bluuebunny/crossref_metadata_2025 huggingface dataset:
Family Medicine and Internal Medicine Physicians’ Attitudes and Beliefs About Depression
Authors: Hooper Lisa M. , Epstein Steven A. , Qu Lixin , Hannah Natalie J.
Published: December 2010

Studies have long shown that some patients receive less than optimal care for depression in primary care settings. However, few studies have uncovered factors that predict and explain this deficiency. The authors administered a survey to 408 primary care physicians. They examined how physicians’ attitudes (eg, feeling positively or negatively about treating depression in their patients), physicians’ beliefs (eg, beliefs about what their patients think and prefer in terms of depression care), and demographic characteristics (independent variables) predicted optimal depression care (dependent variable). Using logistical regression analyses, they identified differences in treatment decisions between family and internal medicine physicians. Physicians’ specialty and race (family physicians and white physicians were more likely to prescribe a medication) were unique determinants of whether the physician treated depression by prescribing medication; physicians’ specialty and race (family physicians and nonwhite physicians were more likely to provide office-based counseling) were unique determinants of whether the physician treated depression by providing office-based counseling; physicians’ beliefs about depression care and physician age were unique statistically significant determinants of whether the physician treated depression by providing a referral to a mental health specialist. These findings help clarify how physicians’ specialty and beliefs about depression care influence treatment. In addition, the results in this study suggest that there are differences between family and internal medicine physicians in terms of their practice patterns and beliefs in types of treatment that patients would be willing to receive. Implications for future research on primary care depression treatment are discussed.
Increased Anxiety and Length of Treatment Associated With Depressed Patients Who are Readmitted to Collaborative Care
Authors: Angstman Kurt B. , MacLaughlin Kathy L. , Williams Mark D. , Rasmussen Norman H. , DeJesus Ramona S.
Published: December 2010

In 2008, the Institute for Clinical Systems Improvement (ICSI) in Minnesota implemented a model of collaborative care management (CCM) for treatment of depression in primary care. This resulted in significant improvements on both clinical response and remission over usual care, although an increase in utilization metrics has been observed. Mental health comorbidities have previously been significantly associated with an increased likelihood of not responding to initial treatment. This retrospective study hypothesized that patients with mental health comorbidities are more likely to be associated with patients who were readmitted into CCM with recurrent depression. A total of 145 patients who had completed CCM were studied; of these, 32 were diagnosed with recurrent depression and were readmitted to CCM, and 113 were in remission for at least 4 months. There were no statistically significant demographic differences between the 2 groups. The initial screening GAD-7 score for anxiety was significantly increased in the readmission group (12.81 vs 9.20, P = .001) as was the average length of treatment from initial diagnosis to remission (168.09 vs 120.99 days, P = .002). All other initial screening tests were not different between the groups. When controlling for the independent variables by multiple logistic regression, the odds ratio for GAD-7 was 1.1156 (CI = 1.0.192 to 1.2212, P = .0177) and for days of treatment in CCM was 1.0123 (CI = 1.0041 to 1.0206, P = .0033). Patients who are readmitted to CCM for recurrent depression have a statistically increased risk of associated anxiety and a longer treatment course than those who have remained in remission for at least 4 months.
Immune reconstitution is preserved in hematopoietic stem cell transplantation coadministered with regulatory T cells for GVHD prevention
Authors: Gaidot Aline , Landau Dan Avi , Martin Gaëlle Hélène , Bonduelle Olivia , Grinberg-Bleyer Yenkel , Matheoud Diana , Grégoire Sylvie , Baillou Claude , Combadière Béhazine , Piaggio Eliane , Cohen José Laurent
Published: December 2010

Recipient-specific regulatory T cells (rsTreg) can prevent graft-versus-host disease (GVHD) by inhibiting donor T-cell expansion after hematopoietic stem cell transplantation (HSCT) in mice. Importantly, in adult humans, because of thymus involution, immune reconstitution during the first months after HSCT relies on the peripheral expansion of donor T cells initially present in the graft. Therefore, we developed a mouse model of HSCT that excludes thymic output to study the effect of rsTreg on immune reconstitution derived from postthymic mature T cells present within the graft. We showed that GVHD prevention with rsTreg was associated with improvement of the limited immune reconstitution compared with GVHD mice in terms of cell numbers, activation phenotype, and cytokine production. We further demonstrated a preserved in vivo immune function using vaccinia infection and third-party skin-graft rejection models, suggesting that rsTreg immunosuppression was relatively specific of GVHD. Finally, we showed that rsTreg extensively proliferated during the first 2 weeks and then declined. In turn, donor Treg proliferated from day 15 on. Taken together, these results suggest that rsTreg GVHD prevention is associated with improved early immune reconstitution in a model that more closely approximates the biology of allogeneic HSCT in human adults.
How I treat late effects in adults after allogeneic stem cell transplantation
Authors: Savani Bipin N. , Griffith Michelle L. , Jagasia Shubhada , Lee Stephanie J.
Published: December 2010

