Creation of Porous, Perfusable Microtubular Networks for Improved Cell Viability in Volumetric Hydrogels

The creation of large, volumetric tissue-engineered constructs has long been hindered due to the lack of effective vascularization strategies. Recently, 3D printing has emerged as a viable approach to creating vascular structures; however, its application is limited. Here, we present a simple and controllable technique to produce porous, free-standing, perfusable tubular networks from sacrificial templates of polyelectrolyte complex and coatings of salt-containing citrate-based elastomer poly(1,8-octanediol-co-citrate) (POC). As demonstrated, fully perfusable and interconnected POC tubular networks with channel diameters ranging from 100 to 400 μm were created. Incorporating NaCl particulates into the POC coating enabled the formation of micropores (∼19 μm in diameter) in the tubular wall upon particulate leaching to increase the cross-wall fluid transport. Casting and cross-linking gelatin methacrylate (GelMA) suspended with human osteoblasts over the free-standing porous POC tubular networks led to the fabrication of 3D cell-encapsulated constructs. Compared to the constructs without POC tubular networks, those with either solid or porous wall tubular networks exhibited a significant increase in cell viability and proliferation along with healthy cell morphology, particularly those with porous networks. Taken together, the sacrificial template-assisted approach is effective to fabricate tubular networks with controllable channel diameter and patency, which can be easily incorporated into cell-encapsulated hydrogels or used as tissue-engineering scaffolds to improve cell viability.

Genome-based epidemiology and antimicrobial resistance of Neisseria gonorrhoeae in Spain: A prospective multicentre study

BACKGROUND

Whole-genome sequencing (WGS) of Neisseria gonorrhoeae isolates combined with epidemiological and phenotypic data provides better understanding of population dynamics.

AIM

The objective of this study was to investigate the molecular epidemiology of N. gonorrhoeae isolates from three centres in Spain and determine associations of antimicrobial resistance.

METHODS

Genetic characterization was performed in 170 N. gonorrhoeae isolates. WGS was carried out with the HiSeq platform (Illumina). Genome assemblies were submitted to the PubMLST Neisseria database website to determine NG-MAST, MLST and NG-STAR. Antimicrobial resistance genes and point mutations were identified with PubMLST. Phylogenomic comparison was based on whole-genome single nucleotide polymorphism analysis.

RESULTS

Twenty-six MLST, 49 NG-MAST and 41 NG-STAR sequence types were detected, the most prevalent being MLST-ST9363 (27.1%), NG-MAST ST569 (12.4%) and NG-STAR ST193 (14.7%). Phylogenetic analysis identified 13 clusters comprising 69% of the isolates, with two of note: one involved cefixime-resistant isolates from Barcelona presenting a mosaic penA X and belonging to MLST-ST7363 and the other involved azithromycin-resistant isolates from Mallorca that possessed the C2611T mutation in the four 23S rRNA alleles belonging to MLST-ST1901.

CONCLUSION

The population of N. gonorrhoeae is quite heterogeneous in Spain. Our results agree with previous data published in Europe, albeit with some differences in distribution between regions. This study describes the circulation of two gonococcal populations with a specific resistance profile and sequence type in a specific geographic area. WGS is an effective tool for epidemiological surveillance of gonococcal infection and detection of resistance genes.

Effects of grazing platform stocking rate on productivity and profitability of pasture-based dairying in a fragmented farm scenario

The area adjacent to the milking parlor, accessible for grazing by lactating dairy cows (i.e., the grazing platform [GP]), can be limited on fragmented pasture-based dairy farms. Such farms, with a moderate overall farm stocking rate, typically have a much higher stocking rate of dairy cows on the GP. This study quantified the effects of farm fragmentation on milk and herbage production and profitability in a whole-farm systems-scale study over 3 yr (2017-2019). Four systems, each with an overall farm stocking rate of 2.5 cows/ha but with different grazing platform stocking rates (GPSR), were examined. The proportions of the overall farm area within the GP were 100%, 83%, 71%, and 63% in each of the 4 systems, respectively. Hence, the 4 systems had a GPSR of 2.5, 3.0, 3.5, and 4.0 cows/ha. The GP was used for grazing and silage (ensiled herbage) production, and the non-GP portion of each GPSR system was used solely for silage production. Concentrate supplementation per cow was the same across all GPSR systems; approximately 10% of the annual feed budget. All systems were compact spring-calving with 24 cows per system. We discovered a lower proportion of grazed herbage in the diet with higher GPSR. All silage produced on the non-GP areas was required to support higher GPSR on each of the systems. Annual herbage production and milk production per cow were not different between GPSR systems, resulting in similar milk production per hectare of the overall system area. The economic implications of different GPSR on fragmented farms were modeled in 2 scenarios: (1) quantifying the cost associated with different levels of farm area fragmentation; (2) investigating the optimum GPSR on fragmented pasture-based dairy farms, depending on variable criteria. A greater level of farm fragmentation lowered the profitability of pasture-based dairy production. Costs of production increased with higher GPSR and longer distances between GP and non-GP areas. At a fixed GP area, it was most profitable to increase GPSR up to 4 cows/ha on the GP when milk price was high, land rental price was low, and shorter distance existed between GP and non-GP areas.

