On-site treatment of avalanche victims: Scoping review and 2023 recommendations of the international commission for mountain emergency medicine (ICAR MedCom)

INTRODUCTION

The International Commission for Mountain Emergency Medicine (ICAR MedCom) developed updated recommendations for the management of avalanche victims.

METHODS

ICAR MedCom created Population Intervention Comparator Outcome (PICO) questions and conducted a scoping review of the literature. We evaluated and graded the evidence using the American College of Chest Physicians system.

RESULTS

We included 120 studies including original data in the qualitative synthesis. There were 45 retrospective studies (38%), 44 case reports or case series (37%), and 18 prospective studies on volunteers (15%). The main cause of death from avalanche burial was asphyxia (range of all studies 65-100%). Trauma was the second most common cause of death (5-29%). Hypothermia accounted for few deaths (0-4%).

CONCLUSIONS AND RECOMMENDATIONS

For a victim with a burial time ≤ 60 minutes without signs of life, presume asphyxia and provide rescue breaths as soon as possible, regardless of airway patency. For a victim with a burial time > 60 minutes, no signs of life but a patent airway or airway with unknown patency, presume that a primary hypothermic CA has occurred and initiate cardiopulmonary resuscitation (CPR) unless temperature can be measured to rule out hypothermic cardiac arrest. For a victim buried > 60 minutes without signs of life and with an obstructed airway, if core temperature cannot be measured, rescuers can presume asphyxia-induced CA, and should not initiate CPR. If core temperature can be measured, for a victim without signs of life, with a patent airway, and with a core temperature < 30 °C attempt resuscitation, regardless of burial duration.

Adipose-Derived Regenerative Cell Transplantation for the Treatment of Hand Dysfunction in Systemic Sclerosis: A Randomized Clinical Trial

Objective

Hand dysfunction is common in systemic sclerosis (SSc). We undertook this study to evaluate the capacity of autologous adipose‐derived regenerative cells (ADRCs) to improve hand function in SSc patients.

Methods

The Scleroderma Treatment with Celution Processed Adipose Derived Regenerative Cells Trial was a prospective, randomized, double‐blind trial of ADRCs, in which ADRCs were obtained from patients with SSc by small‐volume adipose tissue harvest, and the fingers of each patient were injected with ADRCs. The primary end point was change in hand function at 24 and 48 weeks, assessed using the Cochin Hand Function Scale (CHFS). One of the secondary end points included the change in Health Assessment Questionnaire disability index (HAQ DI) at 48 weeks. Separate prespecified analyses were performed for patients with diffuse cutaneous SSc (dcSSc) and those with limited cutaneous SSc (lcSSc).

Results

Eighty‐eight patients were randomized to receive ADRCs (n = 48 [32 patients with dcSSc and 16 with lcSSc]) or placebo (n = 40 [19 patients with dcSSc and 21 with lcSSc]). Change in hand function according to CHFS score was numerically higher for the ADRC group compared to the placebo group but did not achieve statistical significance (mean ± SD improvement in the CHFS score at 48 weeks 11.0 ± 12.5 versus 8.9 ± 10.5; P = 0.299). For patients with dcSSc, the between‐group difference in the CHFS at 48 weeks was 6.3 points (nominal P = 0.069). For the secondary end point, the dcSSc group exhibited a between‐group difference of 0.17 points in the HAQ DI (nominal P = 0.044) at 48 weeks. Of the ADRC‐treated patients with dcSSc, 52% reported improvement greater than the minimum clinically important difference for both CHFS and HAQ DI compared to 16% in the placebo group (nominal P = 0.016). Small‐volume adipose tissue harvest and ADRC treatment were well tolerated.

Conclusion

While the primary end point of this trial was not achieved, efficacy trends were observed in patients with dcSSc. Adipose tissue harvest and ADRC injection were demonstrated to be feasible. Further clinical trials of this intervention in the setting of dcSSc are warranted.

Providing Balanced Information about Options in Patient Decision Aids: An Update from the International Patient Decision Aid Standards

BACKGROUND

The objective of this International Patient Decision Aids Standard (IPDAS) review is to update and synthesize theoretical and empirical evidence on how balanced information can be presented and measured in patient decision aids (PtDAs).

METHODS

A multidisciplinary team conducted a scoping review using 2 search strategies in multiple electronic databases evaluating the ways investigators defined and measured the balance of information provided about options in PtDAs. The first strategy combined a search informed by the Cochrane Review of the Effectiveness of Decision Aids with a search on balanced information. The second strategy repeated the search published in the 2013 IPDAS update on balanced presentation.

RESULTS

Of 2450 unique citations reviewed, the full text of 168 articles was screened for eligibility. Sixty-four articles were included in the review, of which 13 provided definitions of balanced presentation, 8 evaluated mechanisms that may introduce bias, and 42 quantitatively measured balanced with methods consistent with the IPDAS criteria in PtDAs. The revised definition of balanced information is, "Objective, complete, salient, transparent, evidence-informed, and unbiased presentation of text and visual information about the condition and all relevant options (with important elements including the features, benefits, harms and procedures of those options) in a way that does not favor one option over another and enables individuals to focus attention on important elements and process this information."

CONCLUSIONS

Developers can increase the balance of information in PtDAs by informing their structure and design elements using the IPDAS checklist. We suggest that new PtDA components pertaining to balance be evaluated for cognitive bias with experimental methods as well by objectively evaluating patients' and content experts' beliefs from multiple perspectives.

Influence of an InGaN superlattice pre-layer on the performance of semi-polar (11-22) green LEDs grown on silicon

It is well-known that it is crucial to insert either a single InGaN underlayer or an InGaN superlattice (SLS) structure (both with low InN content) as a pre-layer prior to the growth of InGaN/GaN multiple quantum wells (MQWs) served as an active region for a light-emitting diode (LED). So far, this growth scheme has achieved a great success in the growth of III-nitride LEDs on c-plane substrates, but has not yet been applied in the growth of any other orientated III-nitride LEDs. In this paper, we have applied this growth scheme in the growth of semi-polar (11–22) green LEDs, and have investigated the impact of the SLS pre-layer on the optical performance of semi-polar (11–22) green LEDs grown on patterned (113) silicon substrates. Our results demonstrate that the semi-polar LEDs with the SLS pre-layer exhibit an improvement in both internal quantum efficiency and light output, which is similar to their c-plane counterparts. However, the performance improvement is not so significant as in the c-plane case. This is because the SLS pre-layer also introduces extra misfit dislocations for the semi-polar, but not the c-plane case, which act as non-radiative recombination centres.

Metrology of crystal defects through intensity variations in secondary electrons from the diffraction of primary electrons in a scanning electron microscope

Understanding defects and their roles in plastic deformation and device reliability is important for the development of a wide range of novel materials for the next generation of electronic and optoelectronic devices. We introduce the use of gaseous secondary electron detectors in a variable pressure scanning electron microscope for non-destructive imaging of extended defects using electron channelling contrast imaging. We demonstrate that all scattered electrons, including the secondary electrons, can provide diffraction contrast as long as the sample is positioned appropriately with respect to the incident electron beam. Extracting diffraction information through monitoring the modulation of the intensity of secondary electrons as a result of diffraction of the incident electron beam, opens up the possibility of performing low energy electron channelling contrast imaging to characterise low atomic weight and ultra-thin film materials. Our methodology can be adopted for large area, nanoscale structural characterisation of a wide range of crystalline materials including metals and semiconductors, and we illustrate this using the examples of aluminium nitride and gallium nitride. The capability of performing electron channelling contrast imaging, using the variable pressure mode, extends the application of this technique to insulators, which usually require conducting coatings on the sample surface for traditional scanning electron microscope based microstructural characterisation.