More than 25 000 allogeneic hematopoietic stem cell transplantations (allo-HCTs) are expected to be performed worldwide in 2010, a number that has been increasing yearly. With broadening indications, more options for allo-HCT, and improvement in survival, by 2020 there may be up to half a million long-term survivors after allo-HCT worldwide. These patients have increased risks for various late complications, which can cause morbidity and mortality. Most long-term survivors return to the care of their local hematologists/oncologists or primary care physicians, who may not be familiar with specialized monitoring recommendations for this patient population. The purpose of this article is to describe practical approaches to screening for and managing these late effects, with the goal of reducing preventable morbidity and mortality associated with allo-HCT.
Endocrine Disruptors and Polycystic Ovary Syndrome (PCOS): Elevated Serum Levels of Bisphenol A in Women with PCOS
Authors: Kandaraki Eleni , Chatzigeorgiou Antonis , Livadas Sarantis , Palioura Eleni , Economou Frangiscos , Koutsilieris Michael , Palimeri Sotiria , Panidis Dimitrios , Diamanti-Kandarakis Evanthia
Published: December 2010

Context:

Bisphenol A (BPA) is a widespread industrial compound used in the synthesis of polycarbonate plastics. In experimental animals, neonatal exposure to BPA results in a polycystic ovary-like syndrome (PCOS) in adulthood. A bidirectional interaction between androgens and BPA levels has been disclosed.

Objective:

To determine BPA levels in PCOS women as well as the association between BPA and hormonal/metabolic parameters compared to a control group.

Design, Setting, and Participants:

Cross-sectional study of 71 PCOS (National Institutes of Health criteria) and 100 normal women, age- and body mass index–matched, in a University hospital setting.

Main Outcome Measures:

Anthropometric, hormonal, metabolic parameters and BPA blood levels were determined. Patients (PCOS) and controls (C) were further subdivided according to body mass index into lean and overweight subgroups, respectively.

Results:

BPA levels were significantly higher in the total PCOS group compared with the controls (1.05±0.56 vs. 0.72±0.37ng/ml, P < 0.001). PCOS women, lean (PCOS-L) and overweight (PCOS-OW), had higher BPA levels compared to the corresponding control group lean (C-L) and overweight (C-OW): (PCOS-L = 1.13±0.63 vs. C-L = 0.70±0.36, P < 0.001) (PCOS-OW = 0.96 ± 0.46 vs. C-OW = 0.72 ± 0.39, P < 0.05). A significant association of testosterone (r = 0.192, P < 0.05) and androstenedione (r = 0.257, P < 0.05) with BPA was observed. Multiple regression analysis for BPA showed significant correlation with the existence of PCOS (r = 0.497, P < 0.05). BPA was also positively correlated with insulin resistance (Matsuda index) in the PCOS group (r = 0.273, P < 0.05).

Conclusions:

Higher BPA levels in PCOS women compared to controls and a statistically significant positive association between androgens and BPA point to a potential role of this endocrine disruptor in PCOS pathophysiology.
Mortality and Morbidity in Cushing's Disease over 50 Years in Stoke-on-Trent, UK: Audit and Meta-Analysis of Literature
Authors: Clayton R. N. , Raskauskiene D. , Reulen R. C. , Jones P. W.
Published: December 2010

Context:

Pituitary ACTH-dependent Cushing's disease (CD) is uncommon, and there are very limited data on long-term mortality.

Objective:

The aim was to summarize what is known about mortality in ACTH-dependent CD, to report on our own data, and to provide a meta-analysis of six other reports that addressed mortality of CD.

Design and Methods:

Vital status of 60 CD patients was recorded as of December 31, 2009, and the standardized mortality ratio (SMR) was calculated and compared with the general population of England and Wales, United Kingdom. A meta-analysis of SMRs from seven studies (including ours) was performed for overall mortality in CD. Where reported (four studies), a similar meta-analysis was performed for those patients whose hypercortisolism was in remission after treatment compared to those patients from the same center with persistent disease.

Results:

1. From Stoke-on-Trent, 51 of 60 patients were female, median age at diagnosis was in the range of 36–46 yr, and median follow-up was 15 yr. There were 13 deaths, nine due to cardiovascular disease. Overall SMR for the whole cohort was 4.8 (95% confidence interval, 2.8–8.3) (P < 0001). SMR for vascular disease was 13.8 (7.2–36.5) (P < 0001). For persistent disease (n = 6), SMR was 16 (6.7–38.4) vs. remission (n = 54) SMR of 3.3 (1.7–6.7); after adjustment for age and sex, relative risk of death for persistent disease was 10.7 (2.3–48.6) (P = 0.002). Hypertension and diabetes mellitus were associated with significantly worse survival. 2. Using a random effects model meta-analysis revealed an overall (remission plus persistent disease) SMR of 2.2 (1.45–3.41) (P < 0.001). Pooled SMR was 1.2 (0.45–3.2) (P = not significant) for patients in remission and 5.5 (2.7–11.3) (P = 0.001) for patients with persistent disease. Persistence of disease, older age at diagnosis, and presence of hypertension and diabetes are the main determinants of mortality.