4-Methylumbelliferone-Functionalized Polyphosphazene and Its Assembly into Biocompatible Fluorinated Nanocoatings with Selective Antiproliferative Activity

Advanced multifunctional biomaterials are increasingly relying on clinically dictated patterns of selectivity against various biological targets. Integration of these frequently conflicting features into a single material surface may be best achieved by combining various complementary methodologies. Herein, a drug with a broad spectrum of activity, i.e., 4-methylumbelliferone (4-MU), is synthetically multimerized into water-soluble anionic macromolecules with the polyphosphazene backbone. The polymer structure, composition, and solution behavior are studied by ¹H and ³¹P NMR spectroscopy, size-exclusion chromatography, dynamic light scattering, and UV and fluorescence spectrophotometry. To take advantage of the clinically proven hemocompatibility of fluorophosphazene surfaces, the drug-bearing macromolecule was then nanoassembled onto the surface of selected substrates in an aqueous solution with fluorinated polyphosphazene of the opposite charge using the layer-by-layer (LbL) technique. Nanostructured 4-MU-functionalized fluoro-coatings exhibited a strong antiproliferative effect on vascular smooth muscle cells (VSMCs) and fibroblasts with no cytotoxicity against endothelial cells. This selectivity pattern potentially provides the opportunity for highly desirable fast tissue healing while preventing the overgrowth of VSMCs and fibrosis. Taken together with the established in vitro hemocompatibility and anticoagulant activity, 4-MU-functionalized fluoro-coatings demonstrate potential for applications as restenosis-resistant coronary stents and artificial joints.

Cohort profile: the ESC EURObservational Research Programme Non-ST-segment elevation myocardial infraction (NSTEMI) Registry

AIMS

The European Society of Cardiology (ESC) EURObservational Research Programme (EORP) Non-ST-segment elevation myocardial infarction (NSTEMI) Registry aims to identify international patterns in NSTEMI management in clinical practice and outcomes against the 2015 ESC Guidelines for the management of acute coronary syndromes in patients presenting without ST-segment-elevation.

METHODS AND RESULTS

Consecutively hospitalised adult NSTEMI patients (n = 3620) were enrolled between 11 March 2019 and 6 March 2021, and individual patient data prospectively collected at 287 centres in 59 participating countries during a two-week enrolment period per centre. The registry collected data relating to baseline characteristics, major outcomes (in-hospital death, acute heart failure, cardiogenic shock, bleeding, stroke/transient ischaemic attack, and 30-day mortality) and guideline-recommended NSTEMI care interventions: electrocardiogram pre- or in-hospital, pre-hospitalization receipt of aspirin, echocardiography, coronary angiography, referral to cardiac rehabilitation, smoking cessation advice, dietary advice, and prescription on discharge of aspirin, P2Y12 inhibition, angiotensin converting enzyme inhibitor (ACEi)/angiotensin receptor blocker (ARB), beta-blocker, and statin.

CONCLUSION

The EORP NSTEMI Registry is an international, prospective registry of care and outcomes of patients treated for NSTEMI, which will provide unique insights into the contemporary management of hospitalised NSTEMI patients, compliance with ESC 2015 NSTEMI Guidelines, and identify potential barriers to optimal management of this common clinical presentation associated with significant morbidity and mortality.

45 INTERPROFESSIONAL EDUCATION AND COLLABORATIVE PRACTICE IN FRAIL OLDER PERSONS’ CARE

Background

Frail older adults present with complex care needs. Inter-Professional Education (IPE) is a means of creating a practice-ready workforce to improve patient safety and healthcare outcomes. A Steering Group was established comprised of acute and community clinicians, members of the Health Service Executive, service user, students and members of all Schools in the College of Medicine and Health in an Irish University (Medicine, Nursing and Midwifery, Pharmacy, Public Health, Clinical Therapies and Dentistry) to evaluate the effectiveness of IPE. A workshop dedicated to the management of frail older adults occurred for multidisciplinary healthcare students as part of a suite of three IPE workshops.

