvers. The unstructured LSPS has certain interesting properties in the parallel construct, which make it a highly effective component.
The multistage method researched in this work is of the constraint pressure residual (CPR) framework. The method uses approximate pressure solve as the first-stage preconditioning to the full-system preconditioning. A number of original adaptations based on this concept were researched. Here, the use of the parallel algebraic multigrid (PAMG) method and other single-level methods mentioned previously in combinations within the multistage CPR framework were explored. Certain methods constructed in this way are found to be highly efficient, scalable, and robust. The methods developed are discussed, and several test problems are included, in this paper. The largest simulation model tested to date using these solver methods is a 172-million-cell full-field model of a supergiant carbonate complex with more than 3,000 wells and 60 years of history simulation.