Conclusions:

Overall mortality in CD is double that of the general population. However, patients with CD in remission fare much better than those with persistence of hypercortisolism, and they appear not to have an increased mortality rate. Hypertension and diabetes mellitus are risk factors for worse outcome. Because diagnosis and treatment of patients are at a young age, much longer follow-up of patients in remission is required before one can be confident that their mortality outcome is no different from that of the general population, especially because cardiovascular risk factors may persist after successful biochemical control of the disease.
Demystifying Disruption: A New Model for Understanding and Predicting Disruptive Technologies
Authors: Sood Ashish , Tellis Gerard J.
Published: December 2010

The failure of firms in the face of technological change has been a topic of intense research and debate, spawning the theory (among others) of disruptive technologies. However, the theory suffers from circular definitions, inadequate empirical evidence, and lack of a predictive model. We develop a new schema to address these limitations. The schema generates seven hypotheses and a testable model relating to platform technologies. We test this model and hypotheses with data on 36 technologies from seven markets. Contrary to extant theory, technologies that adopt a lower attack (“potentially disruptive technologies”) (1) are introduced as frequently by incumbents as by entrants, (2) are not cheaper than older technologies, and (3) rarely disrupt firms; and (4) both entrants and lower attacks significantly reduce the hazard of disruption. Moreover, technology disruption is not permanent because of multiple crossings in technology performance and numerous rival technologies coexisting without one disrupting the other. The proposed predictive model of disruption shows good out-of-sample predictive accuracy. We discuss the implications of these findings.
Tax-Effective Supply Chain Decisions Under China's Export-Oriented Tax Policies
Authors: Hsu Vernon N. , Zhu Kaijie
Published: December 2010

In this paper, we study the impacts of a set of China's export-oriented tax and tariff rules on the optimal supply chain design and operations for a firm that produces its product in China and sells it in markets both inside and outside China. We develop an analytical framework to evaluate four major supply chain structures that we observed in practice. We derive the optimal supply chain decisions for each structure and investigate various business environments under which one of the structures is preferred over the others. Our analysis indicates that the ultimate purpose of a product sold in the China market (i.e., whether it will be consumed domestically or be assembled in another exported product) may have a significant impact on the structure preference. In addition, threshold values exist for several key business parameters over (or under) which certain supply chain structures are favored over others. Managerial insights based on such results are useful for multinational firms who are challenged to develop effective supply chain strategies in the region's increasingly volatile business environment.
Now Playing: DVD Purchasing for a Multilocation Rental Firm
Authors: Baron Opher , Hajizadeh Iman , Milner Joseph
Published: December 2010

This paper studies the problem of purchasing and allocating copies of movies to multiple stores of a movie rental chain. A unique characteristic of this problem is the return process of rented movies. We formulate this problem for new movies as a newsvendor-like problem with multiple rental opportunities for each copy. We provide demand and return forecasts at the store-day level based on comparable movies. We estimate the parameters of various demand and return models using an iterative maximum-likelihood estimation and Bayesian estimation via Markov chain Monte Carlo simulation. Test results on data from a large movie rental firm reveal systematic underbuying of movies purchased through revenue-sharing contracts and overbuying of movies purchased through standard (nonrevenue-sharing) ones. For the movies considered, our model estimates an increase in the average profit per title for new movies by 15.5% and 2.5% for revenue sharing and standard titles, respectively. We discuss the implications of revenue sharing on the profitability of the rental firm.
A Top-Down Approach to Multiname Credit
Authors: Giesecke Kay , Goldberg Lisa R. , Ding Xiaowei
Published: December 2010

A multiname credit derivative is a security that is tied to an underlying portfolio of corporate bonds and has payoffs that depend on the loss due to default in the portfolio. The value of a multiname derivative depends on the distribution of portfolio loss at multiple horizons. Intensity-based models of the loss point process that are specified without reference to the portfolio constituents determine this distribution in terms of few economically meaningful parameters and lead to computationally tractable derivatives valuation problems. However, these models are silent about the portfolio constituent risks. They cannot be used to address applications that are based on the relationship between portfolio and component risks, for example, constituent risk hedging. This paper develops a method that extends these models to the constituents. We use random thinning to decompose the portfolio intensity into a sum of constituent intensities. We show that a thinning process, which allocates the portfolio intensity to constituents, uniquely exists, and is a probabilistic model for the next-to-default. We derive a formula for the constituent default probability in terms of the thinning process and the portfolio intensity, and develop a semi-analytical transform approach to evaluate it. The formula leads to a calibration scheme for the thinning processes and an estimation scheme for constituent hedge sensitivities. An empirical analysis for September 2008 shows that the constituent hedges generated by our method outperform the hedges prescribed by the Gaussian copula model, which is widely used in practice.
Risk Analysis of Collateralized Debt Obligations
Authors: Giesecke Kay , Kim Baeho
Published: December 2010

Collateralized debt obligations, which are securities with payoffs that are tied to the cash flows in a portfolio of defaultable assets such as corporate bonds, play a significant role in the financial crisis that has spread throughout the world. Insufficient capital provisioning due to flawed and overly optimistic risk assessments is at the center of the problem. This paper develops stochastic methods to measure the risk of positions in collateralized debt obligations and related instruments tied to an underlying portfolio of defaultable assets. It proposes an adaptive point process model of portfolio default timing, a maximum likelihood method for estimating point process models that is based on an acceptance/rejection resampling scheme, and statistical tests for model validation. To illustrate these tools, they are used to estimate the distribution of the profit or loss generated by positions in multiple tranches of a collateralized debt obligation that references the CDX High Yield portfolio and the risk capital required to support these positions.
Open reduction and internal fixation of a traumatic diastasis of the pubic symphysis
Authors: Putnis S. E. , Pearce R. , Wali U. J. , Bircher M. D. , Rickman M. S.
Published: January 2011