Methods

The validated ‘Interprofessional Collaborative Competencies Attainment Survey’ (ICCAS) evaluated student views of IPE pre- & post-workshop. This workshop involved a case-based study and facilitated discussion with involvement of frail older adult service users. One service user was in a rehabilitation unit post hospital admission, the other was living well at home. Their participation occurred using an online platform, supported by a consultant geriatrician in the rehabilitation unit and a relative for the home-based service user.

Results

Student scores on the six subscales of the ICCAS (communication, collaboration, roles and responsibilities, collaborative patient-centred approach, conflict management and team functioning) were compared. Scores in all categories achieved statistically significant increases after completion of the IPE workshop. The greatest positive change was observed in collaborative patient-centred approach with pre-workshop scores increasing from a mean of 2.61 to 4.25 (p<0.05).

Conclusion

This initiative explored the inclusion of a frail older adult workshop in the higher education setting. Older adults had an opportunity to share their lived experiences. Evaluation of this IPE initiative will inform future IPE activities to be incorporated into undergraduate education programmes. Similar IPE models can be replicated nationally to enable and enhance team-based working and integrated care.

Promoting the key moments of hand hygiene in a Targeted Hygiene intervention at COP26

 

The COP26 conference in Glasgow, November 2021 presented a unique public health challenge in the midst of the COVID-19 pandemic. With 38,457 delegates attending, this international event posed a risk for SARS-CoV-2 infection. We used Targeted Hygiene theory to carry out a large event risk assessment process that focused on how spaces were used, referred to evidence from scientific literature, and identified key moments for surface and hand hygiene interventions. We relied on behavioural science evidence to optimize hand hygiene compliance at the event. To do so, we secured the opportunity to use hand sanitizer by determining the most suitable locations for over 500 hand sanitizing stations. To further motivate uptake of personal hygiene, kits were provided for each delegate with hygiene messaging to improve knowledge of the importance of hand hygiene in breaking the chain of infection. A COP26-branded face covering, personal hand gel and wipes were provided in the pack. Training and cleaning protocols centred on Targeted Hygiene were developed for cleaning teams to implement. Compliance monitoring through observation and daily real-time reporting of over 250 adenosine triphosphate (ATP) checks on just-cleaned surfaces provided reassurance for public health agencies that our Targeted Hygiene approach was effective.

The messaging and cleaning interventions were carried out for the duration of the COP26 conference. The number of individuals officially affiliated with COP26 that tested positive was ∼2 in 1,000 as compared to ∼11-12 in 1,000 individuals in Scotland during the same period (6-13 November 2021 as reported by Public Health Scotland). Whilst no single control can be attributed to this achievement, effective hand and surface hygiene interventions contributed by helping to break the chain of infection. This risk-based approach to Targeted Hygiene serves as a blueprint for effective, sustainable and measurable nonpharmaceutical interventions at large scale events.

Key messages

• To mitigate risk of infection at COP26, key moments for surface and hand hygiene were identified and emphasized in cleaning protocols and education.

• Using a risk-based approach to Targeted Hygiene serves as a blueprint for effective, sustainable and measurable nonpharmaceutical interventions at large scale events such as COP26.

Epidemiology and impact of frailty in patients with atrial fibrillation in Europe

BACKGROUND

Frailty is a medical syndrome characterised by reduced physiological reserve and increased vulnerability to stressors. Data regarding the relationship between frailty and atrial fibrillation (AF) are still inconsistent.

OBJECTIVES

We aim to perform a comprehensive evaluation of frailty in a large European cohort of AF patients.

METHODS

A 40-item frailty index (FI) was built according to the accumulation of deficits model in the AF patients enrolled in the ESC-EHRA EORP-AF General Long-Term Registry. Association of baseline characteristics, clinical management, quality of life, healthcare resources use and risk of outcomes with frailty was examined.