Determining GaN Nanowire Polarity and its Influence on Light Emission in the Scanning Electron Microscope

The crystal polarity of noncentrosymmetric wurtzite GaN nanowires is determined nondestructively in the scanning electron microscope using electron backscatter diffraction (EBSD). The impact of the nanowire polarity on light emission is then investigated using cathodoluminescence (CL) spectroscopy. EBSD can determine polarity of noncentrosymmetric crystals by interrogating differences in the intensity distribution of bands of the EBSD pattern associated with semipolar planes. Experimental EBSD patterns from an array of GaN nanowires are compared with theoretical patterns produced using dynamical electron simulations to reveal whether they are Ga- or N-polar or, as in several cases, of mixed polarity. CL spectroscopy demonstrates the effect of the polarity on light emission, with spectra obtained from nanowires of known polarity revealing a small but measurable shift (≈28 meV) in the GaN near band edge emission energy between those with Ga and N polarity. We attributed this energy shift to a difference in impurity incorporation in nanowires of different crystal polarity. This approach can be employed to nondestructively identify polarity in a wide range of noncentrosymmetric nanoscale material systems and provide direct comparison with their luminescence.

Monolithic multiple colour emission from InGaN grown on patterned non-polar GaN

A novel overgrowth approach has been developed in order to create a multiple-facet structure consisting of only non-polar and semi-polar GaN facets without involving any c-plane facets, allowing the major drawbacks of utilising c-plane GaN for the growth of III-nitride optoelectronics to be eliminated. Such a multiple-facet structure can be achieved by means of overgrowth on non-polar GaN micro-rod arrays on r-plane sapphire. InGaN multiple quantum wells (MQWs) are then grown on the multiple-facet templates. Due to the different efficiencies of indium incorporation on non-polar and semi-polar GaN facets, multiple-colour InGaN/GaN MQWs have been obtained. Photoluminescence (PL) measurements have demonstrated that the multiple-colour emissions with a tunable intensity ratio of different wavelength emissions can be achieved simply through controlling the overgrowth conditions. Detailed cathodoluminescence measurements and excitation-power dependent PL measurements have been performed, further validating the approach of employing the multiple facet templates for the growth of multiple colour InGaN/GaN MQWs. It is worth highlighting that the approach potentially paves the way for the growth of monolithic phosphor-free white emitters in the future.

Evolutionary and structural analyses uncover a role for solvent interactions in the diversification of cocoonases in butterflies

Multi-omic approaches promise to supply the power to detect genes underlying disease and fitness-related phenotypes. Optimal use of the resulting profusion of data requires detailed investigation of individual candidate genes, a challenging proposition. Here, we combine transcriptomic and genomic data with molecular modelling of candidate enzymes to characterize the evolutionary history and function of the serine protease cocoonase. Heliconius butterflies possess the unique ability to feed on pollen; recent work has identified cocoonase as a candidate gene in pollen digestion. Cocoonase was first described in moths, where it aids in eclosure from the cocoon and is present as a single copy gene. In heliconiine butterflies it is duplicated and highly expressed in the mouthparts of adults. At least six copies of cocoonase are present in Heliconius melpomene and copy number varies across H. melpomene sub-populations. Most cocoonase genes are under purifying selection, however branch-site analyses suggest cocoonase 3 genes may have evolved under episodic diversifying selection. Molecular modelling of cocoonase proteins and examination of their predicted structures revealed that the active site region of each type has a similar structure to trypsin, with the same predicted substrate specificity across types. Variation among heliconiine cocoonases instead lies in the outward-facing residues involved in solvent interaction. Thus, the neofunctionalization of cocoonase duplicates appears to have resulted from the need for these serine proteases to operate in diverse biochemical environments. We suggest that cocoonase may have played a buffering role in feeding during the diversification of Heliconius across the neotropics by enabling these butterflies to digest protein from a range of biochemical milieux.

Comparison of the Effects of a Pharmaceutical Industry Decision Guide and Decision Aids on Patient Choice to Intensify Therapy in Rheumatoid Arthritis

OBJECTIVE

To compare the effects a pharmaceutical industry decision guide and International Patient Decision Aids Standard (IPDAS) compliant patient decision aids (PtDA) on patient medication beliefs and choice to intensify therapy.

METHODS

Rheumatoid arthritis (RA) patients, who had never taken etanercept (Enbrel), took part in a mail survey. They were presented with a hypothetical decision scenario where they were asked to consider adding etanercept to their current regimen. Each patient was randomized to review 1 of 3 forms of an etanercept-specific decision support: a long PtDA (LONG DA), a short PtDA (SHORT DA), or the manufacturer's Enbrel decision guide (Pharm Booklet).

RESULTS

We had 402 RA patients participate in the study (response rate, 52%). Of the patients randomized to the Pharm Booklet, 30.6% elected to initiate etanercept. Only 14.6% and 14.0% of patients who reviewed the LONG DA or SHORT DA choose to take etanercept (χ2 = 15.7; P < 0.001). Patients who reviewed the LONG DA or SHORT DA had a greater increase in knowledge about etanercept than those who reviewed the Pharm Booklet. There was no difference in decisional conflict among the groups. A logistic regression model explained 44.2% (R2 = 0.442) of patient choice to intensify therapy by initiating etanercept. The strongest predictor of choice to intensify therapy were beliefs about etanercept's ability to improve symptoms (OR = 2.56, 96%CI [1.71, 3.80]), and its use by others like the respondent (OR = 2.24, 95%CI [1.49, 3.35]). Mediation analysis confirmed the presence of a partial mediating effect of decision support on patients' intent to take etanercept (OR = 0.59, 95%CI [0.39, 0.89]).

CONCLUSIONS

Patients supported by the Pharm Booklet were twice as likely to choose to intensify therapy. The Pharm Booklet's effects are partially mediated through persuasive communication techniques that influence patients' beliefs that symptoms will improve, and increase social normative beliefs, rather than by increasing the relevant knowledge, clarifying patient values about positive or negative treatment outcomes, or increasing their self-efficacy.

Safety, pharmacokinetics, and pharmacodynamics of RSLV-132, an RNase-Fc fusion protein in systemic lupus erythematosus: a randomized, double-blind, placebo-controlled study

Blood-borne RNA circulating in association with autoantibodies is a potent stimulator of interferon production and immune system activation. RSLV-132 is a novel fully human biologic Fc fusion protein that is comprised of human RNase fused to the Fc domain of human IgG1. The drug is designed to remain in circulation and digest extracellular RNA with the aim of preventing activation of the immune system via Toll-like receptors and the interferon pathway. The present study describes the first clinical study of nuclease therapy in 32 subjects with systemic lupus erythematosus. The drug was well tolerated with a very favorable safety profile. The approximately 19-day serum half-life potentially supports once monthly dosing. There were no subjects in the study that developed anti-RSLV-132 antibodies. Decreases in B-cell activating factor correlated with decreases in disease activity in a subset of patients.

Blood-Borne RNA Correlates with Disease Activity and IFN-Stimulated Gene Expression in Systemic Lupus Erythematosus

The loss of tolerance and the presence of circulating autoantibodies directed against nuclear Ags is the hallmark of systemic lupus erythematosus (SLE). Many of these Ags are complexed with short, noncoding RNAs, such as U1 and Y1. The amount of U1 and Y1 RNA complexed with SLE patient Abs and immune complexes was measured in a cross-section of 228 SLE patients to evaluate the role of these RNA molecules within the known biochemical framework of SLE. The study revealed that SLE patients had significantly elevated levels of circulating U1 and/or Y1 RNA compared with healthy volunteers. In addition, the blood-borne RNA molecules were correlated with SLE disease activity and increased expression of IFN-inducible genes. To our knowledge, this study provides the first systematic examination of the role of circulating RNA in a large group of SLE patients and provides an important link with IFN dysregulation.

Correction: Site controlled red-yellow-green light emitting InGaN quantum discs on nano-tipped GaN rods

Correction for 'Site controlled red-yellow-green light emitting InGaN quantum discs on nano-tipped GaN rods' by M. Conroy et al., Nanoscale, 2016, 8, 11019-11026.

