A new J.E probe for measurement of spatial profiles of power absorption in RF produced plasma

This paper reports an indigenously developed probe for the measurement of spatial profiles of the absorbed/generated RF power density Pabs (W/m3) in RF discharges. The technique utilizes a calibrated current (J) probe based on the Rogowski coil principle and an electric field (E) probe based on capacitive coupling, both integrated into a single probe called the J.E probe. Various aspects of the probe, such as its design, fabrication, calibration, and limitations, were resolved before it was used for obtaining axial profiles of RF power absorption/generation. Also presented are the first experimental results for the absorbed power density profiles at the fundamental (13.56 MHz) and harmonic (27.12 MHz) along the length of a capacitively coupled discharge. The axial scans between the powered and grounded electrode were taken at different argon gas pressures (10-800 mTorr) at a fixed RF power of 10 W. Detailed analysis of the results shows that even for systems with large electrode gaps, i.e., plasmas with long bulk plasma regions, practically all the fundamental power is absorbed in a narrow edge region near the powered electrode, irrespective of the pressure. Absorption is high near the RF electrode since the RF fields peak in this region. Another important conclusion is that stochastic absorption of the fundamental and harmonic generation proceeds fairly efficiently in the vicinity of the powered electrode even at high pressures. It may be mentioned that the probe technique introduced here is the first of its kind, and although there is considerable scope for miniaturization, it has, nonetheless, provided some key insights into the nature of RF power absorption in capacitive discharges.

A joint calibration technique for improving measurement accuracy of voltage and current probes during synchronous operation for RF-based plasma devices

This paper presents a joint calibration scheme for voltage (V) and current (I) probes that helps accurately resolve the voltage-current phase differences even when the difference is very close to 90°. The latter has been a major issue with V-I probes when used with miniature RF plasma devices such as the atmospheric pressure plasma jet (APPJ). Since the impedance of such miniature devices is predominantly capacitive, the phase difference between the voltage and current signals is very nearly 90°. It turns out, however, that when V-I probes are used with such devices without joint calibration, these frequently yield phase shifts over 90°. Also, since the power absorption is proportional to the resistive part of the impedance, it becomes very sensitive to the phase difference when it is close to ≈90°. Thus, it is important to be able to accurately resolve the phases. Post-calibration, V-I probes would be indispensable for the electrical characterization of APPJs for determining the average RF power P_av, plasma impedance Z_p, etc. Typical post-calibration V-I data yield Z_p ≈ 93.6 - j 1139 Ω (81.5 - j 1173 Ω) at P_av ≈9.8W (≈7.7W) for helium (argon) gas.

Matching-adjusted indirect treatment comparison of the efficacy of enzalutamide versus apalutamide for the treatment of nonmetastatic castration-resistant prostate cancer

Background

To date, the efficacy of the androgen receptor inhibitors enzalutamide and apalutamide for the treatment of nonmetastatic castration-resistant prostate cancer (nmCRPC) has not been compared directly in a clinical trial setting. Indirect comparisons can be used to assess relative efficacy and provide important information to guide treatment decisions. PROSPER and SPARTAN were double-blind, randomized, placebo-controlled, phase III trials in patients with nmCRPC with overall similar study designs and inclusion and exclusion criteria. Using an anchored matching-adjusted indirect comparison, based on the final data from the PROSPER and SPARTAN studies, we assessed the comparative efficacy of enzalutamide and apalutamide, both plus androgen deprivation therapy.

Methods

Using placebo as the common comparator, individual patient data from PROSPER were matched to the aggregate patient data from SPARTAN and efficacy endpoints from PROSPER were re-weighted accordingly. Patient baseline characteristics and endpoints were clinically and statistically tested to identify potential effect modifiers, according to National Institute for Health and Care Excellence guidelines. Hazard ratios for overall survival (OS), metastasis-free survival (MFS), and time to chemotherapy (TTCx) were re-estimated for PROSPER using weighted Cox proportional hazards models and indirectly compared with those of SPARTAN using a Bayesian network meta-analysis.