RESULTS

Among 10,177 patients [mean age (standard deviation) 69.0 (11.4) years, 4,103 (40.3%) females], 6,066 (59.6%) were pre-frail and 2,172 (21.3%) were frail, whereas only 1,939 (19.1%) were considered robust. Baseline thromboembolic and bleeding risks were independently associated with increasing FI. Frail patients with AF were less likely to be treated with oral anticoagulants (OACs) (odds ratio 0.70, 95% confidence interval 0.55-0.89), especially with non-vitamin K antagonist OACs and managed with a rhythm control strategy, compared with robust patients. Increasing frailty was associated with a higher risk for all outcomes examined, with a non-linear exponential relationship. The use of OAC was associated with a lower risk of outcomes, except in patients with very/extremely high frailty.

CONCLUSIONS

In this large cohort of AF patients, there was a high burden of frailty, influencing clinical management and risk of adverse outcomes. The clinical benefit of OAC is maintained in patients with high frailty, but not in very high/extremely frail ones.

Long COVID syndrome and the lung: how long will it last?

The prevalence and duration of the long-term respiratory complications of COVID-19 infection remains to be elucidated. This short commentary reports on recently published studies in patients post-acute COVID-19 infection in terms of symptom prevalence, physiological and radiological sequela and where only symptoms are present despite investigation. Pulmonary function testing, 6-min walk tests, computed tomography chest and more advanced imaging modalities have been incorporated to reveal the underlying pathophysiology that cause such disabling symptoms in patient with post-acute COVID-9 syndrome (PACS). PACS has a serious impact on people's ability to return to work, affecting the physical, mental, social sphere and with significant healthcare and general economic consequences for them, their families and society.

Adherence to non-pharmaceutical interventions for COVID-19: a national survey

Background

The global Covid-19 pandemic response depends heavily on non-pharmaceutical interventions to protect population health. This aim of this study was to provide insights into levels and determinants of adherence to travel restrictions and wearing of face coverings during the early phase of the pandemic response in Ireland.

Methods

A series of four cross-sectional surveys were administered through random digit dialling of mobile and landline numbers during May-June 2020. Questions were asked about compliance with local travel restrictions and where relevant, the reasons for travel. A question on mask use was added to the final wave of data collection.

Results

Overall, across the four waves, 73.4% reported adhering to the travel restrictions and these levels were maintained over time (wave 1: 72.1%, wave 2: 73.7%, wave 3: 67.3%, wave 4: 79.7%) and were broadly similar across different socioeconomic groups. Higher proportions reported travelling for non-exempt reasons over time particularly in the final wave of data collection including exercise (from 3% in wave 1, 5% in wave 2 up to 8% in waves 3 and 4) and recreational or social activities (2% in waves 1 and 2, 4% in wave 3, up to 15% by wave 4). Overall, over two-thirds of respondents reported use of masks in the final wave, (72% of women, 65% of men) with shops or supermarkets the most common place of use. Among primary respondents, older age (Age 70+ vs. 18k-44, OR 3.2 [2.4-4.3]), attending higher education (attending vs. completed third level OR 2.2 [ 1.6-3.0]) and female gender (OR 1.2 [1.1-1.4]) were independently associated with compliance with travel restrictions.

Conclusions

The findings demonstrate high levels of adherence to travel restrictions during the early stages of the emerging COVID-19 pandemic, albeit with a modest trend towards reduced compliance over time. There was a high uptake of mask use in advance of relevant national guidance.

TRAFIC: statistical design and analysis plan for a pragmatic early phase 1/2 Bayesian adaptive dose escalation trial in rheumatoid arthritis

Background

Adaptive model-based dose-finding designs have demonstrated advantages over traditional rule-based designs but have increased statistical complexity but uptake has been slow especially outside of cancer trials. TRAFIC is a multi-centre, early phase trial in rheumatoid arthritis incorporating a model-based design.

Methods

A Bayesian adaptive dose-finding phase I trial rolling into a single-arm, single-stage phase II trial. Model parameters for phase I were chosen via Monte Carlo simulation evaluating objective performance measures under clinically relevant scenarios and incorporated stopping rules for early termination. Potential designs were further calibrated utilising dose transition pathways.

Discussion

TRAFIC is an MRC-funded trial of a re-purposed treatment demonstrating that it is possible to design, fund and implement a model-based phase I trial in a non-cancer population within conventional research funding tracks and regulatory constraints. The phase I design allows borrowing of information from previous trials, all accumulated data to be utilised in decision-making, verification of operating characteristics through simulation, improved understanding for management and oversight teams through dose transition pathways. The rolling phase II design brings efficiencies in trial conduct including site and monitoring activities and cost.

TRAFIC is the first funded model-based dose-finding trial in inflammatory disease demonstrating that small phase I/II trials can have an underlying statistical basis for decision-making and interpretation.