Site controlled red-yellow-green light emitting InGaN quantum discs on nano-tipped GaN rods

We report a method of growing site controlled InGaN multiple quantum discs (QDs) at uniform wafer scale on coalescence free ultra-high density (>80%) nanorod templates by metal organic chemical vapour deposition (MOCVD). The dislocation and coalescence free nature of the GaN space filling nanorod arrays eliminates the well-known emission problems seen in InGaN based visible light sources that these types of crystallographic defects cause. Correlative scanning transmission electron microscopy (STEM), energy-dispersive X-ray (EDX) mapping and cathodoluminescence (CL) hyperspectral imaging illustrates the controlled site selection of the red, yellow and green (RYG) emission at these nano tips. This article reveals that the nanorod tips' broad emission in the RYG visible range is in fact achieved by manipulating the InGaN QD's confinement dimensions, rather than significantly increasing the In%. This article details the easily controlled method of manipulating the QDs dimensions producing high crystal quality InGaN without complicated growth conditions needed for strain relaxation and alloy compositional changes seen for bulk planar GaN templates.

Strong interband Faraday rotation in 3D topological insulator Bi2Se3

The Faraday effect is a representative magneto-optical phenomenon, resulting from the transfer of angular momentum between interacting light and matter in which time-reversal symmetry has been broken by an externally applied magnetic field. Here we report on the Faraday rotation induced in the prominent 3D topological insulator Bi₂Se₃ due to bulk interband excitations. The origin of this non-resonant effect, extraordinarily strong among other non-magnetic materials, is traced back to the specific Dirac-type Hamiltonian for Bi₂Se₃, which implies that electrons and holes in this material closely resemble relativistic particles with a non-zero rest mass.

Influence of patient characteristics on perceived risks and willingness to take a proposed anti-rheumatic drug

Background

The causes of the underutilization of disease modifying anti-rheumatic drugs (DMARDS) for rheumatoid arthritis (RA) are not fully known, but may in part, relate to individual patient factors including risk perception. Our objective was to identify the determinants of risk perception (RP) in RA patients and predictors of their willingness to take a proposed DMARD (DMARD willingness).

Methods

A cross-sectional mail survey of RA patients in a community rheumatology practice. Patients were presented a hypothetical decision scenario where they were asked to consider switching DMARDs. They evaluated how risky the proposed medication was and how likely they would be to take it.

Results

The completed sample included 1009 RA patients. The overall survey response rate was 71%. Patient characteristics: age 61.6 years (range 18-93), 75% female, minority 6.5%, low or marginal health literacy 8.8%, depression 15.0%, duration RA 13.1 years (range 0.5 – 68). Regression models demonstrated that health literacy, independent of low educational achievement or other demographic (including race), was a common predictor of both RP and DMARD willingness. There was partial mediation of the effects of HL on DMARD willingness through RP. Depression and happiness had no significant effect on RP or DMARD willingness. RP was influenced by negative RA disease and treatment experience, while DMARD willingness was affected mainly by perceived disease control.

Conclusions

Risk aversion may be the result of potentially recognizable and correctable cognitive defect. Heightened clinician awareness, formal screening for low health literacy or cognitive impairment in high-risk populations, may identify patients could benefit from additional decision support.

An experimental evaluation of patient decision aid design to communicate the effects of medications on the rate of progression of structural joint damage in rheumatoid arthritis

OBJECTIVE

To explore how effectively information presentation formats used in a patient decision aid communicated the ability of a disease modifying anti-rheumatic drug to slow the rate of progression of rheumatoid arthritis related structural joint damage (SJD).

METHODS

91 first year psychology students and 91 RA patients participated in a prospective randomized, single blind, factorial experimental design evaluating the effect of four information formats on: satisfaction with risk communication, verbatim and gist recall of a hypothetical anti-rheumatic drug's ability to slow the rate of progression of SJD.

RESULTS

Both groups underestimated the hypothetical drug's ability to slow SJD. Formats that supported the narrative statement with a reinforcing graphic element resulted in recall closer to the true value. Comparison of the results from testing of RA patients and college students were remarkably similar across formats.

CONCLUSION

Rate of progression as communicated by narrative statement plus a graphic element (i.e. speedometer metaphor or pictograph) aided recall better than a narrative statement alone. Our results suggest that testing decision aid components with non-patients may provide data generalizable to patient populations.

PRACTICE IMPLICATIONS

Graphics must be used carefully in patient decision aids as they can enhance recall, but may also introduce unintended recall bias.

Safety and efficacy of etanercept beyond 10 years of therapy in North American patients with early and longstanding rheumatoid arthritis

OBJECTIVE

To evaluate the long-term safety and efficacy of etanercept therapy in rheumatoid arthritis (RA) patients.

METHODS

Adult patients with early RA or longstanding RA received etanercept in open-label extension studies following initial double-blind trials of etanercept.

RESULTS

Of 558 early RA patients and 714 longstanding RA patients who received at least 1 dose of etanercept, a total of 194 early RA patients and 217 longstanding RA patients were treated with 25 mg of etanercept twice weekly through 10 years. Five opportunistic infections were reported: in early RA, 1 Candida septicemia; in longstanding RA, 1 herpes zoster, 1 atypical mycobacterium infection, 1 meningoencephalitis (unspecified), and 1 fungal sepsis (unspecified). Twenty-nine cases of sepsis occurred (10 early RA, 19 longstanding RA). Occurrence of all malignancies was similar to that expected in the general population, but the occurrence of lymphomas was higher than expected in the general population. Fourteen lymphomas (7 early RA, 7 longstanding RA) and 2 cases of demyelinating disease (1 early RA, 1 longstanding RA) were reported. Deaths occurred in 18 early RA patients and 43 longstanding RA patients. Both patient groups showed sustained improvement in American College of Rheumatology responses, swollen joint counts, Health Assessment Questionnaire disability index scores, and C-reactive protein levels.

CONCLUSION

Etanercept maintained therapeutic benefits beyond 10 years of therapy in both early RA and longstanding RA patients, suggesting that etanercept is well tolerated and effective as a long-term, continuous therapy for the treatment of RA, with a favorable risk/benefit ratio.

MQX-503, a novel formulation of nitroglycerin, improves the severity of Raynaud's phenomenon: a randomized, controlled trial

OBJECTIVE

Raynaud's phenomenon (RP) affects 3-9% of the general population and >90% of patients with systemic sclerosis. Nitrates are often prescribed for the treatment of RP, but currently available formulations are limited by side effects, particularly headaches, dizziness, and skin irritation. The purpose of this study was to evaluate the tolerability and efficacy of a novel formulation of topical nitroglycerin, MQX-503, in the treatment of RP in an ambulatory setting.

METHODS

We conducted a multicenter, randomized, placebo-controlled study with a 2-week single-blind run-in period to determine baseline severity, followed by a 4-week double-blind treatment phase. Two hundred nineteen adult patients with a clinical diagnosis of primary or secondary RP received 0.9% MQX-503 gel or matching placebo during the treatment period. Gel was applied immediately before or within 5 minutes of the beginning of an episode of RP (maximum of 4 applications daily). End points included the change in the mean Raynaud's Condition Score (RCS; scale 0-10), the frequency and duration of episodes, and subjective assessments at the target week (the week during the treatment phase that most closely matched the run-in period in terms of ambient temperature) compared with baseline.

RESULTS

The mean (%) change in the RCS at the target week compared with baseline was significantly greater in the MQX-503 group (0.48 [14.3%]) than that in the placebo group (0.04 [1.3%]; P = 0.04). Changes in the frequency and duration of RP episodes and subjective assessments were not statistically different between the groups. MQX-503 had a side effect profile similar to that of placebo.

CONCLUSION

MQX-503 is well tolerated and more effective than placebo for the treatment of RP.

