Plasma-activated liquid as a potential decontaminant in healthcare: assessment of antibacterial activity and use with cleaning cloths

BACKGROUND

Cold air plasma (CAP) can generate plasma-activated liquids (PALs) with high concentrations of reactive oxygen (ROS) and nitrogen species (RNS), e.g., nitrites, with antimicrobial properties.

AIM

We investigated the concentrations of ROS and RNS in saline PAL. We assessed planktonic bacterial inactivation by PAL and the decontamination of contaminated cleaning cloths.

METHODS

Phosphate-buffered saline (PBS) was treated with an air-driven CAP jet for 90 or 300 s to generate PAL. The ROS and RNS were measured using quantitative fluorescent (2,7-dichlorofluorescin diacetate) and colourimetric (Greiss) assays. Isolates of MRSA and Escherichia coli were incubated in PAL overnight and inactivation measured through colony forming unit (cfu) assays. Sections of cleaning cloths were incubated with MRSA and E. coli, and treated with PAL for 1 h. Bacterial inactivation was measured through resazurin reduction assays.

RESULTS

Nitrites increased from 0.1 μM in untreated PBS to 49.1 μM and to 94.0 μM in 90- and 300-s CAP-treated PAL, respectively. ROS increased from 30 μM in untreated PBS to 75 μM and to 103 μM in 90- and 300-s CAP-treated PAL, respectively. 90-s PAL reduced MRSA and E. coli viability (P<0.05) and 300-s PAL resulted in more than a 7-log reduction of both. One-hour treatment of contaminated cleaning cloths in PAL resulted in a 55% and 73% reduction in viable MRSA and E. coli, respectively (P<0.05).

CONCLUSION

Inactivation of planktonic bacteria correlated with ROS and RNS concentrations. PAL reduced bacteria contaminated cleaning cloths. PAL has potential as a hospital disinfectant, including cleaning cloths.

Results from a phase I trial of pembrolizumab plus vorinostat in relapsed/refractory B-cell non-Hodgkin lymphoma

Outcomes after programmed death-1 (PD-1) blockade in B-cell lymphomas are disappointing with few durable responses. Histone deacetylase inhibitors exhibit favorable immunomodulatory effects and demonstrate synergistic anti-tumor immune responses with anti-PD-1 therapy in preclinical models. We, therefore, developed a phase I study to evaluate the safety and preliminary efficacy of pembrolizumab with vorinostat in relapsed/refractory B-cell lymphomas. Patients were treated in a dose-escalation cohort using a Rolling 6 design followed by an expansion cohort at the recommended phase II dose (R2PD). Fifty-two patients were enrolled (32 Hodgkin and 20 non-Hodgkin lymphoma [NHL]). Here, we report safety data from the dose escalation cohort, and the toxicity and efficacy within NHL patients. Vorinostat was administered twice daily on days 1-5 and 8-12 (dose-level [DL]1: 100 mg; DL2: 200 mg) and pembrolizumab (200 mg) was administered on day 1 of each 3-week cycle. Of six patients treated at DL1, one had a dose-limiting toxicity (DLT) (Stevens-Johnson syndrome [SJS]), and one of six had a DLT at DL2 (thromboembolism); therefore, DL2 was the RP2D. The patient developing SJS was treated with corticosteroids, infliximab, and cyclosporine but ultimately died of invasive fungal infection from the extensive immunosuppression used to treat the SJS. The most common adverse events were hypertension, diarrhea, and cytopenias. Of 20 NHL patients, nine had follicular lymphoma (FL) and 11 had diffuse large B-cell lymphoma (DLBCL). Five DLBCL patients had primary mediastinal B-cell lymphoma (PMBL). The complete and overall response rates (CR and ORR) were 11% and 22% for FL and 45% and 55% for all DLBCL. Amongst DLBCL, the CR and ORR was 80% and 80% for PMBL and 17% and 33% for non-PMBL. In conclusion, pembrolizumab with vorinostat was tolerable and produced responses in relapsed/refractory B-cell NHL, with particularly notable efficacy in PMBL (clinicaltrials gov. Identifier: NCT03150329).

Pembrolizumab plus vorinostat induces responses in patients with Hodgkin lymphoma refractory to prior PD-1 blockade