Trial registration

Trials Registration: ISRCTN, ISRCTN36667085. Registered on September 26, 2014.

Dementia palliative care: A multi-site survey of long term care STAFF'S education needs and readiness to change

Many people with dementia reside in long-term care, where limited staff knowledge of dementia palliative care has been identified, along with poor awareness that a palliative approach can assist in identifying unmet care needs. Evidence-based guidance in palliative care for people with dementia is available however, implementing this guidance requires staff engagement and a tailored educational approach. This pre-implementation situational analysis informed a tailored staff education intervention to support the implementation of national guidance on dementia palliative care in long term care. Using a cross-sectional study design, underpinned by the Consolidated Framework for Implementation Research, survey data were collected on site profile, staff demographics, learning needs, and readiness-to change at three residential care sites for older people in Ireland. In total, 69 staff (predominantly nurses and healthcare attendants) completed the surveys. Medication management and management of pain were the most frequently identified learning needs. Staff were confident in their ability to implement change but de-motivation and powerlessness were substantial factors as only one-third of staff were "ready for change". Staffing levels, managing risk during change and perceived reluctance in others were common barriers. These results informed an educational intervention to address the specific care context, staff learning needs and barriers to change prior to implementation.

Establishing nationally representative benchmarks of farm-gate nitrogen and phosphorus balances and use efficiencies on Irish farms to encourage improvements

Agriculture faces considerable challenges of achieving more sustainable production that minimises nitrogen (N) and phosphorus (P) losses and meets international obligations for water quality and greenhouse gas emissions. This must involve reducing nutrient balance (NB) surpluses and increasing nutrient use efficiencies (NUEs), which could also improve farm profitability (a win-win). To set targets and motivate improvements in Ireland, nationally representative benchmarks were established for different farm categories (sector, soil group and production intensity). Annual farm-gate NBs (kg ha^-1) and NUEs (%) for N and P were calculated for 1446 nationally representative farms from 2008 to 2015 using import and export data collected by the Teagasc National Farm Survey (part of the EU Farm Accountancy Data Network). Benchmarks for each category were established using quantile regression analysis and percentile rankings to identify farms with the lowest NB surplus per production intensity and highest gross margins (€ ha^-1). Within all categories, large ranges in NBs and NUEs between benchmark farms and poorer performers show considerable room for nutrient management improvements. Results show that as agriculture intensifies, nutrient surpluses, use efficiencies and gross margins increase, but benchmark farms minimise surpluses to relatively low levels (i.e. are more sustainable). This is due to, per ha, lower fertiliser and feed imports, greater exports of agricultural products, and for dairy, sheep and suckler cattle, relatively high stocking rates. For the ambitious scenario of all non-benchmark farms reaching the optimal benchmark zone, moderate reductions in farm nutrient surpluses were found with great improvements in profitability, leading to a 31% and 9% decrease in N and P surplus nationally, predominantly from dairy and non-suckler cattle. The study also identifies excessive surpluses for each level of production intensity, which could be used by policy in setting upper limits to improve sustainability.

AB0356 TARGETING THE RHEUMATOID ARTHRITIS SYNOVIAL FIBROBLAST VIA CYCLIN DEPENDENT KINASE INHIBITION (TRAFIC): A PHASE 1B STUDY TO DETERMINE THE MAXIMUM TOLERATED DOSE OF SELICICLIB FOR REPURPOSING IN RHEUMATOID ARTHRITIS

Background:

Current rheumatoid arthritis (RA) therapeutics target immune inflammation and are subject to ceiling effects, with non-response observed in a third of recipients together with low remission rates. Synovial fibroblasts (SFs) are stromal cells not yet targeted in RA, whose hyperplastic and proliferative properties drive inflammation and tissue destruction. Seliciclib (R-roscovitine) is an orally available cyclin-dependent kinase (CDK) inhibitor that suppresses SF proliferation and ameliorates inflammatory arthritis in rodents.

Objectives:

To determine the maximum tolerated dose (MTD) of seliciclib in patients with active RA despite anti-TNF, with or without background conventional disease modifying anti-rheumatic drugs (cDMARDs). Safety and pharmacokinetics (PK) were also evaluated.