The Yin and Yang of treating BRCA-deficient tumors

The myriad changes that occur during the malignant progression of cancer cells present challenges to both clinicians and basic scientists. Two new studies in Nature underscore the central role of genome instability in tumor biology (Edwards et al., 2008; Sakai et al., 2008). These reports describe secondary changes in the BRCA2 locus that restore the wild-type reading frame and contribute to the development of resistance to chemotherapeutic agents.

Patient decision-making related to antirheumatic drugs in rheumatoid arthritis: the importance of patient trust of physician

OBJECTIVE

To explore how rheumatoid arthritis (RA) antirheumatic drug-specific knowledge and numeric literacy, patient trust in physician, and demographic and disease-related factors relate to the confidence of patient decision-making related to disease modifying antirheumatic drugs (DMARD).

METHODS

Data were analyzed from 628 randomly selected patients with RA receiving care in community rheumatology practices, who responded to a multicenter, cross-sectional mail survey. We used multiple regression models to predict patient confidence in DMARD decision-making related to their most recently initiated DMARD.

RESULTS

Significant positive correlation was found between confidence in DMARD decision and trust in physician, DMARD-specific knowledge, and disease duration, but not risk-related numeric literacy, sex, or education. Negative correlations were found with disease severity and current bother with DMARD side effects. A multiple linear regression model of confidence in DMARD decision had an overall R = 0.788, R2 = 0.620 (p < 0.001). The 4 dependent variables contributing significantly to the model were female sex, Medicaid insurance status, satisfaction with RA disease control, and trust in physician, with standardized beta = 0.077, -0.089, 0.147, and 0.687, respectively.

CONCLUSION

In this sample of community patients with RA, the patient trust in physician had substantially greater effect on confidence in DMARD decision than DMARD-specific knowledge, disease-related factors, or demographic characteristics.

RAD51 up-regulation bypasses BRCA1 function and is a common feature of BRCA1-deficient breast tumors

The breast cancer susceptibility gene BRCA1 encodes a large protein thought to contribute to a variety of cellular processes, although the critical determinants of BRCA1-deficient tumorigenesis remain unclear. Given that BRCA1 is required for cell proliferation, suppressor mutations are believed to modify BRCA1 phenotypes and contribute to the etiology of BRCA1-deficient tumors. Here, we show that overexpression of the homologous recombinase RAD51 in a DT40 BRCA1Delta/Delta mutant rescues defects in proliferation, DNA damage survival, and homologous recombination (HR). In addition, epistasis analysis with BRCA1 and the DNA end-joining factor KU70 indicates that these factors operate independently of one another to repair double-strand breaks. Consistent with this genetic finding, cell synchronization studies show that the ability of BRCA1 to promote radioresistance is restricted to the late S and G2 phases of the cell cycle, as predicted for genes whose function is specific to homology-mediated repair rather than nonhomologous end-joining. Notably, retrospective analyses of microarray expression data reveal elevated expression of RAD51 and two of its late-acting cofactors, RAD54 and RAD51AP1, in BRCA1-deficient versus sporadic breast tumors. Taken together, our results indicate that up-regulation of HR provides a permissive genetic context for cells lacking BRCA1 function by circumventing its requirement in RAD51 subnuclear assembly. Furthermore, the data support a model in which enhanced HR activity contributes to the etiology of BRCA1-deficient tumors.

Brca1 in immunoglobulin gene conversion and somatic hypermutation

Defects in Brca1 confer susceptibility to breast cancer and genomic instability indicative of aberrant repair of DNA breaks. Brca1 was previously implicated in the homologous recombination pathway via effects on the assembly of recombinase Rad51. Activation-induced cytidine deaminase (AID) deaminates C to U in B lymphocyte immunoglobulin (Ig) DNA to initiate programmed DNA breaks. Subsequent uracil-glycosylase mediated U removal, and perhaps further processing, leads to four known classes of mutation: Ig class switch recombination that results in a region-specific genomic deletion, Ig somatic hypermutation that introduces point mutations in Ig V-regions, Ig gene conversion in vertebrates that possess Ig pseudo-V genes, and translocations common to B cell lymphomas. We tested the involvement of Brca1 in AID-dependent Ig diversification in chicken DT40 cells. The DT40 cell line diversifies IgVlambda mainly by gene conversion, and less so by point mutation. Brca1-deficiency caused a shift in Vlambda diversification, significantly reducing the proportion of gene conversions relative to point mutations. Thus, Brca1 regulates AID-dependent DNA lesion repair. Interestingly, while Brca1 is required to recruit ubiquitinated FancD2 to DNA damage, the phenotype of Brca1-deficient DT40 differs from the one of FancD2-deficient DT40, in which both gene conversion and non-templated mutations are impaired.

Multipole shimming of permanent magnets using harmonic corrector rings

Shimming systems are required to provide sufficient field homogeneity for high resolution nuclear magnetic resonance (NMR). In certain specialized applications, such as rotating-field NMR and mobile ex situ NMR, permanent magnet-based shimming systems can provide considerable advantages. We present a simple two-dimensional shimming method based on harmonic corrector rings which can provide arbitrary multipole order shimming corrections. Results demonstrate, for example, that quadrupolar order shimming improves the linewidth by up to an order of magnitude. An additional order of magnitude reduction is in principle achievable by utilizing this shimming method for z-gradient correction and higher order xy gradients.

Outcome measurements in scleroderma: results from a delphi exercise

OBJECTIVE

To obtain a consensus on the minimal clinically relevant treatment effect in various scleroderma disease outcome measures to be used in future clinical trials.

METHODS

A Delphi consensus building exercise using a survey was sent out to members of the Scleroderma Clinical Trials Consortium (SCTC). The 65 SCTC members were divided into 2 groups. Group 1 was informed, in a cover letter, of the usual American College of Rheumatology 20% response results in randomized trials using effective biologic treatments for rheumatoid arthritis, while Group 2 was not. The first round of the exercise presented the scleroderma experts with a survey composed of 95 questions/clinical scenarios divided into 8 categories. These included situations where the treatment group improved, or worsened, or where some outcome measures improved, while others worsened. From the responses of this first round, a mean, mode, median, and range of responses for each of the 95 questions was obtained. This information was sent out, in the second round of the Delphi exercise, only to those respondents who answered the first round. The respondent's previous answer and the mean and range from the first round were provided for each question. It gave respondents the option to change any of their initial responses. The median of their responses in the second round was used to calculate the values for the minimal clinically relevant treatment effect.

RESULTS

Thirty-two of the 65 SCTC members returned the first round of the Delphi exercise. Twenty-eight members returned the second round. Intraclass correlation coefficients between responses to round 1 and 2 were calculated for the questions. These varied from 0.99 (excellent agreement) to 0.02 (poor agreement). The p value was under 0.09 for 9 questions and under 0.19 for 20 questions. Standard deviations (SD) were calculated and were found to be lesser for each of the questions in round 2 when compared to the SD in responses from round 1, thus indicating a movement towards a consensus by the second round. An average of 33% of the responses were changed by the respondents in the second round of the Delphi exercise to a value closer to the median/average of the first round's responses. A range in required values for the minimal clinically relevant treatment effect for Modified Rodnan skin score is 3 to 7.5 units, Health Assessment Questionnaire Disability Index (HAQ-DI) 0.2 to 0.25 units, HAQ pain 0.2 to 0.3 units, MD global (100 mm visual analog scale) 8 to 13, patient global assessment 10 to 12, and diffusing capacity (percentage predicted) 9 to 10. The scenarios were especially weighted towards overall disease modification, thus organ-specific measures, such as 6 minute walk time (which has been used in many pulmonary artery hypertension trials), forced vital capacity, and a dyspnea rating (which may be important in scleroderma lung trials), were not included in the survey.