This phase 1 study evaluated the addition of vorinostat to pembrolizumab in patients with relapsed/refractory (RR) classical Hodgkin lymphoma (cHL), diffuse large B-cell lymphoma, and follicular lymphoma. We report the results in cases of cHL. Adult patients with RR cHL who had received ≥1 prior lines of therapy and were ineligible for transplantation were treated in a dose-escalation cohort with 2 dose levels (DLs) and then on an expansion cohort at the recommended phase 2 dose (RP2D) in 21-day cycles. Vorinostat 100 mg twice a day (DL1) and 200 mg twice a day (DL2) was administered orally from days 1 to 5 and 8 to 12; all patients received pembrolizumab 200 mg IV every 3 weeks. The primary end point was safety and determination of RP2D. In total, 32 patients with cHL were enrolled, including 30 at DL2 (RP2D); 78% had received prior anti-programmed cell death 1 (anti-PD-1) therapy, and 56% were PD-1 refractory. Grade ≥3 adverse events (AEs) included hypertension (9%), neutropenia (9%), hypophosphatemia (9%), thrombocytopenia (6%), and lymphopenia (6%). Immune-related AEs included grade 1 or 2 thyroiditis (13%), grade 1 rash (6%), and grade 3 esophagitis/duodenitis (3%). The overall response rate (ORR) was 72% and complete response (CR) rate was 34%. Patients refractory to prior PD-1 blockade (n = 18) had ORR and CR rates of 56% and 11%, respectively. Pembrolizumab and vorinostat was well tolerated with a high ORR rate in RR cHL including in anti-PD-1-refractory disease. This trial was registered at www.clinicaltrials.gov as #NCT03150329.

1362 ANTICHOLINERGIC PRESCRIBING HABITS AND ITS ASSOCIATIONS IN A COMMUNITY POPULATION OF PEOPLE LIVING WITH DEMENTIA

Introduction

Many commonly prescribed medications have inadvertent anticholinergic effects. People with Dementia (PwD) are more vulnerable to these effects and at risk of adverse outcomes, the risk being higher with a greater degree of anticholinergic exposure. We investigated prescribing patterns and Anticholinergic burden (ACB) in a cohort of community-dwelling older adults with dementia and aimed to explore the effect of ACB on cognition, mood, and quality of life(QoL).

Method

The medication and demographic information for 87 (39 female) community-dwelling PwD were obtained from Electronic Care Summaries. We used the German Anticholinergic Burden Scale (GABS) to measure ACB. Additionally, we investigated associations between ACB and cognitive (ADAS-Cog), functional (BADL) and QoL (DemQoL) assessments.

Results

28.7% of participants had a clinically significant score (ACB&gt; 2). The most commonly prescribed medications with ACB were Lansoprazole(18.3%), Mirtazapine(12.6%) and Codeine(12.6%). ACB was higher in males and negatively correlated with age, r(87)=-.21,p=.03. There was no association between ACB and cognition, QoL, functional independence, and neuropsychiatric symptoms. Over six months, PLWD with no ACB had a greater negative change in neuropsychiatric symptoms[t(18)=2.27,p=.04] and functional independence[t(23)=-3.8,p=.001], indicating greater dependence and worsening neuropsychiatric symptoms.

Conclusion

A third of PLWD in the community had clinically significant ACB. No ACB was associated with worsening neuropsychiatric symptoms and functional dependence over a six-month period. Community prescribers should consider regular medication reviews with PLWD and carers to ensure medications are prescribed safely and appropriately.

Skin and respiratory ill-health attributed to occupational face mask use

BACKGROUND

Face mask use in the workplace has become widespread since the onset of the Covid-19 pandemic and has been anecdotally linked to adverse health consequences.

AIMS

To examine reports of adverse health consequences of occupational face mask use received by The Health and Occupation Research (THOR) network before and after the pandemic onset.

METHODS

THOR databases were searched to identify all cases of ill-health attributed to 'face mask' or similar suspected causative agent between 1 January 2010 and 30 June 2021.

RESULTS

Thirty two cases were identified in total, 18 reported by occupational physicians and 14 by dermatologists. Seventy-five per cent of cases were reported after the pandemic onset and 91% cases were in the health and social care sector. 25 of the 35 (71%) diagnoses were dermatological, the most frequent diagnoses being contact dermatitis (14 cases) and folliculitis/acne (6 cases). Of the seven respiratory diagnoses, four were exacerbation of pre-existing asthma.

CONCLUSIONS

There is evidence of an abrupt increase in reports of predominantly dermatological ill-health attributed to occupational face mask use since the start of the pandemic. Respiratory presentations have also occurred.

Defining core patient descriptors for perforated peptic ulcer research: international Delphi

BACKGROUND

Perforated peptic ulcer (PPU) remains a common condition globally with significant morbidity and mortality. Previous work has demonstrated variation in reporting of patient characteristics in PPU studies, making comparison of studies and outcomes difficult. The aim of this study was to standardize the reporting of patient characteristics, by creating a core descriptor set (CDS) of important descriptors that should be consistently reported in PPU research.

METHODS

Candidate descriptors were identified through systematic review and stakeholder proposals. An international Delphi exercise involving three survey rounds was undertaken to obtain consensus on key patient characteristics for future research. Participants rated items on a scale of 1-9 with respect to their importance. Items meeting a predetermined threshold (rated 7-9 by over 70 per cent of stakeholders) were included in the final set and ratified at a consensus meeting. Feedback was provided between rounds to allow refinement of ratings.

RESULTS

Some 116 clinicians were recruited from 29 countries. A total of 63 descriptors were longlisted from the literature, and 27 were proposed by stakeholders. After three survey rounds and a consensus meeting, 27 descriptors were included in the CDS. These covered demographic variables and co-morbidities, risk factors for PPU, presentation and pathway factors, need for organ support, biochemical parameters, prognostic tools, perforation details, and surgical history.