Methods:

A restricted, one-stage Bayesian continual reassessment method (CRM) determined MTD based on a target dose-limiting toxicity (DLT) probability of 35%. RA patients (DAS28 ≥3.2) were recruited sequentially to cohorts of 3 subjects each. Cohort 1 received 400mg seliciclib daily for 4 consecutive days each week for 4 weeks, added to existing therapy. Each subsequent cohort received a dose determined by the toxicity-based CRM algorithm, calculated upon conclusion of the previous cohort. Safety was assessed through adverse event (AE) monitoring. Associations with relevant PK parameters were sought.

Results:

15 anti-TNF recipients were enrolled, 10 of whom were also taking cDMARDs (median DAS28 4.9). Application of the CRM algorithm prompted one dose increment during the study (to 600mg for cohort 2), but reversion to 400mg for subsequent cohorts (Figure 1A). After treatment of 5 cohorts, 400mg was determined the MTD, with a DLT probability of 0.35 (CI 0.18-0.52; Figure 1B). 6 patients experienced DLTs, of which two were classified as serious AEs (SAEs) in keeping with the safety profile of seliciclib; these are summarised in Table 1. Of 43/65 total AEs reported at any dose that didnotcontribute to a DLT, 26 were possibly, probably or definitely related to seliciclib; 19 of these 26 were mild, 7 moderate and none severe. The most frequent AE was mild nausea. No relationship of safety and/or tolerability with concomitant cDMARD use or PK was seen.

Table 1.

Characteristics of patients who developed HZ at initiation of baricitinib

DLTSeliciclib dose (mg)Doses receivedContributing AEsContributing SAEsDescriptionOutcomeA1400830Constipation, N+V, liver injury; fatigue.Resolved2600430Constipation, N+V.Resolved3600101BFever, N+V, renal injury.Resolved4400831BConstipation, N+V, jaundice, liver injury.Resolved5400840Fever, dizziness, liver injury.Resolved6400890Dizziness, N+V, liver injury, bilirubin rise.Persistent AST rise

Conclusion:

The MTD of seliciclib has been defined for RA. No unexpected safety concerns were identified to preclude ongoing evaluation in patients, which focuses on clinical, radiological and biological indicators of efficacy.

Disclosure of Interests:

Arthur Pratt Grant/research support from: Pfizer, GlaxoSmithKlein, Stefan Siebert Grant/research support from: BMS, Boehringer Ingelheim, Celgene, GlaxoSmithKline, Janssen, Novartis, Pfizer, UCB, Consultant of: AbbVie, Boehringer Ingelheim, Janssen, Novartis, Pfizer, UCB, Speakers bureau: AbbVie, Celgene, Janssen, Novartis, Michael Cole: None declared, Deborah Stocken: None declared, Stephen Kelly: None declared, Muddassir Shaikh: None declared, Amy Cranston: None declared, Miranda Morton: None declared, Jennifer Walker: None declared, Sheelagh Frame Employee of: Cyclacel Ltd., Wan-fai Ng: None declared, Chris Buckley Consultant of: Janssen, Pfizer, GSK, Galapagos, Gillead, Iain McInnes Grant/research support from: Bristol-Myers Squibb, Celgene, Eli Lilly and Company, Janssen, and UCB, Consultant of: AbbVie, Bristol-Myers Squibb, Celgene, Eli Lilly and Company, Gilead, Janssen, Novartis, Pfizer, and UCB, Andrew Filer: None declared, John D Isaacs Consultant of: AbbVie, Bristol-Myers Squibb, Eli Lilly, Gilead, Janssen, Merck, Pfizer, Roche

Screening Nitrate in Forages with a Test Strip: Collaborative Study

A collaborative study was conducted for screening nitrate in forages with a commercially available test strip. The method involves extracting a finely ground sample with deionized water. The test strip is dipped in the sample extract. The color of the reaction zone on the test strip changes from white to pink or purple depending on the nitrate concentration in sample extract. The nitrate present in the extract is determined by comparing the color of the test strip to the color scale on the test strip container. Six blind quintuplicates of forage samples were analyzed by 20 collaborators. Nitrate concentrations in forage samples tested ranged from <1000 ppm nitrate to >10 000 ppm nitrate on dry matter basis. Each collaborator was asked to assign each sample to one of the 4 following nitrate concentration ranges: (1) <1000 ppm, (2) 1000 to 5000 ppm, (3)>5000 ppm to 10 000 ppm, and (4) >10 000 ppm. Nineteen of 20 collaborators reported results. Results from 2 laboratories were rejected as outliers by inspection and χ2 test. Sensitivity rates (p+) ranged from 0.965 to 0.998, with standard errors of 0.006 to 0.16. Specificity rates (p−) ranged from 0.991 to 0.997 for the 4 ranges, with standard errors of 0.003 to 0.006. False-positive rates (pf+) ranged from 0.006 to 0.046, with standard errors of 0.006 to 0.025. False-negative rates (pf−) ranged from 0.003 to 0.007, with standard errors of 0.003 to 0.006. Screening nitrate in forages with a test strip has been adopted first action by AOAC INTERNATIONAL.