Results

Estimated hazard ratios [95% credible interval (CrI)] for enzalutamide versus apalutamide were 0.80 (95% CrI 0.58-1.10) for OS, 0.94 (95% CrI 0.69-1.29) for MFS2, and 0.90 (95% CrI 0.63-1.29) for TTCx. Similar results were seen for sensitivity analyses conducted for OS and MFS. Bayesian probability analyses showed a 91.7% favoring enzalutamide for OS, 65.1% for MFS, and 71.4% for TTCx.

Conclusions

The results of this matching-adjusted indirect comparison of final data from PROSPER and SPARTAN indicate comparable efficacy of enzalutamide and apalutamide with potentially a greater probability of longer MFS, OS, and TTCx in patients with nmCRPC treated with enzalutamide versus apalutamide.

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Enzalutamide and apalutamide relative efficacy assessed via an MAIC corrected for differences between PROSPER and SPARTAN.

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Enzalutamide and apalutamide showed similar efficacy with regards to MFS, OS, and TTCx.

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The Bayesian probability analyses were numerically in favor of enzalutamide being more effective than apalutamide.

Development and validation of the Physician's Global Assessment of Fingernail Psoriasis

BACKGROUND

Several clinician-rated scoring systems are available to assess nail psoriasis severity, but only one has been partially validated.

OBJECTIVE

To develop and validate the Physician's Global Assessment of Fingernail Psoriasis (PGA-F), a new clinician-rated severity scale.

METHODS

A literature review, concept elicitation, pilot cognitive debriefing and clinical expert consultations informed the development of the PGA-F. A multistage mixed-methods analysis consisted of practising dermatologist cognitive interviews (n = 10) for instrument clarity, relevance and comprehensiveness. Inter-rater reliability (IRR) of ratings from dermatologists (n = 22) and clinical trial investigators (n = 8) was tested using many-facet Rasch analysis. Concurrent validity between the PGA-F and modified Nail Psoriasis Severity Index (mNAPSI) at screening and baseline was assessed along with the degree of discrimination. Intraclass correlation coefficient (ICC) for single raters at multiple assessments determined IRR.

RESULTS

The PGA-F synthesizes severity ratings across multiple disease features that classify individuals into 1 of 5 levels (clear to severe). Cognitive interviews confirmed content validity: all (n = 10, 100%) participants who agreed clinical criteria were consistent with nail psoriasis; no mismatched severity levels; and training photographs were realistic representations. All PGA-F items were locally independent and targeted patients along the severity continuum with complementary precision (item fit statistics: < the 1.5 acceptability threshold; exact agreements among the dermatologists [44%] and trial investigators [61.5%] exceeded 40% of acceptability threshold). Clinician reliability exceeded the threshold of acceptability for dermatologists and clinical trial investigators: 0.85 and 0.73, respectively. There was adequate correlation (>0.30) between mNAPSI and PGA-F at baseline and Week 26 with significant discrimination of severity and monotonic increases in the mNAPSI for each level of categorical severity on the PGA-F. ICC results for each type of IRR indicate that clinicians were consistent in individual patient ratings.

CONCLUSION

The PGA-F is a rapid, valid and reliable clinician-rated severity scale for use in clinical practice and research.

Three-dimensional microscale hanging drop arrays with geometric control for drug screening and live tissue imaging

Existing three-dimensional (3D) culture techniques are limited by trade-offs between throughput, capacity for high-resolution imaging in living state, and geometric control. Here, we introduce a modular microscale hanging drop culture where simple design elements allow high replicates for drug screening, direct on-chip real-time or high-resolution confocal microscopy, and geometric control in 3D. Thousands of spheroids can be formed on our microchip in a single step and without any selective pressure from specific matrices. Microchip cultures from human LN229 glioblastoma and patient-derived mouse xenograft cells retained genomic alterations of originating tumors based on mate pair sequencing. We measured response to drugs over time with real-time microscopy on-chip. Last, by engineering droplets to form predetermined geometric shapes, we were able to manipulate the geometry of cultured cell masses. These outcomes can enable broad applications in advancing personalized medicine for cancer and drug discovery, tissue engineering, and stem cell research.