The aim of this study was to review the number of patients operated on for traumatic disruption of the pubic symphysis who developed radiological signs of movement of the anterior pelvic metalwork during the first post-operative year, and to determine whether this had clinical implications. A consecutive series of 49 patients undergoing internal fixation of a traumatic diastasis of the pubic symphysis were studied. All underwent anterior fixation of the diastasis, which was frequently combined with posterior pelvic fixation. The fractures were divided into groups using the Young and Burgess classification for pelvic ring fractures. The different combinations of anterior and posterior fixation adopted to stabilise the fractures and the type of movement of the metalwork which was observed were analysed and related to functional outcome during the first post-operative year.

In 15 patients the radiographs showed movement of the anterior metalwork, with broken or mobile screws or plates, and in six there were signs of a recurrent diastasis. In this group, four patients required revision surgery; three with anterior fixation and one with removal of anterior pelvic metalwork; the remaining 11 functioned as well as the rest of the study group.

We conclude that radiological signs of movement in the anterior pelvic metalwork, albeit common, are not in themselves an indication for revision surgery.
The combined effect of parathyroid hormone and bone graft on implant fixation
Authors: Daugaard H. , Elmengaard B. , Andreassen T. T. , Baas J. , Bechtold J. E. , Soballe K.
Published: January 2011

Impaction allograft is an established method of securing initial stability of an implant in arthroplasty. Subsequent bone integration can be prolonged, and the volume of allograft may not be maintained. Intermittent administration of parathyroid hormone has an anabolic effect on bone and may therefore improve integration of an implant.

Using a canine implant model we tested the hypothesis that administration of parathyroid hormone may improve osseointegration of implants surrounded by bone graft. In 20 dogs a cylindrical porous-coated titanium alloy implant was inserted into normal cancellous bone in the proximal humerus and surrounded by a circumferential gap of 2.5 mm. Morsellised allograft was impacted around the implant. Half of the animals were given daily injections of human parathyroid hormone (1–34) 5 μg/kg for four weeks and half received control injections. The two groups were compared by mechanical testing and histomorphometry. We observed a significant increase in new bone formation within the bone graft in the parathyroid hormone group. There were no significant differences in the volume of allograft, bone-implant contact or in the mechanical parameters.

These findings suggest that parathyroid hormone improves new bone formation in impacted morsellised allograft around an implant and retains the graft volume without significant resorption. Fixation of the implant was neither improved nor compromised at the final follow-up of four weeks.
Long-term results of tension-band laminoplasty for cervical stenotic myelopathy
Authors: Motosuneya T. , Maruyama T. , Yamada H. , Tsuzuki N. , Sakai H.
Published: January 2011

We reviewed 75 patients (57 men and 18 women), who had undergone tension-band laminoplasty for cervical spondylotic myelopathy (42 patients) or compression myelopathy due to ossification of the posterior longitudinal ligament (33 patients) and had been followed for more than ten years. Clinical and functional results were estimated using the Japanese Orthopaedic Association score. The rate of recovery and the level of postoperative axial neck pain were also recorded. The pre- and post-operative alignment of the cervical spine (Ishihara curve index indicating lordosis of the cervical spine) and the range of movement (ROM) of the cervical spine were also measured.

The mean rate of recovery of the Japanese Orthopaedic Association score at final follow-up was 52.1% (sd 24.6) and significant axial pain was reported by 19 patients (25.3%). Axial pain was reported more frequently in patients with ossification of the posterior longitudinal ligament than in those with cervical spondylotic myelopathy (p = 0.027). A kyphotic deformity was not seen post-operatively in any patient. The mean ROM decreased post-operatively from 32.8° (sd 12.3) to 16.2° (sd 12.3) (p < 0.001). The mean ROM ratio was 46.9% (sd 28.1) for all the patients. The mean ROM ratio was lower in patients with ossification of the posterior longitudinal ligament than in those with cervical spondylotic myelopathy (p < 0.001). Compared to those with cervical spondylotic myelopathy, patients with ossification of the posterior longitudinal ligament had less ROM and more post-operative axial neck pain.
Repair of spondylolysis using compression with a modular link and screws
Authors: Altaf F. , Osei N. A. , Garrido E. , Al-Mukhtar M. , Natali C. , Sivaraman A. , Noordeen H. H.
Published: January 2011

We describe the results of a prospective case series of patients with spondylolysis, evaluating a technique of direct stabilisation of the pars interarticularis with a construct that consists of a pair of pedicle screws connected by a U-shaped modular link passing beneath the spinous process. Tightening the link to the screws compresses bone graft in the defect in the pars, providing rigid intrasegmental fixation. We have carried out this procedure on 20 patients aged between nine and 21 years with a defect of the pars at L5, confirmed on CT. The mean age of the patients was 13.9 years (9 to 21). They had a grade I or less spondylolisthesis and no evidence of intervertebral degeneration on MRI. The mean follow-up was four years (2.3 to 7.3). The patients were assessed by the Oswestry Disability Index (ODI) and a visual analogue scale (VAS). At the latest follow-up, 18 patients had an excellent clinical outcome, with a significant (p < 0.001) improvement in their ODI and VAS scores. The mean ODI score at final follow-up was 8%. Assessment of the defect by CT showed a rate of union of 80%. There were no complications involving the internal fixation.