Characterization of a prevascularized biomimetic tissue engineered scaffold for bone regeneration

Significant bone loss due to disease or severe injury can result in the need for a bone graft, with over 500,000 procedures occurring each year in the United States. However, the current standards for grafting, autografts and allografts, can result in increased patient morbidity or a high rate of failure respectively. An ideal alternative would be a biodegradable tissue engineered graft that fulfills the function of bone while promoting the growth of new bone tissue. We developed a prevascularized tissue engineered scaffold of electrospun biodegradable polymers PLLA and PDLA reinforced with hydroxyapatite, a mineral similar to that found in bone. A composite design was utilized to mimic the structure and function of human trabecular and cortical bone. These scaffolds were characterized mechanically and in vitro to determine osteoinductive and angioinductive properties. It was observed that further reinforcement is necessary for the scaffolds to mechanically match bone, but the scaffolds are successful at inducing the differentiation of mesenchymal stem cells into mature bone cells and vascular endothelial cells. Prevascularization was seen to have a positive effect on angiogenesis and cellular metabolic activity, critical factors for the integration of a graft.

Mechanical and biological evaluation of a hydroxyapatite-reinforced scaffold for bone regeneration

With over 500,000 bone grafting procedures performed annually in the United States, the advancement of bone regeneration technology is at the forefront of medical research. Many tissue-engineered approaches have been explored to develop a viable synthetic bone graft substitute, but a major challenge is achieving a load-bearing graft that appropriately mimics the mechanical properties of native bone. In this study, sintered hydroxyapatite (HAp) was used to structurally reinforce a scaffold and yield mechanical properties comparable to native bone. HAp was packed into a cylindrical framework and processed under varying conditions to maximize its mechanical properties. The resulting HAp columns were further tested in a 6-week degradation study to determine their physical and mechanical response. The cellular response of sintered HAp was determined using a murine preosteoblast cell line, MC3T3-E1. Cell viability and morphology were studied over a one-week period and MC3T3-E1 differentiation was determined by measuring the alkaline phosphatase levels. Finite element analysis was used to determine the columns' geometric configuration and arrangement within our previously developed composite bone scaffold. It was determined that incorporating four cylindrical HAp columns, fabricated under 44 MPa of pressure and sintered at 1200°C for 5 hr, led to load-bearing properties that match the yield strength of native whole bone. These preliminary results indicate that the incorporation of a mechanically enhanced HAp structural support system is a promising step toward developing one of the first load-bearing bone scaffolds that can also support cell proliferation and osteogenic differentiation. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 732-741, 2019.

Enhancing predicted fluoride varnish efficacy and post-treatment compliance by means of calcium-containing gummy bears

OBJECTIVES

This study determined whether consumption of calcium-containing gummies prior to fluoride varnish application enhances plaque fluoride retention and compliance with post-varnish application instructions.

METHODS

The present study followed a multi-center, parallel, randomized, and laboratory analyst-blind design. Following IRB approval, parent consent and child assent, 44 subjects (7-12 years), were randomized to either gummy or no-gummy study groups. A baseline plaque sample was obtained after a wash-out period. Fluoride varnish (5% NaF) was applied; subjects in the gummy group received two calcium-containing gummies prior to varnish application. Subjects were given two questionnaires to complete (subject and parent) to investigate adherence to post-treatment instructions. Three days later, a second plaque sample was obtained. Plaque was analyzed for plaque fluid and solid fluoride concentrations. Fluoride data were analyzed using Wilcoxon Rank Sum tests, questionnaire data using Pearson chi-square tests.