A novel ex situ diagnostic technique for characterizing harmonics in radio frequency discharges

An accurate, non-invasive ex situ diagnostic technique for analyzing plasma generated harmonics in radio frequency (RF) discharges is presented utilizing a broadband Dual Directional Coupler (DDC) that measures accurately both forward and reflected voltage signals in a transmission line. For usual applications such as monitoring forward and reflected power, the DDC is placed between the RF generator and the matching network (MN). However, the MN reflects all plasma generated harmonics back toward the plasma. Hence, no harmonics reach the generator side of the MN. Thus, for monitoring the harmonics, it is necessary to place the DDC between the impedance matching unit and the plasma, which was used for the first time in an asymmetric, parallel plate RF discharge at 13.56 MHz, 10 W-50 W at 200 mTorr (argon). The analysis of DDC data yields voltage, harmonic power contents, complex load impedance, plasma reflection coefficient, Voltage Standing Wave Ratio (VSWR), etc., for the fundamental frequency. For instance, at 10 W net input power, the computed plasma impedance is Z_L = R_p + jX_p, with R_p = 16.8 Ω and X_p = -81.9 Ω, yielding VSWR ≈11. Additionally, for 50 W input power, the third harmonic (72.31 mW) is dominant, followed by the second (8.28 mW) and fourth harmonics. In contrast, the literature states that the second harmonic is usually dominant, possibly due to the invasive nature of the diagnostics. Because harmonics are an important signature of processes taking place within the plasma, the proposed diagnostic can be effectively used for calibration and verification of theoretical models/simulations for resolving relevant physics issues.

Rapid Isothermal Amplification and Portable Detection System for SARS-CoV-2

The COVID-19 pandemic provides an urgent example where a gap exists between availability of state-of-the-art diagnostics and current needs. As assay details and primer sequences become widely known, many laboratories could perform diagnostic tests using methods such as RT-PCR or isothermal RT-LAMP amplification. A key advantage of RT-LAMP based approaches compared to RT-PCR is that RT-LAMP is known to be robust in detecting targets from unprocessed samples. In addition, RT-LAMP assays are performed at a constant temperature enabling speed, simplicity, and point-of-use testing. Here, we provide the details of an RT-LAMP isothermal assay for the detection of SARS-CoV-2 virus with performance comparable to currently approved tests using RT-PCR. We characterize the assay by introducing swabs in virus spiked synthetic nasal fluids, moving the swab to viral transport medium (VTM), and using a volume of that VTM for performing the amplification without an RNA extraction kit. The assay has a Limit-of-Detection (LOD) of 50 RNA copies/μL in the VTM solution within 20 minutes, and LOD of 5000 RNA copies/μL in the nasal solution. Additionally, we show the utility of this assay for real-time point-of-use testing by demonstrating detection of SARS-CoV-2 virus in less than 40 minutes using an additively manufactured cartridge and a smartphone-based reader. Finally, we explore the speed and cost advantages by comparing the required resources and workflows with RT-PCR. This work could accelerate the development and availability of SARS-CoV-2 diagnostics by proving alternatives to conventional laboratory benchtop tests.

Reliability of the hidradenitis suppurativa clinical response in the assessment of patients with hidradenitis suppurativa

BACKGROUND

Hidradenitis suppurativa clinical response (HiSCR) is a validated clinical end point for measuring response to treatment in patients with hidradenitis suppurativa (HS). Previous studies have reported on the validity, responsiveness and meaningfulness of the HiSCR.

OBJECTIVE

To evaluate the HiSCR for inter- and intrarater reliability characteristics.

METHODS

A stand-alone, two-site, prospective, non-interventional observational study consisted of 22 patients, with self-reported severity between mild, moderate and severe HS. The Patient Global Impression of Change (PGI-C) scale was completed by patients at Timepoint 2. Descriptive statistics of Hurley Stage, total abscesses, total draining fistulas, total inflammatory nodules and total AN count (sum of inflammatory nodules and lesions) were reported at two timepoints. Inter-rater reliability and intrarater reliability for the HS lesion count tool were evaluated at two timepoints (baseline and Day 7) using the HS lesion count tool. Intraclass correlation (ICC) coefficients of lesion counts were calculated to evaluate inter- and intrarater reliability of lesion counts between pairs of dermatologists.