CONCLUSION

This study defines the core descriptive items for PPU research, which will allow more robust synthesis of studies.

1447Childhood risk factors and cardiovascular disease outcomes in adulthood. Preliminary findings from the International Childhood Cardiovascular Cohort (i3C) Consortium

Background

Atherosclerosis develops decades before clinical cardiovascular disease (cCVD) occurs. Longitudinally, childhood risk factors predict adult pre-clinical atherosclerosis. There is currently no evidence directly linking childhood risk factors to cCVD.

Purpose

To provide the first direct evidence of any association between known risk factors for CVD when measured in childhood and adult CVD incidence and death.

Methods

Using i3C Consortium data, we linked childhood risk factors to adult cCVD. cCVD events were ascertained by participant re-contact in the US and Australia, medically adjudicated hospital records; and using the Finnish national health registry. Of 16,964 adult participants (mean age 49 years) examined during ages 3–19, 201 people with any cCVD event (70% coronary artery, 25% cerebrovascular, and 5% peripheral artery disease) have been determined. The analysis included Cox proportional hazard models. Each model was adjusted for childhood age, age at followup, sex and cohort/race. Continuous childhood variables were z-scored for each participant's last repeated measure during childhood.

Results

Childhood body mass index (BMI), serum total cholesterol (TC) and triglycerides, and systolic blood pressure were positively associated with adult cCVD events (P<0.0001). Smoking in childhood was associated with nearly 50% increased risk of adult cCVD (P=0.08). BMI; TC remained significant in the simultaneous risk factor model. The adjudication pipeline suggests that over 500 hospitalized cCVD events will be found on completion. Regression using the full set of imputed events yielded similar findings. Analysis of deaths is in process.

Childhood risk factor link to adult CVD Childhood risk variable Single risk factors models Simultaneous risk factor model n cCVD events/N at risk Hazard ratio (95% Confidence limits) p n cCVD events/N at risk Hazard ratio (95% Confidence limits) p Body Mass Index 201/16964 1.52 (1.33–1.73) <0.0001 142/11124 1.37 (1.14–1.64) 0.0008 Total cholesterol 191/13778 1.32 (1.14–1.52) 0.0001 " 1.21 (1.02–1.43) 0.03 Triglycerides 191/13654 1.17 (1.04–1.33) 0.01 " 1.04 (0.88–1.24) 0.6 Systolic blood pressure 190/14883 1.28 (1.11–1.48) 0.0007 " 1.18 (0.99–1.42) 0.07 Regular smoking ≥1/day 151/13436 1.44 (0.96–2.16) 0.08 " 1.43 (0.94–2.17) 0.10 Hazard ratios = increased risk per one standard deviation increase in continuous risk variables. E.g. every ∼0.9 mmol/L or ∼33 mg/dL increase in childhood total cholesterol is associated with a ∼32% and 21% increase in adult CVD risk in single and simultaneous risk factor models respectively. “Simultaneous risk factor model” recognizes that the risk factors are causally connected.

Conclusion

Childhood CVD risk factors predicts adult cCVD with implications for primordial CVD prevention.

Acknowledgement/Funding

National Heart, Lung, and Blood Institute (NHLBI)

Sidney George Shaw, DPhil (1948-2017)

On March 4, 2017 at the age of 68, Sidney George Shaw (Sid) unexpectedly died from complications following surgery, only four years after retiring from the University of Bern. Trained in biochemistry at Oxford University, Sid had quickly moved into molecular pharmacology and became a key investigator in the field of enzyme biochemistry, vasoactive peptide research, and receptor signaling. Sid spent half his life in Switzerland, after moving to the University of Bern in 1984. This article, written by his friends and colleagues who knew him and worked with him during different stages of his career, summarizes his life, his passions, and his achievements in biomedical research. It also includes personal memories relating to a dear friend and outstanding scientist whose intellectual curiosity, humility, and honesty will remain an example to us all.

Intensify production, transform biomass to energy and novel goods and protect soils in Europe-A vision how to mobilize marginal lands

The rapid increase of the world population constantly demands more food production from agricultural soils. This causes conflicts, since at the same time strong interest arises on novel bio-based products from agriculture, and new perspectives for rural landscapes with their valuable ecosystem services. Agriculture is in transition to fulfill these demands. In many countries, conventional farming, influenced by post-war food requirements, has largely been transformed into integrated and sustainable farming. However, since it is estimated that agricultural production systems will have to produce food for a global population that might amount to 9.1 billion by 2050 and over 10 billion by the end of the century, we will require an even smarter use of the available land, including fallow and derelict sites. One of the biggest challenges is to reverse non-sustainable management and land degradation. Innovative technologies and principles have to be applied to characterize marginal lands, explore options for remediation and re-establish productivity. With view to the heterogeneity of agricultural lands, it is more than logical to apply specific crop management and production practices according to soil conditions. Cross-fertilizing with conservation agriculture, such a novel approach will provide (1) increased resource use efficiency by producing more with less (ensuring food security), (2) improved product quality, (3) ameliorated nutritional status in food and feed products, (4) increased sustainability, (5) product traceability and (6) minimized negative environmental impacts notably on biodiversity and ecological functions. A sustainable strategy for future agriculture should concentrate on production of food and fodder, before utilizing bulk fractions for emerging bio-based products and convert residual stage products to compost, biochar and bioenergy. The present position paper discusses recent developments to indicate how to unlock the potentials of marginal land.