CONCLUSION

Our study begins to address the current deficiency in our knowledge of appropriate values for the minimal clinically relevant treatment effect in various scleroderma disease outcome measures. A consensus could be achieved, or at least a range of minimal clinically relevant treatment effect values could be found for several outcome measurements. Of course, this consensus statement will be modified by evidence as it accrues in each consensus area.

Anomalous ion channeling in AlInN/GaN bilayers: determination of the strain state

Monte Carlo simulations of anomalous ion channeling in near-lattice-matched AlInN/GaN bilayers allow an accurate determination of the strain state of AlInN by Rutherford backscattering or channeling. Although these strain estimates agree well with x-ray diffraction (XRD) results, XRD composition estimates are shown to have limited accuracy, due to a possible deviation from Vegard's law, which we quantify for this alloy. As the InN fraction increases from 13% to 19%, the strain in AlInN films changes from tensile to compressive with lattice matching predicted to occur at [InN] = 17.1%.

Etanercept treatment in adults with established rheumatoid arthritis: 7 years of clinical experience

OBJECTIVE

To evaluate safety and efficacy of longterm etanercept treatment in patients with disease modifying antirheumatic drug (DMARD) refractory rheumatoid arthritis (RA).

METHODS

Safety results are reported for 714 patients who received etanercept in one of 7 initial trials or a longterm extension. Efficacy results are reported for 581 patients who enrolled in the extension.

RESULTS

Of the 714 patients enrolled in the initial trials, 581 (81%) enrolled in the extension, and 388 (54%) patients are continuing to receive etanercept therapy. The longest individual treatment was 8.2 years, with 3139 total patient-years of etanercept exposure. Rates of serious adverse events (overall rate=14.8 events/100 patient-yrs), serious infections (overall rate=4.2 events/100 patient-yrs), cancer (overall rate=1.0 events/100 patient-yrs), and deaths (overall rate=0.7 events/100 patient-yrs) were stable each year, through 8 years of etanercept exposure. For 356 patients who completed 6 years of etanercept treatment, response rates were ACR20=73%, ACR50=52%, ACR70=27%, DAS28 CRP good response=52%, and DAS28 CRP remission=37% of patients. Similar responses occurred in 167 patients who completed Year 7. Doses of concomitant methotrexate or corticosteroids were reduced in many patients who maintained clinical responses.

CONCLUSION

The safety profile of etanercept was consistent over time, with rates of adverse events similar to those reported for patients with RA in general. Durable clinical responses were observed in some patients for 7 years or more. The benefit-to-risk ratio for longterm etanercept treatment remains highly favorable.

Minimally important difference in diffuse systemic sclerosis: results from the D-penicillamine study

OBJECTIVE

To estimate minimally important differences (MIDs) in scores for the modified Rodnan Skin Score (mRSS) and Health Assessment Questionnaire-Disability Index (HAQ-DI) in a clinical trial on diffuse systemic sclerosis (SSc).

PARTICIPANTS AND METHODS

134 people participated in a 2-year, double-blind, randomised clinical trial comparing efficacy of low-dose and high-dose D-penicillamine in diffuse SSc. At 6, 12, 18 and 24 months, the investigator was asked to rate the change in the patient's health since entering the study: markedly worsened, moderately worsened, slightly worsened, unchanged, slightly improved, moderately improved or markedly improved. Patients who were rated as slightly improved were defined as the minimally changed subgroup and compared with patients rated as moderately or markedly improved.

RESULTS

The MID estimates for the mRSS improvement ranged from 3.2 to 5.3 (0.40-0.66 effect size) and for the HAQ-DI from 0.10 to 0.14 (0.15-0.21 effect size). Patients who were rated to improve more than slightly were found to improve by 6.9-14.2 (0.86-1.77 effect size) on the mRSS and 0.21-0.55 (0.32-0.83 effect size) on the HAQ-DI score.

CONCLUSION

MID estimates are provided for improvement in the mRSS and HAQ-DI scores, which can help in interpreting clinical trials on patients with SSc and be used for sample size calculation for future clinical trials on diffuse SSc.

Targeted disruption of Mig-6 in the mouse genome leads to early onset degenerative joint disease

Degenerative joint disease, also known as osteoarthritis, is the most common joint disorder in human beings. The molecular mechanism underlying this disease is not fully understood. Here, we report that disruption of mitogen-inducible gene 6 (Mig-6) in mice by homologous recombination leads to early onset degenerative joint disease, which is revealed by simultaneous enlargement and deformity of multiple joints, degradation of articular cartilage, and the development of bony outgrowths or osteophyte formation within joint space. The osteophyte formation appears to be derived from proliferation of mesenchymal progenitor cells followed by differentiation into chondrocytes. Absence of the Rag2 gene does not rescue the joint phenotype, excluding a role for the acquired immune system in the development of this disease. Our results provide insight into the mechanism of osteoarthritis by showing that loss of Mig-6 leads to early onset of this disease, implying that this gene or its pathway is important in normal joint maintenance. Because of the striking similarity of osteoarthritis in humans and mice, the Mig-6 mutant mouse should provide a useful animal model for studying the mechanism of this disease and for testing drugs or therapies for treating osteoarthritis.

Longterm safety, efficacy, and radiographic outcome with etanercept treatment in patients with early rheumatoid arthritis

OBJECTIVE

To evaluate safety, efficacy, and radiographic progression in patients with early rheumatoid arthritis (RA) undergoing longterm treatment with etanercept.

METHODS

Patients with early RA (disease duration of 3 years or less) who had completed a 2-year efficacy study comparing etanercept and methotrexate (MTX) were followed in an extension where they received 25 mg etanercept twice weekly. Safety was summarized descriptively and compared with data from the efficacy study. Efficacy and radiographic progression were assessed using American College of Rheumatology response criteria, disease activity scores, and Total Sharp Score (TSS).

RESULTS

Rates of serious adverse events and serious infections did not increase with longterm exposure to etanercept, and were similar to rates reported for the blinded portion of the efficacy study. Efficacy was sustained in patients who completed 5 years of etanercept treatment at the time of this report (N = 201), even in those who decreased or discontinued use of MTX or corticosteroids. No radiographic progression (change in TSS < or = 0) was seen in 55% of patients with 5-year radiographs; negative change (TSS < 0) was seen in 11%.

CONCLUSION

Etanercept treatment in patients with early RA was generally well tolerated for up to 5 years. The results indicate sustained efficacy and decreased rate of radiographic progression. The rate of radiographic progression was low compared with other studies, emphasizing the benefit gained in patients with early aggressive RA who undergo longterm treatment with etanercept.

Pneumococcal vaccine response in psoriatic arthritis patients during treatment with etanercept

OBJECTIVE

Therapeutics used to treat inflammatory diseases, including psoriatic arthritis (PsA), may potentially interfere with normal immune system function. Immune system function can be assessed by evaluating response to vaccination. We assessed the ability of patients with PsA treated with etanercept to produce antibodies in response to pneumococcal antigen challenge.

METHODS

Patients with PsA (n = 205) were stratified by methotrexate (MTX) use and randomly assigned to receive either placebo or etanercept 25 mg twice weekly by subcutaneous injection. After 4 weeks of treatment with study drug, a 23-valent pneumococcal vaccination was administered. Antibody levels to 5 antigens (9V, 14, 18C, 19F, and 23F) were measured by ELISA before and 4 weeks after vaccination in 184 patients. The proportion (%) of patients with 2- and 4-fold increases in antibody titers was analyzed.

RESULTS

Patients treated with etanercept or placebo had similar responses to the vaccine. A 2-fold increase in titer to at least 2 antigens was achieved by 67% of patients, and a 4-fold increase to at least 2 antigens was achieved by 47% of patients. Approximately 20% of patients in each group failed to show a 2-fold response to any antigens. Logistic regression analysis showed MTX use and age were predictors of a poor response.