RESULTS

The majority of patients demonstrated either no change or minimally worse PGI-C in HS scores. Descriptive statistics were similar between rater groups and timepoints assessed. Inter-rater ICC coefficients for abscess count at Timepoints 1 and 2 were 0.38 and 0.67. The ICC coefficients for draining fistula and AN count were ≥0.61 at both timepoints. In an exploratory model, ICC coefficients were ≥0.68 for all evaluated lesion counts. The test-retest reliability using ICC coefficients was ≥0.70 for total abscess, draining fistula, inflammatory nodule and AN count.

CONCLUSION

The HS lesion count tool had an acceptable inter- and intrarater reliability, indicating that HiSCR has a strong degree of reproducibility and consistency in the evaluation of patients with HS.

Susceptibility to corticosteroid-induced adrenal suppression: a genome-wide association study

BACKGROUND

A serious adverse effect of corticosteroid therapy is adrenal suppression. Our aim was to identify genetic variants affecting susceptibility to corticosteroid-induced adrenal suppression.

METHODS

We enrolled children with asthma who used inhaled corticosteroids as part of their treatment from 25 sites across the UK (discovery cohort), as part of the Pharmacogenetics of Adrenal Suppression with Inhaled Steroids (PASS) study. We included two validation cohorts, one comprising children with asthma (PASS study) and the other consisting of adults with chronic obstructive pulmonary disorder (COPD) who were recruited from two UK centres for the Pharmacogenomics of Adrenal Suppression in COPD (PASIC) study. Participants underwent a low-dose short synacthen test. Adrenal suppression was defined as peak cortisol less than 350 nmol/L (in children) and less than 500 nmol/L (in adults). A case-control genome-wide association study was done with the control subset augmented by Wellcome Trust Case Control Consortium 2 (WTCCC2) participants. Single nucleotide polymorphisms (SNPs) that fulfilled criteria to be advanced to replication were tested by a random-effects inverse variance meta-analysis. This report presents the primary analysis. The PASS study is registered in the European Genome-phenome Archive (EGA). The PASS study is complete whereas the PASIC study is ongoing.

FINDINGS

Between November, 2008, and September, 2011, 499 children were enrolled to the discovery cohort. Between October, 2011, and December, 2012, 81 children were enrolled to the paediatric validation cohort, and from February, 2010, to June, 2015, 78 adults were enrolled to the adult validation cohort. Adrenal suppression was present in 35 (7%) children in the discovery cohort and six (7%) children and 17 (22%) adults in the validation cohorts. In the discovery cohort, 40 SNPs were found to be associated with adrenal suppression (genome-wide significance p<1 × 10-6), including an intronic SNP within the PDGFD gene locus (rs591118; odds ratio [OR] 7·32, 95% CI 3·15-16·99; p=5·8 × 10-8). This finding for rs591118 was validated successfully in both the paediatric asthma (OR 3·86, 95% CI 1·19-12·50; p=0·02) and adult COPD (2·41, 1·10-5·28; p=0·03) cohorts. The proportions of patients with adrenal suppression by rs591118 genotype were six (3%) of 214 patients with the GG genotype, 15 (6%) of 244 with the AG genotype, and 22 (25%) of 87 with the AA genotype. Meta-analysis of the paediatric cohorts (discovery and validation) and all three cohorts showed genome-wide significance of rs591118 (respectively, OR 5·89, 95% CI 2·97-11·68; p=4·3 × 10-9; and 4·05, 2·00-8·21; p=3·5 × 10-10).

INTERPRETATION

Our findings suggest that genetic variation in the PDGFD gene locus increases the risk of adrenal suppression in children and adults who use corticosteroids to treat asthma and COPD, respectively.

FUNDING

Department of Health Chair in Pharmacogenetics.