Controlling wettability of PECVD-deposited dual organosilicon/carboxylic acid films to influence DNA hybridisation assay efficiency

Plasma oxidation of Zeonor and deposition of TEOS/AA thin film showing dual layer effect on the surface.

Ultrasensitive microarray bioassays using cyanine5 dye-doped silica nanoparticles

Herein we report the use of high brightness Cyanine5-doped silica nanoparticles (NPs) for the detection of antibodies or DNA in microarray bioassays. NP labels showed negligible non-specific binding, greater sensitivity and lower limits of detection when compared to free dye-labelled biomolecules. Moreover, the spotted microarrays used in this study required low NP and antibody concentrations to generate large data sets with improved statistical accuracy. These NPs have significant potential for use in biosensing for disease detection.

Cost implications and oncological outcomes for laparoscopic versus open surgery for right hemicolectomy

INTRODUCTION

Recent studies have suggested that laparoscopic surgery for colorectal resection confers a cost benefit compared with open surgery. These studies have considered a wide range of colorectal operations together rather than focusing on a single procedure. Our study compared direct clinical costs for laparoscopic versus open right hemicolectomy.

METHODS

Clinicopathological data and cost of treatment for all patients who underwent a right hemicolectomy between 2012 and 2013 were collected. The primary outcome was total cost of treatment. Secondary outcomes were length of stay, operative time and morbidity. The minimum follow-up duration was 12 months. Costs for laparoscopic and open surgery for elective resection alone were compared. Further analyses were performed comparing emergency cases with elective cases and cancer with non-cancer cases.

RESULTS

There were 83 patients who underwent a right hemicolectomy during the study period and of these, 65 had an elective procedure. The total cost of a laparoscopic procedure was £3,998.12 compared with £3,427.50 for open surgery (p=0.039). The length of stay was shorter for laparoscopic surgery while the cost of an emergency right hemicolectomy was significantly greater than for elective surgery.

CONCLUSIONS

Although the length of stay for laparoscopic surgery was shorter, this did not translate to a reduction in cost. The cost benefit from a shorter length of stay was offset by a greater cost of consumables. Cost effectiveness analyses should be designed carefully, and they should consider individual operations separately when making healthcare management and funding decisions.

Cicada Wing Surface Topography: An Investigation into the Bactericidal Properties of Nanostructural Features

Recently, the surface of the wings of the Psaltoda claripennis cicada species has been shown to possess bactericidal properties and it has been suggested that the nanostructure present on the wings was responsible for the bacterial death. We have studied the surface-based nanostructure and bactericidal activity of the wings of three different cicadas (Megapomponia intermedia, Ayuthia spectabile and Cryptotympana aguila) in order to correlate the relationship between the observed surface topographical features and their bactericidal properties. Atomic force microscopy and scanning electron microscopy performed in this study revealed that the tested wing species contained a highly uniform, nanopillar structure on the surface. The bactericidal properties of the cicada wings were investigated by assessing the viability of autofluorescent Pseudomonas fluorescens cells following static adhesion assays and targeted dead/live fluorescence staining through direct microscopic counting methods. These experiments revealed a 20-25% bacterial surface coverage on all tested wing species; however, significant bactericidal properties were observed in the M. intermedia and C. aguila species as revealed by the high dead:live cell ratio on their surfaces. The combined results suggest a strong correlation between the bactericidal properties of the wings and the scale of the nanotopography present on the different wing surfaces.

Multivalent linkers for improved covalent binding of oligonucleotides to dye-doped silica nanoparticles

This paper describes the fabrication of oligonucleotide-coated Cy5-doped silica nanoparticles using a combination of multivalent linkers and their use in surface-based DNA sandwich hybridization assays. Dipodal silane is introduced as a means to fabricate amine-coated silica nanoparticles and its advantages compared to monopodal silanes are discussed. The use of dipodal silane in conjunction with three different polymer linkers (oxidized dextran, linear and 8-arm polyethylene glycol (PEG)) to immobilize single-stranded DNA to Cy5-doped nanoparticles is investigated and dynamic light scattering measurements and Fourier transform infrared spectroscopy are used to follow the progression of the functionalization of the nanoparticles. We observe a significant improvement in the binding stability of the single-stranded DNA when the dipodal silane and 8-arm PEG are used in combination, when compared to alternative conjugation strategies. Both 8mer and 22mer oligonucleotides are securely conjugated to the high-brightness nanoparticles and their availability to hybridize with a complementary strand is confirmed using solution-based DNA hybridization experiments. In addition, a full surface-based sandwich assay demonstrates the potential these nanoparticles have in the detection of less than 500 femtomolar of a DNA analogue of micro RNA, miR-451.