The strength of the construct removes the need for post-operative immobilisation.
High tibial osteotomy using polycaprolactone-tricalcium phosphate polymer wedge in a micro pig model
Authors: Lim H.-C. , Bae J.-H. , Song H.-R. , Teoh S. H. , Kim H.-K. , Kum D.-H.
Published: January 2011

Medial open-wedge high tibial osteotomy has been gaining popularity in recent years, but adequate supporting material is required in the osteotomy gap for early weight-bearing and rapid union. The purpose of this study was to investigate whether the implantation of a polycaprolactone-tricalcium phosphate composite scaffold wedge would enhance healing of the osteotomy in a micro pig model. We carried out open-wedge high tibial osteotomies in 12 micro pigs aged from 12 to 16 months. A scaffold wedge was inserted into six of the osteotomies while the other six were left open. Bone healing was evaluated after three and six months using plain radiographs, CT scans, measurement of the bone mineral density and histological examination.

Complete bone union was obtained at six months in both groups. There was no collapse at the osteotomy site, loss of correction or failure of fixation in either group. Staining with haematoxylin and eosin demonstrated that there was infiltration of new bone tissue into the macropores and along the periphery of the implanted scaffold in the scaffold group. The CT scans and measurement of the bone mineral density showed that at six months specimens in the scaffold group had a higher bone mineral density than in the control group, although the implantation of the polycaprolactone-tricalcium phosphate composite scaffold wedge did not enhance healing of the osteotomy.
Combined technique for the correction of lower-limb deformities resulting from metabolic bone disease
Authors: Kocaoglu M. , Bilen F. E. , Sen C. , Eralp L. , Balci H. I.
Published: January 2011

We present the results of the surgical correction of lower-limb deformities caused by metabolic bone disease. Our series consisted of 17 patients with a diagnosis of hypophosphataemic rickets and two with renal osteodystrophy; their mean age was 25.6 years (14 to 57). In all, 43 lower-limb segments (27 femora and 16 tibiae) were osteotomised and the deformity corrected using a monolateral external fixator. The segment was then stabilised with locked intramedullary nailing. In addition, six femora in three patients were subsequently lengthened by distraction osteogenesis. The mean follow-up was 60 months (18 to 120). The frontal alignment parameters (the mechanical axis deviation, the lateral distal femoral angle and the medial proximal tibial angle) and the sagittal alignment parameters (the posterior distal femoral angle and the posterior proximal tibial angle) improved post-operatively. The external fixator was removed either at the end of surgery or at the end of the lengthening period, allowing for early mobilisation and weight-bearing. We encountered five problems and four obstacles in the programme of treatment.

The use of intramedullary nails prevented recurrence of deformity and refracture.
Does the use of laminar flow and space suits reduce early deep infection after total hip and knee replacement?
Authors: Hooper G. J. , Rothwell A. G. , Frampton C. , Wyatt M. C.
Published: January 2011

We have investigated whether the use of laminar-flow theatres and space suits reduced the rate of revision for early deep infection after total hip (THR) and knee (TKR) replacement by reviewing the results of the New Zealand Joint Registry at ten years.

Of the 51 485 primary THRs and 36 826 primary TKRs analysed, laminar-flow theatres were used in 35.5% and space suits in 23.5%. For THR there was a significant increase in early infection in those procedures performed with the use of a space suit compared with those without (p < 0.0001), in those carried out in a laminar-flow theatre compared with a conventional theatre (p < 0.003) and in those undertaken in a laminar-flow theatre with a space suit (p < 0.001) when compared with conventional theatres without such a suit. The results were similar for TKR with the use of a space suit (p < 0.001), in laminar-flow theatres (p < 0.019) and when space suits were used in those theatres (p < 0.001). These findings were independent of age, disease and operating time and were unchanged when the surgeons and hospital were analysed individually.

The rate of revision for early deep infection has not been reduced by using laminar flow and space suits. Our results question the rationale for their increasing use in routine joint replacement, where the added cost to the health system seems to be unjustified.
In vitro study of the antimicrobial effects of radiological contrast agents used in arthrography
Authors: Bruins M. J. , Zwiers J. H. , Verheyen C. C. P. M. , Wolfhagen M. J. H. M.
Published: January 2011

Aspiration arthrography using an iodinated contrast medium is a useful tool for the investigation of septic or aseptic loosening of arthroplasties and of septic arthritis. Previously, the contrast media have been thought to cause false negative results in cultures when present in aspirated samples of synovial fluid, probably because free iodine is bactericidal, but reports have been inconclusive.