Hands-free smartphone-based diagnostics for simultaneous detection of Zika, Chikungunya, and Dengue at point-of-care

Infectious diseases remain the world's top contributors to death and disability, and, with recent outbreaks of Zika virus infections there has been an urgency for simple, sensitive and easily translatable point-of-care tests. Here we demonstrate a novel point-of-care platform to diagnose infectious diseases from whole blood samples. A microfluidic platform performs minimal sample processing in a user-friendly diagnostics card followed by real-time reverse-transcription loop-mediated isothermal amplification (RT-LAMP) on the same card with pre-dried primers specific to viral targets. Our point-of-care platform uses a commercial smartphone to acquire real-time images of the amplification reaction and displays a visual read-out of the assay. We apply this system to detect closely related Zika, Dengue (types 1 and 3) and Chikungunya virus infections from whole blood on the same pre-printed chip with high specificity and clinically relevant sensitivity. Limit of detection of 1.56e5 PFU/mL of Zika virus from whole blood was achieved through our platform. With the ability to quantitate the target nucleic acid, this platform can also perform point-of-care patient surveillance for pathogen load or select biomarkers in whole blood.

Single use and conventional bronchoscopes for Broncho alveolar lavage (BAL) in research: a comparative study (NCT 02515591)

Background

Broncho alveolar lavage (BAL) is widely used for investigative research to study innate, cellular and humoral immune responses, and in early phase drug trials. Conventional (multiple use) flexible bronchoscopes have time and monetary costs associated with cleaning, and carries a small risk of cross infection. Single use bronchoscopes may provide an alternative, but have not been evaluated in this context.

Methods

Healthy volunteers underwent bronchoscopy at a day-case clinical research unit using the Ambu® aScope^TM single-use flexible intubation bronchoscope. Broncho alveolar lavage was performed from a sub segmental bronchus within the right middle lobe; a total of 200 ml of warmed normal saline was instilled then aspirated using handheld suction. BAL volume yield, cell yield and viability were recorded.

Results

Ten volunteers, (mean age 23 years, six male) participated. Bronchoscopies were carried out by one of two senior bronchoscopists, experienced in the technique of obtaining BAL for research purposes. The results were compared to 50 (mean age 23, 14 male) procedures performed using the conventional scope by the same two bronchoscopists. The total volume yield was significantly higher in the disposable group median 152 ml (IQR 141–166 ml) as compared to conventional 124 ml (110–135 ml), p = <0.01. The total cell yield and viability were similar in both groups, with no significant differences.

Conclusions

With single use bronchoscopes, we achieved a larger BAL volume yield than conventional bronchoscopes, with comparable cell yield and viability. Better volume yields can potentially reduce post procedure side effects such as pleuritic chest pain and cough. The risk of cross infection can be eliminated, providing reassurance to researchers and participants. Reduced maintenance requirements can be cost effective. These could potentially be used for early phase drug development studies.

Trial registration

This trial was registered prospectively in July 2015 with the National Clinical Trials register, with the following registration number assigned: NCT 02515591.

Hyponatremia - A rare complication of Gitelman's syndrome

Gitelman's syndrome (GS) is a rare autosomal recessive disorder caused by mutations in thiazide-sensitive NaCl cotransporter. We report a 49-year-old, normotensive lady with prolonged hypokalemia since her 20s who was diagnosed with GS at our renal clinic. During follow-up, she was found to have mild, asymptomatic, euvolemic hyponatremia with low serum uric acid, inappropriately high urine osmolality and sodium consistent with syndrome of inappropriate antidiuretic hormone-like presentation. Despite life-long urinary sodium losses, hyponatremia has rarely been reported in GS to be due to the primary disease process. We present relevant clinical data and hypothesize on why this disease per se may be a risk factor for dilutional hyponatremia.

Variation in warfarin prescribing and dosing in the UK: a national survey of anticoagulation clinics

WHAT IS KNOWN AND OBJECTIVE

Clinical practice in the initiation, prescribing, dosing and monitoring of warfarin in the UK varies, but this has not been adequately documented. The objective was to undertake a survey on current clinical practice in this area, and how it compares with national guidelines that have been developed by the British Committee for Standards in Haematology.

METHODS

A national online survey of anticoagulation clinics was performed using Survey Monkey(®) . The survey was designed to capture data for prescribing, dosing and monitoring of anticoagulation with warfarin.