Fabrication and characterisation of spin coated oxidised PMMA to provide a robust surface for on-chip assays

Smooth, thin PMMA layers have been oxidised using two methods on various surfaces. The longevity of activation and ability of the films to bind and retain biomolecules has been investigated.

Cold atmospheric pressure plasma and decontamination. Can it contribute to preventing hospital-acquired infections?

Healthcare-associated infections (HCAIs) affect ∼4.5 million patients in Europe alone annually. With the ever-increasing number of 'multi-resistant' micro-organisms, alternative and more effective methods of environmental decontamination are being sought as an important component of infection prevention and control. One of these is the use of cold atmospheric pressure plasma (CAPP) systems with clinical applications in healthcare facilities. CAPPs have been shown to demonstrate antimicrobial, antifungal and antiviral properties and have been adopted for other uses in clinical medicine over the past decade. CAPPs vary in their physical and chemical nature depending on the plasma-generating mechanism (e.g. plasma jet, dielectric barrier discharge, etc.). CAPP systems produce a 'cocktail' of species including positive and negative ions, reactive atoms and molecules (e.g. atomic oxygen, ozone, superoxide and oxides of nitrogen), intense electric fields, and ultraviolet radiation (UV). The effects of these ions have been studied on micro-organisms, skin, blood, and DNA; thus, a range of possible applications of CAPPs has been identified, including surface decontamination, wound healing, biofilm removal, and even cancer therapy. Here we evaluate plasma devices, their applications, mode of action and their potential role specifically in combating HCAIs on clinical surfaces.

A spatially resolved retarding field energy analyzer design suitable for uniformity analysis across the surface of a semiconductor wafer

A novel retarding field energy analyzer design capable of measuring the spatial uniformity of the ion energy and ion flux across the surface of a semiconductor wafer is presented. The design consists of 13 individual, compact-sized, analyzers, all of which are multiplexed and controlled by a single acquisition unit. The analyzers were tested to have less than 2% variability from unit to unit due to tight manufacturing tolerances. The main sensor assembly consists of a 300 mm disk to mimic a semiconductor wafer and the plasma sampling orifices of each sensor are flush with disk surface. This device is placed directly on top of the rf biased electrode, at the wafer location, in an industrial capacitively coupled plasma reactor without the need for any modification to the electrode structure. The ion energy distribution, average ion energy, and average ion flux were measured at the 13 locations over the surface of the powered electrode to determine the degree of spatial nonuniformity. The ion energy and ion flux are shown to vary by approximately 20% and 5%, respectively, across the surface of the electrode for the range of conditions investigated in this study.

Bimatoprost for eyelash growth in Japanese subjects: two multicenter controlled studies

BACKGROUND

Bimatoprost 0.03% has enhanced eyelash prominence in clinical trials enrolling mostly Caucasian subjects. The studies described in this report evaluated the efficacy and safety of bimatoprost in Japanese subjects with idiopathic and chemotherapy-induced eyelash hypotrichosis.

METHODS

In two multicenter, double-masked, randomized, parallel-group studies (study 1: n=173 [idiopathic]; study 2: n=36 [chemotherapy-induced]), subjects received bimatoprost 0.03% or vehicle applied once daily to the upper eyelid margins. The primary efficacy measure was eyelash prominence measured by Global Eyelash Assessment (GEA) scores. Additional measures were eyelash length, thickness, and darkness, assessed by digital image analysis, and patient satisfaction (Eyelash Satisfaction Questionnaire-9). Safety assessments included adverse-event monitoring and ophthalmic examinations.

RESULTS

Significantly more bimatoprost-treated subjects had at least a one-grade improvement in GEA score from baseline to month 4 compared with vehicle in study 1 (77.3 vs 17.6%; P<0.001) and study 2 (88.9 vs 27.8%; P<0.001). Bimatoprost-treated subjects had significantly greater increases in eyelash length, thickness, and darkness at the primary time point (month 4 in both studies; all P<0.001, study 1; P≤0.04, study 2). The bimatoprost group showed greater subject satisfaction in both studies. The incidence of adverse events was similar in the two groups. Ophthalmic examination showed slightly greater mean reductions in intraocular pressure (IOP) with bimatoprost than with vehicle, and the reductions were within the normal range for daily IOP fluctuations.

CONCLUSION

Bimatoprost 0.03% was shown to be effective and safe in these studies of Japanese subjects with eyelash hypotrichosis.

LEVEL OF EVIDENCE I

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Soft x-ray spectroscopic investigation of Zn doped CuCl produced by pulsed dc magnetron sputtering

We report on a systematic investigation of the electronic properties of UV-light emitting Zn doped CuCl thin films implemented using near edge x-ray absorption fine structures (NEXAFS) and high-resolution x-ray photoemission spectroscopy. A clear shift of the valence band maximum towards higher binding energy by 0.2 ± 0.1 eV was observed in Zn doped CuCl as compared to undoped CuCl. This shift is in correlation with the increase in conductivity measured by the Hall effect measurements. A decrease in the optical band gap of CuCl film is also observed as a function of Zn doping. The profound changes in the full width at half maximum and the gradual disappearance of satellite features of Cu 2p core level photoemission as a function of Zn dopant are attributed to the reduced presence of the surface layer of Cu(2+) species with d(9) configuration in the doped films. These investigations help us to understand the doping mechanisms and underlying physics. The reduced presence of the Cu(2+) related surface layer as a function of Zn doping is also verified using NEXAFS.