We examined the influence of the older, high osmolar contrast agents and the low osmolar media used currently on the growth of ten different micro-organisms capable of causing deep infection around a prosthesis. Five media were tested, using a disc diffusion technique and a time-killing curve method in which high and low inocula of micro-organisms were incubated in undiluted media. The only bactericidal effects were found with low inocula of Escherichia coli and Pseudomonas aeruginosa in ioxithalamate, one of the older ionic media.

The low and iso-osmolar iodinated contrast media used currently do not impede culture. Future study must assess other causes of false negative cultures of synovial fluid and new developments in enhancing microbial recovery from aspirated samples.
Systematic review and meta-analysis of the use of tranexamic acid in total hip replacement
Authors: Sukeik M. , Alshryda S. , Haddad F. S. , Mason J. M.
Published: January 2011

We report a systematic review and meta-analysis of published randomised controlled trials evaluating the efficacy of tranexamic acid (TXA) in reducing blood loss and transfusion in total hip replacement (THR). The data were evaluated using the generic evaluation tool designed by the Cochrane Bone, Joint and Muscle Trauma Group. We identified 11 clinical trials which were suitable for detailed extraction of data. There were no trials that used TXA in revision THR. A total of seven studies (comprising 350 patients) were eligible for the blood loss outcome data. The use of TXA reduced intra-operative blood loss by a mean of 104 ml (95% confidence interval (CI) −164 to −44, p = 0.0006, heterogeneity I2 0%), postoperative blood loss by a mean of 172 ml (95% CI −263 to −81, p = 0.0002, heterogeneity I2 63%) and total blood loss by a mean of 289 ml (95% CI −440 to −138, p < 0.0002, heterogeneity I2 54%).

TXA led to a significant reduction in the proportion of patients requiring allogeneic blood transfusion (risk difference −0.20, 95% CI −0.29 to −0.11, p < 0.00001, I2 15%). There were no significant differences in deep-vein thrombosis, pulmonary embolism, infection rates or other complications among the study groups.
Return to theatre following total hip and knee replacement, before and after the introduction of rivaroxaban
Authors: Jensen C. D. , Steval A. , Partington P. F. , Reed M. R. , Muller S. D.
Published: January 2011

Rivaroxaban has been recommended for routine use as a thromboprophylactic agent in patients undergoing lower-limb arthroplasty. However, trials supporting its use have not fully evaluated the risks of wound complications. This study of 1048 total hip/knee replacements records the rates of return to theatre and infection before and after the change from a low molecular weight heparin (tinzaparin) to rivaroxaban as the agent of chemical thromboprophylaxis in patients undergoing lower-limb arthroplasty. During a period of 13 months, 489 consecutive patients undergoing lower-limb arthroplasty received tinzaparin and the next 559 consecutive patients received rivaroxaban as thromboprophylaxis.

Nine patients in the control (tinzaparin) group (1.8%, 95% confidence interval 0.9 to 3.5) returned to theatre with wound complications within 30 days, compared with 22 patients in the rivaroxaban group (3.94%, 95% confidence interval 2.6 to 5.9). This increase was statistically significant (p = 0.046). The proportion of patients who returned to theatre and became infected remained similar (p = 0.10).

Our study demonstrates the need for further randomised controlled clinical trials to be conducted to assess the safety and efficacy of rivaroxaban in clinical practice, focusing on the surgical complications as well as the potential prevention of venous thromboembolism.
A shelf procedure at a follow-up of 75 years
Authors: Rajakulendran K. , Strambi F. , Buly J. , Field R. E.
Published: January 2011

Developmental dysplasia of the hip predisposes to premature degenerative hip disease. A number of operations have been described to improve acetabular cover and have achieved varying degrees of success. We present the case of an 84-year-old woman, who underwent a shelf procedure to reconstruct a dysplastic hip 75 years ago. To date, the shelf remains intact and the hip is asymptomatic. We believe this represents the longest documented outcome of any procedure to stabilise the hip.
Symptomatic pulmonary embolism after outpatient arthroscopic procedures of the knee
Authors: Hetsroni I. , Lyman S. , Do H. , Mann G. , Marx R. G.
Published: January 2011

Pulmonary embolism is a serious complication after arthroscopy of the knee, about which there is limited information. We have identified the incidence and risk factors for symptomatic pulmonary embolism after arthroscopic procedures on outpatients. The New York State Department of Health Statewide Planning and Research Cooperative System database was used to review arthroscopic procedures of the knee performed on outpatients between 1997 and 2006, and identify those admitted within 90 days of surgery with an associated diagnosis of pulmonary embolism. Potential risk factors included age, gender, complexity of surgery, operating time defined as the total time that the patient was actually in the operating room, history of cancer, comorbidities, and the type of anaesthesia. We identified 374 033 patients who underwent 418 323 outpatient arthroscopies of the knee. There were 117 events of pulmonary embolism (2.8 cases for every 10 000 arthroscopies). Logistic regression analysis showed that age and operating time had significant dose-response increases in risk (p < 0.001) for a subsequent admission with a pulmonary embolism. Female gender was associated with a 1.5-fold increase in risk (p = 0.03), and a history of cancer with a threefold increase (p = 0.05).