RESULTS

Of 85 clinics who responded to the survey, most were run by secondary care (68%), facilitated by specialist nurses (58%) and followed standard guidelines for the management of warfarin (87%). The majority of clinics indicated their target international normalized ratio (INR) for patients with atrial fibrillation (AF) (69/73; 94·5%) was between 2·0 and 3·0, but the indicated target INR for mechanical heart valves was more variable. Initiation and loading dosing regimens were a major source of variability with uncertainty surrounding individual patient factors such as age, ethnicity and BMI.

WHAT IS NEW AND CONCLUSIONS

Current practice amongst UK anticoagulation clinics largely follows current national guidelines but better guidance on dosing, taking into account factors that determine interindividual variability in daily warfarin dose requirements would improve and standardize oral anticoagulation with warfarin.

Effect of a quadrivalent meningococcal ACWY glycoconjugate or a serogroup B meningococcal vaccine on meningococcal carriage: an observer-blind, phase 3 randomised clinical trial

BACKGROUND

Meningococcal conjugate vaccines protect individuals directly, but can also confer herd protection by interrupting carriage transmission. We assessed the effects of meningococcal quadrivalent glycoconjugate (MenACWY-CRM) or serogroup B (4CMenB) vaccination on meningococcal carriage rates in 18-24-year-olds.

METHODS

In this phase 3, observer-blind, randomised controlled trial, university students aged 18-24 years from ten sites in England were randomly assigned (1:1:1, block size of three) to receive two doses 1 month apart of Japanese Encephalitis vaccine (controls), 4CMenB, or one dose of MenACWY-CRM then placebo. Participants were randomised with a validated computer-generated random allocation list. Participants and outcome-assessors were masked to the treatment group. Meningococci were isolated from oropharyngeal swabs collected before vaccination and at five scheduled intervals over 1 year. Primary outcomes were cross-sectional carriage 1 month after each vaccine course. Secondary outcomes included comparisons of carriage at any timepoint after primary analysis until study termination. Reactogenicity and adverse events were monitored throughout the study. Analysis was done on the modified intention-to-treat population, which included all enrolled participants who received a study vaccination and provided at least one assessable swab after baseline. This trial is registered with ClinicalTrials.gov, registration number NCT01214850.

FINDINGS

Between Sept 21 and Dec 21, 2010, 2954 participants were randomly assigned (987 assigned to control [984 analysed], 979 assigned to 4CMenB [974 analysed], 988 assigned to MenACWY-CRM [983 analysed]); 33% of the 4CMenB group, 34% of the MenACWY-CRM group, and 31% of the control group were positive for meningococcal carriage at study entry. By 1 month, there was no significant difference in carriage between controls and 4CMenB (odds ratio 1·2, 95% CI 0·8-1·7) or MenACWY-CRM (0·9, [0·6-1·3]) groups. From 3 months after dose two, 4CMenB vaccination resulted in significantly lower carriage of any meningococcal strain (18·2% [95% CI 3·4-30·8] carriage reduction), capsular groups BCWY (26·6% [10·5-39·9] carriage reduction), capsular groups CWY (29·6% [8·1-46·0] carriage reduction), and serogroups CWY (28·5% [2·8-47·5] carriage reduction) compared with control vaccination. Significantly lower carriage rates were also noted in the MenACWY-CRM group compared with controls: 39·0% (95% CI 17·3-55·0) carriage reduction for serogroup Y and 36·2% (15·6-51·7) carriage reduction for serogroup CWY. Study vaccines were generally well tolerated, with increased rates of transient local injection pain and myalgia in the 4CMenB group. No safety concerns were identified.

INTERPRETATION

Although we detected no significant difference between groups at 1 month after vaccine course, MenACWY-CRM and 4CMenB vaccines reduced meningococcal carriage rates during 12 months after vaccination and therefore might affect transmission when widely implemented.

FUNDING

Novartis Vaccines.

Assessment of endogenous, oral and inhaled steroid cross-reactivity in the Roche cortisol immunoassay

BACKGROUND

Inhaled steroids are widely used for the treatment of asthma. Concerns over adrenal suppression when used at high doses or in combination with drugs such as ritonavir exist, requiring the measurement of serum cortisol. Herein, we investigate the cross-reactivity of the inhaled steroids betamethasone, fluticasone and beclomethasone in the Roche cortisol immunoassay, in addition to five other steroids.