Development and validation of RAYDOSE: a Geant4-based application for molecular radiotherapy

We developed and validated a Monte-Carlo-based application (RAYDOSE) to generate patient-specific 3D dose maps on the basis of pre-treatment imaging studies. A CT DICOM image is used to model patient geometry, while repeated PET scans are employed to assess radionuclide kinetics and distribution at the voxel level. In this work, we describe the structure of this application and present the tests performed to validate it against reference data and experiments. We used the spheres of a NEMA phantom to calculate S values and total doses. The comparison with reference data from OLINDA/EXM showed an agreement within 2% for a sphere size above 2.8 cm diameter. A custom heterogeneous phantom composed of several layers of Perspex and lung equivalent material was used to compare TLD measurements of gamma radiation from (131)I to Monte Carlo simulations. An agreement within 5% was found. RAYDOSE has been validated against reference data and experimental measurements and can be a useful multi-modality platform for treatment planning and research in MRT.

Factor VIII Bypassing Activity (FEIBA) assays: standardization and development of the 1st NIBSC Working Standard for FEIBA--results from a collaborative study

Factor-Eight-Inhibitor-Bypassing-Activity (FEIBA) is a bypassing-agent used to control spontaneous bleeding or cover surgical interventions in Haemophiliacs who develop neutralizing antibodies against FVIII/FIX. The market lot-release of FEIBA is dependent on specific clot-based assays, carried out by both the manufacturer and regulatory authorities, relative to manufacturer's in-house standards, which are produced on a small-scale and are replaced frequently. We sought to standardize the FEIBA assay by developing a FEIBA primary standard which would be internationally available in sufficiently large quantities, with a predicted lifetime of many years. A collaborative study involving the manufacturer and three regulatory authorities, was carried out in which a candidate material, sample B (06/172), was calibrated by assays relative to the manufacturer's in-house FEIBA standards (C and D). All laboratories used their routine validated methods (16 APTT-assays, 8 ACTIN-FS-assays and 27 DAPTTIN-assays). Intra-laboratory geometric coefficients of variation (GCVs) for candidate B ranged from 3% to 29% (GCVs <9% from majority of labs). Assessment of inter-laboratory variability gave overall GCV values of 6.9% and 4.4% relative to standards C and D, respectively, for all methods. There was good agreement in potency estimation between laboratories using each of the three methods, with the overall potencies by the three methods differing by less than 10% of the overall mean, giving an overall combined potency of 28.0 units per ampoule. All participants agreed that candidate B (06/172) be established as the 1st NIBSC Working Standard for FEIBA with an assigned potency of 28.0 units per ampoule, based on combined results for both methods, relative to either standard C or D.

Using estimates of metal bioavailability in the soil and genetic variation of allozymes to investigate heavy metal tolerance in the earthworm Eisenia fetida (Oligochaeta)

In a recent study, we showed that the earthworm species Eisenia fetida, inhabiting an extremely high metal polluted compost heap on a wine farm, did not have elevated body loads of the metals but exhibited genotoxic tolerance when exposed to Cd in the laboratory (Voua Otomo and Reinecke, 2010). To unravel the mechanism behind the surprisingly low metal body burdens on one hand and genotoxic tolerance on the other hand, we investigated the estimated bioavailability of these metals (Cu, Zn, Pb and Cd) using sequential extraction methods with CaCl(2) and di-ethylene-triamine-pentaacetic acid (DTPA) and allozyme polymorphism in this field population, a laboratory control as well as a long-term Cd exposed population. The amounts of mobile (extracted with CaCl(2)) and mobilizable (extracted with DTPA) metals in relation to the total (extracted with nitric acid) metals were all below 0.05% for all four metals, suggesting low availability for uptake. The low availability of these metals could not be explained by physico-chemical properties of soil but by the phenomenon of aging of the metals. There was no difference in allozyme frequency between metal tolerant and non-metal tolerant populations of E. fetida. This suggested that the tolerance found in earlier studies could be a mere physiological adaptation.