CONCLUSIONS

Patients with PsA treated with etanercept were able to produce antibodies in response to pneumococcal vaccination. Patients receiving MTX had lower mean antibody levels in response to the vaccine. There was no increased risk of poor response with etanercept treatment given alone or with MTX.

Adjunctive antibiotic treatment of women with preterm rupture of membranes or preterm labor

Subclinical infection is associated with preterm rupture of the membranes (PROM) and preterm labor (PTL) in many cases. It was hypothesized that antibiotic treatment might delay delivery and/or decrease infectious morbidity in those with PROM or PTL. Patients from 19 to 34 weeks with PROM and no labor or PTL with intact membranes (but not both) were separately randomized to receive ampicillin versus placebo in addition to usual therapy. There were 36 women with PTL (21 ampicillin/15 placebo) and 84 with preterm PROM (41 ampicillin/43 placebo). Demographically, the treatment and placebo groups were similar. Outcome variables analyzed included delivery delay after treatment, maternal chorioamnionitis/endometritis, Apgar score, neonatal infection, or respiratory distress, and hospital stay. There were no significant differences between the ampicillin and placebo groups in those with PTL or preterm PROM as it concerned outcome parameters. Adjunctive ampicillin used for treatment of idiopathic PTL or preterm PROM was not beneficial in this study.

High-dose versus low-dose ?-penicillamine in early diffuse systemic sclerosis trial: lessons learned

OBJECTIVES

To review important findings, or lessons, that were learned about measures of response, design, conduct, and analysis of a randomized, controlled trial (RCT), even though the trial failed to demonstrate efficacy of d-penicillamine.

METHODS

One hundred thirty-four patients with early (< or =18 months), diffuse systemic sclerosis (SSc) were entered into an RCT (high-dose [822 mg daily] vs low-dose [120 mg every other day] D-penicillamine) and were followed up regularly for up to 4 years. Because analysis failed to show efficacy for D-penicillamine in early diffuse SSc, all data were pooled for additional secondary analyses.

RESULTS

This RCT showed that trials of potential disease-modifying interventions can be completed in SSc using the American College of Rheumatology guidelines. This RCT used an active control. After analysis, we were not able to tell whether either dose was effective or ineffective. That experience argues in favor of using placebo controls until such time as an active control can be found that truly modifies the disease. Skin score and the disability index of the Health Assessment Questionnaire (HAQ-DI) were valid predictors of outcome. Along with the physician global assessment, they also were valid measures of response.

CONCLUSIONS

Even in studies that are therapeutically "negative," careful evaluation of the data can examine other hypotheses and thereby provide important insights into other aspects of trial design, outcome measures, patient function, and trial conduct.

Local surface skimming longitudinal wave velocity and residual stress mapping

Local variation in surface skimming longitudinal wave (SSLW) velocity has been measured using a scanning acoustic microscope. A very narrow width electrical impulse has been used to excite the transducer of the acoustic lens. This permits the separation of the SSLW signal from the direct reflected signal in the time domain. A simple method of measuring the time delay between the directly reflected signal and the SSLW signal at two defocuses has been utilized for the local measurement of SSLW velocity. The variation in the SSLW velocity measured over an area of the sample is scaled and presented as an image. The method has been implemented to image the variation of the SSLW velocity around a crack tip in a sample of Ti-6Al-4V. Since the SSLW velocity is known to change linearly with the stress, the SSLW velocity image is considered as a representation of the image of stress around the crack tip. Local stress variation in the same region of the crack tip is directly measured using x-ray diffraction. The SSLW velocity image is compared with the x-ray diffraction stress image. The contrast in the two images, spatial resolution, and the penetration depth into the sample of acoustic waves and x rays are discussed.

Response to etanercept (Enbrel) in elderly patients with rheumatoid arthritis: a retrospective analysis of clinical trial results

OBJECTIVE

Approximately 3% of the US population over the age of 65 years has rheumatoid arthritis (RA). We compared the safety and efficacy of etanercept (Enbrel) in patients with RA who were > or = 65 years to those < 65 years in open-label and double-blind, randomized clinical trials.

METHODS

Patients from 4 double-blind, randomized controlled trials and 5 open-label trials were included in this retrospective analysis. Patients were grouped by age (< 65 or > or = 65 yrs) at time of study entry. All patients received etanercept subcutaneously twice weekly. Improvement in signs and symptoms was assessed by the proportion of patients who achieved the American College of Rheumatology definition of improvement (ACR 20). The ACR 50 and ACR 70 responses were calculated in an analogous fashion. Safety was assessed at regularly scheduled visits.

RESULTS

Of 1128 patients enrolled in etanercept trials, 197 (17%) were > or = 65 years of age. Clinical response was rapid and sustained and did not differ between age groups. At one year, 69% of patients < 65 years and 66% of patients > or = 65 years met the ACR 20. Forty percent of the patients > or = 65 years met the ACR 50 and 17% met the ACR 70. Etanercept was well tolerated. Although injection site reactions, headache, and rhinitis occurred somewhat more frequently in younger patients, the overall rates and types of other adverse events were comparable in both groups.

CONCLUSION

Etanercept is a new treatment option for older patients with RA and has substantial benefit and comparable safety regardless of patient age.

Predictors and outcomes of scleroderma renal crisis: the high-dose versus low-dose D-penicillamine in early diffuse systemic sclerosis trial

OBJECTIVE

The reported frequency of scleroderma M01-R renal crisis (SRC) in diffuse systemic sclerosis (SSc; scleroderma) is 15-20%. Early use of angiotensin-converting enzyme (ACE) inhibitors has markedly improved outcome. The present analysis reexamines the prognostic factors for and outcome of SRC in a prospective cohort of patients with early diffuse SSc.

METHODS

We retrospectively evaluated the cohort of SSc patients who participated in the High-Dose Versus Low-Dose D-Penicillamine in Early Diffuse SSc trial. Patients with diffuse cutaneous scleroderma were enrolled if their disease duration was <18 months. Because the trial failed to show a difference between treatment groups, the data were pooled.

RESULTS

One hundred thirty-four SSc patients entered the observation period a mean +/- SD of 0.8 +/- 0.3 years after onset of SSc. SRC occurred in 18 patients a mean +/- SD of 0.9 +/- 1.1 years after entry. During a mean +/- SD 4.0 +/- 1.1 years of followup after entry, 9 of the 18 patients died (mean +/- SD 0.6 +/- 0.9 years after SRC onset). Baseline characteristics that predicted SRC included a modified Rodnan skin thickness score of >or=20 (P < 0.01), enlarged cardiac silhouette on radiograph (P = 0.04), large joint contractures (wrist, elbow, knee) (P = 0.008), and prednisone use at entry (P = 0.01). Baseline characteristics that did not predict SRC included age, sex, race, Health Assessment Questionnaire score, fist closure, handspread, lung involvement, muscle weakness, erythrocyte sedimentation rate, and platelet count. In 5 of 10 subjects for whom at least 2 sequential skin scores were available, skin scores increased significantly (P = 0.012) in the 6 months before onset of SRC.

CONCLUSION

SRC occurred in 13% of patients soon (mean 11 months) after entry into the cohort. Predictors of SRC identified in this study included higher than average skin score, prednisone use at study entry, large joint contractures, and heart enlargement. Our data suggest, however, that low-dose prednisone alone was not associated with the onset of SRC, except in the appropriate clinical setting. Although ACE inhibitors and dialysis are now readily available, SRC continues to be associated with poor survival (in this study, 50% of patients with SRC died).

Measuring disease activity and functional status in patients with scleroderma and Raynaud's phenomenon

OBJECTIVE

To document disease activity and functional status in patients with scleroderma (systemic sclerosis [SSc]) and Raynaud's phenomenon (RP) and to determine the sensitivity to change, reliability, ease of use, and validity of various outcome measures in these patients.