METHODS

Five replicates were produced from a serum pool for each of the eight steroids at a final concentration of 0.1 and 1 µg/mL. Each steroid was dissolved in 50% methanol, with 50% methanol of the same volume added to the control sample. The cross-reactivity of each steroid in the cortisol assay was calculated.

RESULTS

There was no statistically or clinically significant cross-reactivity in the measurement of cortisol when fluticasone, beclomethasone or betamethasone were spiked at 0.1 and 1.0 µg/mL, except for beclomethasone at a concentration of 1 µg/mL (1490 nmol/L) with a cross-reactivity of 1.6%, which is unlikely to be clinically significant. At both steroid concentrations investigated, prednisolone, 17-hydroxyprogesterone and 11-deoxycortisol exhibited statistically significant cross-reactivities that were greater than the least significant change of the assay (13.1%), whereas dexamethasone and metyrapone did not. Mean inter-assay precision was 1.5% (405-1586 nmol/L).

CONCLUSION

The cross-reactivity of the inhaled steroids; betamethasone, fluticasone and beclomethasone in the Roche cortisol immunoassay are unlikely to be clinically significant at the concentrations found in patients on therapeutic doses. This will enable confident assessment of adrenal status in patients at risk of adrenal suppression.

P1-08-21: Demographic and Clinical Characteristics of Metastatic Breast Cancer Patients and Biomarker-Based Prevalence in the UK, Germany, France, Spain and Italy (EU-5)

Background: Much peer-reviewed literature focuses on metastatic breast cancer (mBC) treatment regimens. However, research around mBC patients’ demographic/clinical characteristics across Europe is limited. This study compared such mBC characteristics as well as biomarker-based prevalence across the EU-5.

Methods: IMS LifeLink™ Oncology Analyzer (OA) database, based upon practicing oncologist surveys, was used to identify mBC patients aged ≥18 between 01/2005-06/2010. The study investigated the distribution of mBC population based on age, biomarker, co-morbidities and stage at diagnosis. This study also estimated the proportion of patients, and sites of metastasis, by lines of drug therapies (LOT).

Results: A total of 186,640 mBC patients were identified — Germany (30.2%), France (22.4%), UK (21.2%), Italy (17.7%) and Spain (8.4%). The majority of patients were aged 61–70yrs (24%-32%), except in Spain (22.3% aged 71–80yrs). Proportion of mBC patients with ≥1 co-morbid condition were highest in Germany (36.3%), followed by Spain (32.8%), UK (31.5%), Italy (27.6%) and France (20.1%), with diabetes (12.9−23.9%) and cardiac dysfunction (5.2−21.7%) being most prevalent. The distribution of mBC patients by biomarker status was 53.9% HER-/HR+, 17.8% HER+/HR+, 11.1% HER+/HR- and 17.2% triple negative, and was similar amongst the EU5 countries. The top three metastatic sites were bone (54.4%), lung (36.0%) and liver (32.7%), with proportion of bone metastasis increasing from 1st LOT (38.1%) to 4th LOT (69.6%). Almost 50% of the mBC patients were diagnosed at Stage IV, 14% at Stage III, 26% at Stage II and 6% at Stage I. Of all mBC patients, 93% received 1st LOT, 31% received 2nd LOT, 27% received 3rd LOT and 6.8% received 4thLOT.

Conclusion: In the EU-5, mBC patients were primarily elderly and HER-/HR+. The burden of bone metastasis was higher in later LOTs. Following the 1st LOT, fewer patients moved to subsequent treatments. Additional research on EU-5 clinical practice patterns is warranted.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-08-21.

Optimal ultrasonic array focusing in attenuative media

This paper presents a parametric study on the efficiency of ultrasound focusing in an attenuative medium, using phased arrays. Specifically, an analytical model of ultrasound wave focusing in a homogeneous, isotropic and attenuative fluid with point sources is presented. Calculations based on the model have shown that in an attenuative medium, an optimum frequency exists for the best focusing performance for a particular size of aperture and focal distance. The effect of different f numbers on the focusing performance in the attenuative medium is further investigated. The information obtained from the analytical model provides insights into the design and installation of a phased transducer array for energy efficient wave focusing.