Development of a real time monitor and multivariate method for long term diagnostics of atmospheric pressure dielectric barrier discharges: application to He, He/N2, and He/O2 discharges

In this paper we present the development and application of a real time atmospheric pressure discharge monitoring diagnostic. The software based diagnostic is designed to extract latent electrical and optical information associated with the operation of an atmospheric pressure dielectric barrier discharge (APDBD) over long time scales. Given that little is known about long term temporal effects in such discharges, the diagnostic methodology is applied to the monitoring of an APDBD in helium and helium with both 0.1% nitrogen and 0.1% oxygen gas admixtures over periods of tens of minutes. Given the large datasets associated with the experiments, it is shown that this process is much expedited through the novel application of multivariate correlations between the electrical and optical parameters of the corresponding chemistries which, in turn, facilitates comparisons between each individual chemistry also. The results of these studies show that the electrical and optical parameters of the discharge in helium and upon the addition of gas admixtures evolve over time scales far longer than the gas residence time and have been compared to current modelling works. It is envisaged that the diagnostic together with the application of multivariate correlations will be applied to rapid system identification and prototyping in both experimental and industrial APDBD systems in the future.

Association of exposure to diabetes in utero with adiposity and fat distribution in a multiethnic population of youth: the Exploring Perinatal Outcomes among Children (EPOCH) Study

AIMS/HYPOTHESIS

To evaluate whether exposure to maternal gestational diabetes (GDM) is associated with adiposity and fat distribution in a multiethnic population of children.

METHODS

Retrospective cohort study of 82 children exposed to maternal GDM and 379 unexposed youths 6-13 years of age with measured BMI, waist circumference, skinfold thickness, and visceral and subcutaneous abdominal fat.

RESULTS

Exposure to maternal GDM was associated with higher BMI (p = 0.02), larger waist circumference (p = 0.004), more subcutaneous abdominal fat (p = 0.01) and increased subscapular to triceps skinfold thickness ratio (p = 0.01) in models adjusted for age, sex, race/ethnicity and Tanner stage. Adjustment for socioeconomic factors, birthweight and gestational age, maternal smoking during pregnancy and current diet and physical activity did not influence associations; however, adjustment for maternal pre-pregnancy BMI attenuated all associations.

CONCLUSIONS/INTERPRETATION

Exposure to maternal GDM is associated with increased overall and abdominal adiposity, and a more central fat distribution pattern in 6- to 13-year-old youths from a multi-ethnic population, providing further support for the fetal overnutrition hypothesis.

Calibration of human coagulation factor VIII concentrate Ph. Eur. BRP Batch 4 for use in potency assays

The European Pharmacopoeia Biological Reference Preparation (Ph. Eur. BRP) Batch 4 was established as an international common working standard for potency determination of human coagulation factor VIII (FVIII) preparations to replace the dwindling stocks of the BRP Batch 3, the current European standard. Similarly, stocks of the current World Health Organisation 7th International Standard (WHO 7th IS) were also running low. Therefore a project was jointly organised by the European Directorate for the Quality of Medicines & HealthCare (EDQM, Council of Europe) and the National Institute for Biological Standards and Control (NIBSC, UK) in order to replace both standards concomitantly. The potency of the BRP Batch 4 was assigned during an international collaborative study involving 38 laboratories with reference to the WHO 7th IS and the BRP Batch 3. Four candidate materials, 2 plasma-derived (samples A and C) and 2 recombinant (samples B and D) have been evaluated, sample C being the specific candidate for the replacement of the BRP Batch 3. Participants were instructed to perform 8 independent assays following their own routine validated methods, by either the one-stage clotting assay or the chromogenic assay, or both. Laboratories returned 22 data sets for the clotting assay and 30 data sets for the chromogenic assay. This publication reports the results obtained with both assays but only the results of the chromogenic assay are highlighted in the conclusions, as it is the assay prescribed by the European Pharmacopoeia. Data were analysed separately for both assays. The consensus potency value was calculated as the unweighted geometric mean of the unweighted geometric means of each individual laboratory. For sample C, there was a significant difference in potency estimate between the chromogenic and the clotting assay. It was therefore not possible to reconcile both results. The chromogenic potencies however were in very good agreement being 10.4 IU/ampoule (n = 30), when assessed against both standards. The inter-laboratory geometric coefficient of variation (GCV) was 4.8 % and 7.1 % against the WHO 7th IS and the BRP Batch 3 respectively. The Ph. Eur. BRP Batch 4 is a freeze-dried, plasma-derived concentrate. The material was filled in approximately 20,000 ampoules and lyophilised. The final residual water content is 0.33 %. Based on accelerated degradation studies, the stability of the material is suitable for a reference preparation. The candidate Ph. Eur. BRP Batch 4 was adopted at the 136th session of the European Pharmacopoeia Commission in March 2010. The standard will be available from the EDQM with the catalogue number H0920000 upon exhaustion of the current batch.

Evaluation of novel particles as an inhalation system for GLP-1

AIM

The feasibility of administering native glucagon-like peptide 1 (GLP-1) as GLP-1 Technosphere Inhalation Powder for diabetes therapy has been demonstrated in a rat model.

METHODS

GLP-1 Technosphere Inhalation Powders containing 5, 10 and 15% GLP-1 were prepared and administered to healthy female Sprague-Dawley rats and to male Zucker diabetic obese rats. Rats received a single dose of GLP-1 Technosphere Powder by pulmonary insufflation. GLP-1 pharmacokinetic and pharmacodynamic responses were measured.