METHODS

Patients with SSc and moderate-to-severe RP participating in a multicenter RP treatment trial completed daily diaries documenting the frequency and duration of RP attacks and recorded a daily Raynaud's Condition Score (RCS). Mean scores for the 2-week periods prior to baseline (week 0), end of trial (week 6), and posttrial followup (week 12) were calculated. At weeks 0, 6, and 12, physicians completed 3 global assessment scales and performed clinical assessments of digital ulcers and infarcts; patients completed the Health Assessment Questionnaire (HAQ), the Arthritis Impact Measurement Scales 2 (AIMS2) mood and tension subscales, 5 specific SSc/RP-related visual analog scales (VAS), and 3 other VAS global assessments. We used these measures to document baseline disease activity and to assess their construct validity, sensitivity to change, and reliability in trial data.

RESULTS

Two hundred eighty-one patients (248 women, 33 men; mean age 50.4 years [range 18-82 years]) from 14 centers participated. Forty-eight percent had limited cutaneous SSc; 52% had diffuse cutaneous SSc. Fifty-nine patients (21%) had digital ulcers at baseline. Patients had 3.89 +/- 2.33 (mean +/- SD) daily RP attacks (range 0.8-14.6), with a duration of 82.1 +/- 91.6 minutes/attack. RCS for RP activity (possible range 0-10) was 4.30 +/- 1.92. HAQ scores (0-3 scale) indicated substantial disability at baseline (total disability 0.86, pain 1.19), especially among the subscales pertaining to hand function (grip, eating, dressing). AIMS2 mood and tension scores were fairly high, as were many of the VAS scores. Patients with digital ulcers had worse RCS, pain, HAQ disability (overall, grip, eating, and dressing), physician's global assessment, and tension, but no significant difference in the frequency of RP, duration of RP, patient's global assessment, or mood, compared with patients without digital ulcers. VAS scores for digital ulcers as rated by the patients were not consistent with the physician's ratings. Factor analysis of the 18 measures showed strong associations among variables in 4 distinct domains: disease activity, RP measures, digital ulcer measures, and mood/tension. Reliability of the RCS, HAQ pain and disability scales, and AIMS2 mood and tension subscales was high. The RP measures demonstrated good sensitivity to change (effect sizes 0.33-0.76).

CONCLUSION

Our findings demonstrate that the significant activity, disability, pain, and psychological impact of RP and digital ulcers in SSc can be measured by a small set of valid and reliable outcome measures. These outcome measures provide information beyond the quantitative metrics of RP attacks. We propose a core set of measures for use in clinical trials of RP in SSc patients that includes the RCS, patient and physician VAS ratings of RP activity, a digital ulcer/infarct measure, measures of disability and pain (HAQ), and measures of psychological function (AIMS2).

Etanercept versus methotrexate in patients with early rheumatoid arthritis: two-year radiographic and clinical outcomes

OBJECTIVE

To compare the clinical and radiographic outcomes in patients with rheumatoid arthritis (RA) who received monotherapy with either etanercept or methotrexate (MTX) for 2 years and to assess the safety of this therapy.

METHODS

In the Enbrel ERA (early rheumatoid arthritis) trial, 632 patients with early, active RA were randomized to receive either twice-weekly subcutaneous etanercept (10 mg or 25 mg) or weekly oral MTX (mean dosage 19 mg per week) for at least 1 year in a double-blind manner. Following the blinded phase of the trial, 512 patients continued to receive the therapy to which they had been randomized for up to 1 additional year, in an open-label manner. Radiograph readers remained blinded to treatment group assignment and the chronologic order of images.

RESULTS

At 24 months, more 25-mg etanercept patients than MTX patients met American College of Rheumatology 20% improvement criteria (72% and 59%, respectively; P = 0.005), and more had no increase in total score and erosion scores on the Sharp scale (P = 0.017 and P = 0.012, respectively). The mean changes in total Sharp score and erosion score in the 25-mg etanercept group (1.3 and 0.66 units, respectively) were significantly lower than those in the MTX group (3.2 and 1.86 units, respectively; P = 0.001). Significantly more patients in the 25-mg etanercept group (55%) than in the MTX group (37%) had at least 0.5 units of improvement in the Health Assessment Questionnaire disability index (P < 0.001). Fewer patients in the etanercept group than in the MTX group experienced adverse events or discontinued treatment because of adverse events.

CONCLUSION

Etanercept as monotherapy was safe and was superior to MTX in reducing disease activity, arresting structural damage, and decreasing disability over 2 years in patients with early, aggressive RA.

Quantitative imaging of Rayleigh wave velocity with a scanning acoustic microscope

An acoustic microscope operating with impulse excitation has been used to perform measurements of the Rayleigh wave velocity by measuring the time difference between the direct reflected signal and the Rayleigh wave signal. The accuracy and precision of the methodology have been examined by performing measurements at a single location on an elastically isotropic sample of E6 glass. The accuracy of the Rayleigh wave velocity measurement has been determined to be better than 0.5%. The measured Rayleigh wave velocity of (3035+/-5) m/s differs by 0.3% from measurements reported in the literature for a similar sample, using two different techniques. The methodology has been extended to acquire the Rayleigh wave velocity while raster scanning the sample to develop a quantitative velocity image. The background noise in the Rayleigh wave velocity image has been investigated by mapping the velocity on elastically isotropic E6 glass. Possible reasons for background noise in the images is discussed. The methodology has been extended to acquire quantitative Rayleigh wave velocity images on Ti-6Al-4V. The contrast in the images is attributed to the variation of the Rayleigh wave velocity in individual grains or regions. Applicability of the technique to investigate crystallographic texture in materials is discussed.

The myth of transient hypertension: descriptor or disease process?

The objective of this study is to describe the incidence of transient hypertension and to evaluate if transient hypertension is associated with increased maternal or fetal morbidity as compared to other hypertensive disorders of pregnancy and normotensive controls. Data were collected from all deliveries at the University of Mississippi Medical Center from July 1, 1996 through January 1, 1997. Patients were grouped according to ACOG criteria for pregnancy induced hypertension. Specific maternal and fetal morbidities were compared among the groups and controls. There were 1489 deliveries during the study period. Nearly 30% of patients met the criteria for transient hypertension. There were no significant differences between patients with transient hypertension and controls in regard to maternal and fetal outcomes. Transient hypertension occurs more often than expected, however, it appears to be of limited clinical significance.

Color Doppler detection of acoustic streaming in a hematoma model

Accurate differentiation between stagnant blood and soft tissue or clotted and unclotted blood has potential value in managing trauma patients with internal hemorrhage. Determination by regular ultrasound (US) imaging is sometimes difficult because the sonographic appearance of blood, clots and soft tissue may be similar. A hematoma model was developed to investigate the use of acoustic streaming for hematoma diagnosis in an in vivo environment. The results showed that a derated spatial peak temporal average (SPTA) intensity of 30 W/cm(2) was needed to generate color-Doppler-detectable streaming in stirred blood. The streaming velocity increased in proportion to the derated intensity. Streaming was also detected in stagnant blood, but at higher intensities. In clots, streaming was not detected even at high intensities. The streaming detection may be a valuable tool for improving the distinction between liquid blood and clots or soft tissue in hematoma diagnosis.

Quantification of gastric emptying and duodenogastric reflux stroke volumes using three-dimensional guided digital color Doppler imaging

OBJECTIVE

To develop a non-invasive method for evaluating gastric emptying and duodenogastric reflux stroke volumes using three-dimensional (3D) guided digital color Doppler imaging.

METHODS

The technique involved color Doppler digital images of transpyloric flow in which the 3D position and orientation of the images were known by using a magnetic location system.

RESULTS

In vitro, the system was found to slightly underestimate the reference flow (by average 8.8%). In vivo (five volunteers), stroke volume of gastric emptying episodes lasted on average only 0.69 s with a volume on average of 4.3 ml (range 1.1-7.4 ml), and duodenogastric reflux episodes on average 1.4 s with a volume of 8.3 ml (range 1.3-14.1 ml).