These risk factors can be used when obtaining informed consent before surgery, to elevate the level of clinical suspicion of pulmonary embolism in patients at risk, and to establish a rationale for prospective studies to test the clinical benefit of thromboprophylaxis in high-risk patients.
The instruments of the bonesetter
Authors: Phillips S.-A. , Biant L. C.
Published: January 2011

Orthopaedic surgeons use a variety of instruments to help correct, treat, and heal bone disease. The development of these instruments mirrors the history of orthopaedic surgery. The history of bonesetting, the treatment and replacement of joints, and of those who performed these techniques, appears to originate deep in antiquity. Changing ideas within medicine and surgery over the last 200 years have shaped the discovery and evolution of orthopaedic instruments and of the bonesetters themselves. Advances have led to the use of computers as instruments in the navigational guidance of arthroplasty surgery, the use of robotics, the development of cordless drills and improvements in the design of blades to cut bone. Yet some of the old instruments remain; plaster of Paris bandages, the Thomas Splint, Liston’s bonecutter, Gigli’s saw, bone nibblers and Macewan’s osteotomes are still in use.

This paper presents a historical review of bonesetters and examines how orthopaedic instruments have evolved from antiquity to the 21st century.
Proximal humeral fractures
Authors: Murray I. R. , Amin A. K. , White T. O. , Robinson C. M.
Published: January 2011

Most proximal humeral fractures are stable injuries of the ageing population, and can be successfully treated non-operatively. The management of the smaller number of more complex displaced fractures is more controversial and new fixation techniques have greatly increased the range of fractures that may benefit from surgery.

This article explores current concepts in the classification and clinical aspects of these injuries, reviewing the indications, innovations and outcomes for the most common methods of treatment.
Design and Characterization of a Theta-Pinch Imploding Thin Film Plasma Source for Atomic Emission Spectrochemical Analysis
Authors: Navarre Edward C. , Goldberg Joel M.
Published: January 2011

A new atomization device for direct atomic spectrochemical analysis has been developed that uses the theta-pinch configuration to generate a pulsed, high-energy-density plasma at atmospheric pressure. Energy from a 20-kV, 6.05-μF capacitive electrical discharge was inductively coupled to a sacrificial aluminum thin film to produce a cylindrical plasma. Current waveform analysis indicates an average power dissipation of 0.5 MW in the plasma. Electromagnetic modeling studies were used to identify theta-pinch designs possessing characteristics favorable to both plasma initiation and plasma heating. The discharge was most robust when the induced current and rate of magnetic field change were maximized. Minimizing the ratio of the coil's width to its radius was also critical. Counter to intuition, a larger diameter was found to be more successful. Spectroscopic studies indicate that the discharge forms a heterogeneous plasma with a dense, cylindrical plasma sheet confined by the walls of the discharge tube surrounding a less energetic plasma in the center. Al(II) emission in the outer plasma cylinder was temporally aligned with the induced current whereas in the center it aligns with the magnetic field. Ionization of support gas species (Ar, He, and air) was not observed, although the identity of the gas had a significant influence on the plasma reproducibility. The optimized design utilized a 5.5-turn, 19-mm-diameter theta coil with argon as the support gas. Sb(I) emission from an antimony oxide solid powder sample deposited on the thin film was observed primarily in the outer part of the plasma. Analyte emission shows contributions from magnetic compression early in the discharge and from the induced current late in the discharge. The discharge produced analytically useful signals from solid antimony oxide samples. Using spatially and temporally resolved detection, the line-to-background ratio for Sb(I) was found to be greater than 4 for emission integrated from 55 to 120 μs.
Assessing Phytoplankton Using a Two-Rank Database Based on Excitation-Emission Fluorescence Spectra
Authors: Zhang Fang , He Jiangfeng , Su Rongguo , Wang Xiulin
Published: January 2011

The feasibility of using a two-rank database of reference spectra based on in vivo fluorescence excitation-emission matrix (EEMs) spectra to assess dominant groups of phytoplankton was explored. Twenty-six species belonging to 20 genera of seven divisions were studied. First, fluorescent characteristics of these EEMs were extracted using Daubechies-7 wavelet analysis. Second, the optimal characteristic spectra of scale vectors (SOCS) and time-series vectors (TOCS) were selected; phytoplankton of different genera were classified using Fisher linear discriminant analysis. Third, SOCS and TOCS reference spectra databases were obtained by hierarchical cluster analysis. Using non-negative least squares as the method to assess the phytoplankton, a two-rank reference spectra database was established according to their respective ability to identify the 2818 single-species samples. Using this fluorimetric technique, the correct identification rates (CIRs) for single-species samples were 88.8–100% at the genus level and 98.8–100% at the division level. Dominant species in the 465 laboratory mixtures had corresponding CIRs of 85.6% and 96.1%. Moreover, 15 of the 19 species used as dominants were correctly identified at the genus level. In 27 natural seawater samples, Prorocentrum donghaiense, Thalassiosira nordenskioldi, and Chaetoceros socialis (bloom-forming species with a density of about 107 cell L−1), and Alexandrium sp. (dominant species with abundance of about 106 cell L−1) were qualitatively identified at the genus level; other dominant species, with densities of 105 to 106 cell L−1, were identified at the division level. The quantitative identification was relatively poor in the natural water samples, and several potential resolutions, including trying both new measuring methods and calculating methods, for future study are given.
A New Application of Fiber-Optic Reflection Spectroscopy (FORS): Characterization of Low-Temperature Alteration of Chlorite Schist and Implications for Understanding Ancient Stone Cooking Vessels
Authors: Namdar Dvory , Verri Giovanni , Stacey Rebecca J. , Middleton Andrew , Simpson St John
Published: January 2011