RESULTS

Maximum circulating GLP-1 concentrations were achieved at approximately 10 min after dosing with detectable levels at 40 min. In a food consumption study, Sprague-Dawley rats receiving GLP-1 Technosphere Powder once-daily consumed less food than control rats for up to 24 h after dosing. Cumulative food consumption was decreased approximately 10% after 78 h. In an intraperitoneal glucose tolerance test, Zucker diabetic fatty rats receiving 2 mg GLP-1 Technosphere Powder (0.3 mg GLP-1) by pulmonary insufflation exhibited lower glucose concentrations and higher insulin concentrations than control rats. Pancreatic evaluations showed no differences in apoptotic index or cell proliferation of beta-cells. In addition, a dose-related increase in insulin expression within the pancreas was observed.

CONCLUSIONS

These data demonstrate the feasibility of administering native GLP-1 as GLP-1 Technosphere Inhalation Powder for diabetes therapy.

Handheld Flyback driven coaxial dielectric barrier discharge: Development and characterization

The development of a handheld single and triple chamber atmospheric pressure coaxial dielectric barrier discharge driven by Flyback circuitry for helium and argon discharges is described. The Flyback uses external metal-oxide-semiconductor field-effect transistor power switching technology and the transformer operates in the continuous current mode to convert a continuous dc power of 10-33 W to generate a 1.2-1.6 kV 3.5 micros pulse. An argon discharge breakdown voltage of approximately 768 V is measured. With a 50 kHz, pulse repetition rate and an argon flow rate of 0.5-10 argon slm (slm denotes standard liters per minute), the electrical power density deposited in the volume discharge increases linearly at a rate of 75+/-20% mW/cm(3) per 1 slm of gas. Electrical power transfer efficiency between the secondary Flyback coil and the discharge volume increases from 0.1% to 0.65%. Neutral argon gas forced convection analysis yields a similar energy loss rate to the electrical discharge process. Optical emission spectroscopy studies of the expanding discharge plume into ambient air reveal that the air climatically controls the plume chemistry to produce an abundance of neutral argon atoms and molecular nitrogen.

Determination of blood pressure percentiles in normal-weight children: some methodological issues

Blood pressure in children has consistently been related to adult blood pressure, with implications for long-term prevention of cardiovascular disease. The epidemic of obesity in children has resulted in corresponding increases in childhood blood pressure. In this paper, the authors develop norms for childhood blood pressure among normal-weight children (body mass index <85th percentile based on Centers for Disease Control and Prevention guidelines) as a function of age, sex, and height, using data from 49,967 children included in the database of the National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents (the Pediatric Task Force). The authors considered three types of models for pediatric blood pressure data, including polynomial regression, restricted cubic splines, and quantile regression, with the latter providing the best fit. The sex-specific norms presented here are a nonlinear function of both age and height and are generally slightly lower than previously developed norms based on Pediatric Task Force data including both normal-weight and overweight children.

Access to specialist gastroenterology care in Canada: comparison of wait times and consensus targets

BACKGROUND

Monitoring wait times and defining targets for care have been advocated to improve health care delivery related to cancer, heart, diagnostic imaging, joint replacements and sight restoration. There are few data on access to care for digestive diseases, although they pose a greater economic burden than cancer or heart disease in Canada. The present study compared wait times for specialist gastroenterology care with recent, evidence-based, consensus-defined benchmark wait times for a range of digestive diseases.

METHODS

Total wait times from primary care referral to investigation were measured for seven digestive disease indications by using the Practice Audit in Gastroenterology program, and were benchmarked against consensus recommendations.

RESULTS

Total wait times for 1903 patients who were undergoing investigation exceeded targets for those with probable cancer (median 26 days [25th to 75th percentiles eight to 56 days] versus target of two weeks); probable inflammatory bowel disease (101 days [35 to 209 days] versus two weeks); documented iron deficiency anemia (71 days [19 to 142 days] versus two months); positive fecal occult blood test (73 days [36 to 148 days] versus two months); dyspepsia with alarm symptoms (60 days [23 to 140 days] versus two months); refractory dyspepsia without alarm symptoms (126 days [42 to 225 days] versus two months); and chronic constipation and diarrhea (141 days [68 to 264 days] versus two months). A minority of patients were seen within target times: probable cancer (33% [95% CI 20% to 47%]); probable inflammatory bowel disease (12% [95% CI 1% to 23%]); iron deficiency anemia (46% [95% CI 37% to 55%]); positive occult blood test (41% [95% CI 28% to 54%]); dyspepsia with alarm symptoms (51% [95% CI 41% to 60%]); refractory dyspepsia without alarm symptoms (33% [95% CI 19% to 47%]); and chronic constipation and diarrhea (21% [95% CI 14% to 29%]).

DISCUSSION

Total wait times for the seven indications exceeded the consensus targets; 51% to 88% of patients were not seen within the target wait time. Multiple interventions, including adoption of evidence-based management guidelines and provision of economic and human resources, are needed to ensure appropriate access to digestive health care in Canada. Outcomes can be evaluated by the 'point-of-care', practice audit methodology used for the present study.