CONCLUSION

With the appropriate instrument settings, orientation determined color Doppler can be used for stroke volume quantification of gastric emptying and duodenogastric reflux episodes.

A new high intensity focused ultrasound applicator for surgical applications

Improved high-intensity focused ultrasound (HIFU) surgical applicators are required for use in a surgical environment. We report on the performance and characteristics of a new solid-cone HIFU applicator. Previous HIFU devices used a water-filled stand-off to couple the ultrasonic energy from the transducer to the treatment area. The new applicator uses a spherically-focused element and a solid aluminum cone to guide and couple the ultrasound to the tissue. Compared with the water-filled applicators, this new applicator is simpler to set up and manipulate, cannot leak, prevents the possibility of cavitation within the coupling device, and is much easier to sterilize and maintain during surgery. The design minimizes losses caused by shear wave conversion found in tapered solid acoustic velocity transformers operated at high frequencies. Computer simulations predicted good transfer of longitudinal waves. Impedance measurements, beam plots, Schlieren images, and force balance measurements verified strong focusing and suitable transfer of acoustic energy into water. At the focus, the -3 dB beam dimensions are 1.2 mm (axial) x 0.3 mm (transverse). Radiation force balance measurements indicate a power transfer efficiency of 40%. In vitro and in vivo tissue experiments confirmed the applicator's ability to produce hemostasis.

A low-cost fiber-optic instrument to colorimetrically detect patients with Barrett's esophagus for early detection of esophageal adenocarcinoma

In Barrett's esophagus, the precursor to esophageal adenocarcinoma, the squamocolumnar junction (SCJ) between the normal esophagus and the stomach like mucosa is proximally displaced. Currently it can be detected only by an expensive upper GI endoscopic procedure. We have developed a minimally invasive and easy to operate colorimetric instrument for the low-cost detection of Barrett's esophagus. The instrument is based on a flexible, narrow diameter, fiber-optic probe that performs a colorimetric scan of the esophageal lumen. The instrument was clinically evaluated in 50 subjects. The instrument could identify both symmetric and asymmetric SCJ's. The SCJ locations determined by the colorimetric instrument correlated strongly (R2 = 0.89) with those determined by endoscopy. The instrument identified the SCJ locations accurately (Mean of difference +/- SEM: 0.97 +/- 1.72 cm) and reproducibly (Mean of absolute difference +/- SEM: 1.33 +/- 1.40 cm). The instrument has a 90% sensitivity of identifying patients with Barrett's esophagus, based on the clinical algorithm that if the SCJ is located at a distance less than 37 cm from the teeth, then the subject has Barrett's esophagus, otherwise the subject does not have Barrett's esophagus. In conclusion, the colorimetric instrument has the potential of being a cost-effective way of determining patients likely to have Barrett's esophagus in the population.

Changes in esophageal wall layers during motility: measurements with a new miniature ultrasound suction device

We have developed a miniaturized ultrasound device that attaches to the gastrointestinal mucosa by suction and produces high-resolution (+/- 0.1 mm) images of the layers of the intestinal wall. The esophageal wall layers in a single sheep were measured during 20 occlusive contractions observed with simultaneous endoscopy, which revealed thickening of the inner circular muscle layer from 1.2 +/- 0.2 mm to 2.2 +/- 0.4 mm (p < 0.01), and during 20 dilations demonstrating thinning of the full thickness of the esophageal wall from 3.6 +/- 0.3 mm to 2.9 +/- 0.3 mm (p < 0.01). Safety experiments performed in two canine stomachs demonstrated no erosions or ulceration at any level of suction. Our investigations indicate that the M-mode suction ultrasound device can safely assess changes occurring in the layers of the esophageal wall during contractions and dilations and should be evaluated for the study of human intestinal motility.

A program of uterine activity monitoring and its effect on neonatal morbidity

In a recent study 34 patients at high risk for preterm delivery who received uterine activity monitoring were compared with 33 similar patients who attempted to detect contractions by palpation. The incidence of preterm delivery was significantly reduced among those using the uterine activity detection device, although all patients in both groups had the same prenatal care and educational intervention. When short-term neonatal morbidity associated with preterm delivery was compared between the two groups, adverse effects decreased significantly among those in the monitored group (p = 0.001). The majority of short-term morbidity in both groups was noted in those delivering preterm and thus was gestational age related. No significant difference was found in neonatal morbidity between the groups when the infants were delivered at less than 37 weeks' gestation. Uterine activity monitoring, which is effective in preventing preterm birth, is also efficacious in decreasing short-term neonatal morbidity.

The Disability Index of the Health Assessment Questionnaire is a predictor and correlate of outcome in the high-dose versus low-dose penicillamine in systemic sclerosis trial

OBJECTIVE

To explore the clinical implications of a score of > or =1.0 on the Disability Index of the Health Assessment Questionnaire (HAQ DI) at the first patient visit, and to examine the implications of improvement in HAQ DI score over 2 years in a cohort of systemic sclerosis (SSc) patients with diffuse cutaneous scleroderma.

METHODS

SSc skin and visceral involvement was assessed in 134 SSc patients with diffuse scleroderma (mean +/- SD disease duration of 10 +/- 4 months) when they entered a multicenter drug trial and again 2 years later. Mortality and the occurrence of scleroderma renal crisis were assessed for a mean +/- SD of 4.0 +/- 1.1 years. Logistic and linear regression analyses were used to examine the relationship of the baseline HAQ DI score to morbidity, mortality, and visceral involvement, as well as the relationship of changes in the HAQ DI score to changes in physical examination, laboratory, and functional variables over 2 years.

RESULTS

A baseline HAQ DI score of > or =1.0 was predictive of mortality (odds ratio 3.22, 95% confidence interval 1.097-9.468) over 4 years. Multivariate linear regression demonstrated that a model which included the erythrocyte sedimentation rate at baseline (P = 0.005) and changes at 2 years in the swollen joint count (P = 0.002), total skin score (P = 0.005), and white blood cell count (P = 0.005) best explained the change in HAQ DI score over 2 years (R2 = 0.528). The HAQ DI score and total skin score at baseline were highly correlated (correlation coefficient 0.368), as were changes in the HAQ DI score and the total skin score over 2 years (correlation coefficient 0.492). Although the HAQ DI score was heavily influenced by hand dysfunction at baseline and at 2 years, improvement (reduction) in the HAQ DI score over 2 years was related to factors other than hand dysfunction.

CONCLUSION

A baseline HAQ DI score of > or =1.0 predicted mortality over 4 years. Improvement in the HAQ DI score in these patients with diffuse scleroderma was associated with improvement in skin thickening, hand function, oral aperture, lung function, signs of arthritis, serum creatinine level, and the investigator's global assessment of improvement. The HAQ DI is a self-administered questionnaire that SSc patients can complete easily and rapidly and that gives the practicing physician important information about prognosis, patient status, and changes in disease course over time.

Real-time visualization of high-intensity focused ultrasound treatment using ultrasound imaging

High-intensity focused ultrasound (HIFU) and conventional B-mode ultrasound (US) imaging were synchronized to develop a system for real-time visualization of HIFU treatment. The system was tested in vivo in pig liver. The HIFU application resulted in the appearance of a hyperechoic spot at the focus that faded gradually after cessation of HIFU exposure. The duration of HIFU exposure needed for a hyperechoic spot to appear, was inversely related to the HIFU intensity. The threshold intensity required to produce a hyperechoic spot in liver in < 1 s was 970 W/cm(2), in situ. At this HIFU dose, no immediate cellular damage was observed, providing a potential for pretreatment targeting. The real-time visualization method was used in hemostasis of actively bleeding internal pelvic vessels, allowing targeting and monitoring of successful treatment. Real-time US imaging may provide a useful tool for image-guided HIFU therapy.