Bulk thermal alterations to chlorite schist occurring at temperatures above 450 °C are traditionally studied using X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, or thermogravimetric analysis (TGA), but lower temperature changes that lead to structural and chemical alteration, including changes in oxidation state that are not followed by a crystalline modification, are not detectable using these techniques. In this paper we present the results of the first study to examine the application of fiber-optic reflection spectroscopy (FORS) for the detection and quantification of low-temperature thermal alterations in chlorite schist. Such changes have been observed during research on the thermal behavior of medieval (12th–13th centuries AD) chlorite cooking pots from the archaeological site of Merv, Turkmenistan. FORS was used to investigate these changes, testing the archaeological samples against a model data set of experimental reference specimens. The results demonstrate the potential of FORS for tracking low-temperature thermal alterations and offer the opportunity to examine temperatures attained by ancient chlorite vessels during their past use in cooking activities.
A Model-Free, Fully Automated Baseline-Removal Method for Raman Spectra
Authors: Schulze H. Georg , Foist Rod B. , Okuda Kadek , Ivanov André , Turner Robin F. B.
Published: January 2011

We present here a fully automated spectral baseline-removal procedure. The method uses a large-window moving average to estimate the baseline; thus, it is a model-free approach with a peak-stripping method to remove spectral peaks. After processing, the baseline-corrected spectrum should yield a flat baseline and this endpoint can be verified with the χ2-statistic. The approach provides for multiple passes or iterations, based on a given χ2-statistic for convergence. If the baseline is acceptably flat given the χ2-statistic after the first pass at correction, the problem is solved. If not, the non-flat baseline (i.e., after the first effort or first pass at correction) should provide an indication of where the first pass caused too much or too little baseline to be subtracted. The second pass thus permits one to compensate for the errors incurred on the first pass. Thus, one can use a very large window so as to avoid affecting spectral peaks—even if the window is so large that the baseline is inaccurately removed—because baseline-correction errors can be assessed and compensated for on subsequent passes. We start with the largest possible window and gradually reduce it until acceptable baseline correction based on the χ2-statistic is achieved. Results, obtained on both simulated and measured Raman data, are presented and discussed.
Minor Distortions with Major Consequences: Correcting Distortions in Imaging Spectrographs
Authors: Esmonde-White Francis W. L. , Esmonde-White Karen A. , Morris Michael D.
Published: January 2011

Projective transformation is a mathematical correction (implemented in software) used in the remote imaging field to produce distortion-free images. We present the application of projective transformation to correct minor alignment and astigmatism distortions that are inherent in dispersive spectrographs. Patterned white-light images and neon emission spectra were used to produce registration points for the transformation. Raman transects collected on microscopy and fiber-optic systems were corrected using established methods and compared with the same transects corrected using the projective transformation. Even minor distortions have a significant effect on reproducibility and apparent fluorescence background complexity. Simulated Raman spectra were used to optimize the projective transformation algorithm. We demonstrate that the projective transformation reduced the apparent fluorescent background complexity and improved reproducibility of measured parameters of Raman spectra. Distortion correction using a projective transformation provides a major advantage in reducing the background fluorescence complexity even in instrumentation where slit-image distortions and camera rotation were minimized using manual or mechanical means. We expect these advantages should be readily applicable to other spectroscopic modalities using dispersive imaging spectrographs.
In situ Raman Monitoring of Competitive Adsorption of Ag and Au Nanoparticles onto a Poly(4-Vinyl Pyridine) Surface
Authors: Kim Kwan , Ryoo Hyunwoo , Shin Kuan Soo
Published: January 2011

The competitive adsorption of citrate-capped Ag and Au nanoparticles (∼25 nm in diameter) onto a poly(4-vinyl pyridine) (P4VP) surface has been investigated by means of Raman scattering spectroscopy. The P4VP film prepared on a glass slide was too thin for its normal Raman spectrum to be observed, but the Raman peaks of P4VP could be detected upon the adsorption of Ag and/or Au nanoparticles onto the film, due to the surface-enhanced Raman scattering (SERS) effect associated with the localized surface plasmon of Ag and/or Au nanoparticles. Neither quartz crystal microbalance nor atomic force microscopy (AFM) nor scanning electron microscopy (SEM) methodologies can distinguish between Ag and Au nanoparticles during their adsorption onto P4VP, but it is possible through Raman scattering spectroscopy because Ag (though not Au) nanoaggregates are SERS active at 514.5 nm excitation, while both Ag and Au nanoaggregates are SERS active at 632.8 nm excitation. Coupled with the AFM data, we were thus able to infer that about 120 Ag nanoparticles per 1 μm2 were adsorbed, along with 60 Au nanoparticles per 1 μm2, onto the P4VP film over a period of 1.5 h from a 1:1 mixture of Ag and Au sols at 1.6 nM each.