Spontaneous hemothorax following anticoagulation with low-molecular-weight heparin

OBJECTIVE

To report a case of spontaneous hemothorax following anticoagulation with low-molecular-weight heparin (LMWH) for the management of suspected pulmonary embolism.

CASE SUMMARY

A 66-year-old man with a background history of breast carcinoma was admitted with pleuritic chest pain. He was initially managed as a suspected case of pulmonary embolism. Dalteparin, an LMWH, was started at a maximum dose of 18,000 units subcutaneously once daily, according to British national prescribing guidelines. On day 4, following 3 doses of dalteparin, the patient developed acute respiratory distress attributable to a massive right hemothorax confirmed by computed tomography pulmonary angiography (CTPA) and intercostal drainage of 1500 mL of frank blood. CTPA identified no pulmonary embolus or vascular abnormalities. Reaccumulation of hemothorax occurred over the 48 hours following drain removal, necessitating insertion of a second drain, which removed 1400 mL of blood-stained fluid. The patient's hemoglobin decreased from 12.7 to 8.5 g/dL and he received a 3-unit blood transfusion. Histologic assessment of pleural fluid revealed no malignancy and results of video-assisted thoracoscopic surgery were normal. Discontinuation of dalteparin on day 4 led to resolution of symptoms.

DISCUSSION

The causal association between anticoagulant therapy and spontaneous hemothorax remains relatively uncommon. The striking temporal relationship between commencing dalteparin on day 1 and subsequent development of effusion on day 4, following 3 doses of LMWH, led us to believe that the bleed occurred as a result of the therapy. Exclusion of other causes strengthened this conclusion. Application of the Naranjo probability scale categorized this adverse reaction as being probably due to LMWH.

CONCLUSIONS

Spontaneous hemothorax is a rare phenomenon in conjunction with LMWH but should be considered in cases of acute respiratory distress following commencement of LMWH.

Decolorization of anaerobically digested molasses spent wash by Pseudomonas putida

The distillery wastewater (spent wash) contains dark-brown colored recalcitrant organic compounds that are not amenable to conventional biological treatment. The characteristic recalcitrance to decolorization is due to the presence of brown melanoidin polymers. In the present study, feasibility of using Pseudomonas putida strain U for decolorization of spent wash was demonstrated. Batch cultures of P. putida decolourized spent wash by 24%, 2- fold higher decolorization was achieved following immobilization in calcium alginate beads. Glucose concentration was critical for decolourization and improved color removal efficiency was obtained by periodic replenishment of glucose. Decolourization was also observed with lactose or whey as alternative carbon sources. The results of our study suggest that P. putida could be used for biological decolorization of molasses spent washes and that supplementation with whey (a by-product from cheese industry) can offer economical viability to the process.

Bacterial adhesion to bisphosphonate coated hydroxyapatite

Staphylococcus aureus (S. aureus) is commonly associated with microbial infection of orthopaedic implants. Such infections often lead to osteomyelitis, which may result in failure of the implant due to localised bone destruction. Bacterial adhesion and subsequent colonisation of the device may occur as a consequence of contamination during surgery, or by seeding from a distant site through the blood circulation. Coating of the hydroxyapatite (HA) ceramic component of artificial hip joints with the bisphosphonates clodronate (C) and pamidronate (P) has been proposed as a means to minimise osteolysis and thereby prevent loosening of the implant. However, the effect of the bisphosphonate coating on bacterial adhesion to the HA materials must be determined before this approach can be implemented. In this study coated HA materials were incubated with the S. aureus and the number of adherent bacteria determined using the Modified Vortex Device (MVD) method. The number of bacteria adherent to the P coated HA material was significantly greater than that adherent to uncoated HA (60-fold increase) or to the C coated HA (90-fold increase). Therefore, even though earlier studies suggested that P bound to HA may improve osseointegration, the results presented would suggest that the use of this coating may be limited by the potential increased susceptibility of the coated device to infection.