RESULTS

Plaque fluid fluoride did not change pre- to post-treatment in the gummy group (mean ± sd: 8.8 ± 5.7 μmol/l vs. 10.0 ± 6.3 μmol/l; p = 0.265) or in the no-gummy group (8.1 ± 4.4 μmol/l vs. 16.1 ± 20.0 μmol/l; p = 0.058). Groups were not different for plaque fluid fluoride pre-treatment (p = 1.000), post-treatment (p = 0.904), or change (p = 0.904). Plaque solid fluoride did not change pre- to post-treatment in the gummy group (0.89 ± 1.10 μmol/g vs. 1.37 ± 1.77 μmol/g; p = 0.073) or in the no-gummy group (0.68 ± 0.77 μmol/g vs. 2.01 ± 5.00 μmol/g; p = 0.190). Groups were not different for plaque solid fluoride pre-treatment (p = 1.000), post-treatment (p = 0.466), or change (p = 0.874). No significant differences were found between groups for questionnaire responses.

CONCLUSION

This study failed to demonstrate an effect of calcium-containing gummies in enhancing plaque fluoride retention.

CLINICAL SIGNIFICANCE

The consumption of calcium-containing gummies prior to fluoride varnish application does not promote greater intra-oral fluoride retention or better adherence to post-treatment instructions.

Using submersible fluorescence sensors to track the removal of organic matter in decentralized wastewater treatment systems (DEWATS) in real time

Decentralized wastewater treatment systems (DEWATS) using anaerobic treatment are increasingly being considered for wastewater treatment with options for non-potable water reuse at the community scale. One challenge for ensuring performance and reliability of DEWATS is the lack of suitable on-site sensors to monitor failure or contamination events. In this study, the aim was to use in situ fluorescence sensors to track the performance of a DEWATS, consisting of an anaerobic baffled reactor (ABR) coupled to anaerobic filter (AF) and constructed wetland (CW) treatment processes. A submersible in situ fluorometer equipped with tryptophan (TRP) and chromophoric dissolved organic matter (CDOM) sensors was deployed in each chamber of the ABR-AF-CW system, and results showed that TRP fluorescence was preferentially removed over CDOM fluorescence throughout the system. Significant relationships between TRP fluorescence and chemical oxygen demand (COD) also suggested that TRP fluorescence could be used as a surrogate for COD and soluble COD concentrations. Strong agreement between results obtained from the 1D in situ fluorometer and those obtained from a 3D benchtop fluorometer lends further support to the use of in situ fluorescence sensors to track DEWATS performance.

Perspectives on the underlying drivers of urgent and emergency care reconfiguration in Ireland

BACKGROUND

There is an increasing tendency to reconfigure acute hospital care towards a more centralised and specialised model, particularly for complex care conditions. Although centralisation is presented as "evidence-based", the relevant studies are often challenged by groups which hold perspectives and values beyond those implicit in the literature. This study investigated stakeholder perspectives on the rationale for the reconfiguration of urgent and emergency care in Ireland. Specifically, it considered the hypothesis that individuals from different stakeholder groups would endorse different positions in relation to the motivation for, and goals of, reconfiguration.

METHODS

Documentary analysis of policy documents was used to identify official justifications for change. Semi-structured interviews with 175 purposively sampled stakeholders explored their perspectives on the rationale for reconfiguration.

RESULTS

While there was some within-group variation, internal and external stakeholders generally vocalised different lines of argument. Clinicians and management in the internal stakeholder group proposed arguments in favour of reconfiguration based on efficiency and safety claims. External stakeholders, including hospital campaigners and local political representatives expressed arguments that focused on access to care. A "voter" argument, focused on the role of local politicians in determining the outcome of reconfiguration planning, was mentioned by both internal and external stakeholders, often in a critical fashion.

CONCLUSION

Our study adds to an emerging literature on the interaction between a technocratic approach to health system planning advocated by clinicians and health service managers, and the experiential "non-expert" claims of the public and patients.

Precise spatio-temporal control of rapid optogenetic cell ablation with mem-KillerRed in Zebrafish

The ability to kill individual or groups of cells in vivo is important for studying cellular processes and their physiological function. Cell-specific genetically encoded photosensitizing proteins, such as KillerRed, permit spatiotemporal optogenetic ablation with low-power laser light. We report dramatically improved resolution and speed of cell targeting in the zebrafish kidney through the use of a selective plane illumination microscope (SPIM). Furthermore, through the novel incorporation of a Bessel beam into the SPIM imaging arm, we were able to improve on targeting speed and precision. The low diffraction of the Bessel beam coupled with the ability to tightly focus it through a high NA lens allowed precise, rapid targeting of subsets of cells at anatomical depth in live, developing zebrafish kidneys. We demonstrate that these specific targeting strategies significantly increase the speed of optoablation as well as fish survival.

Abstract P5-14-12: Long-term outcome of HER2-normal early stage breast cancer (ESBC) patients (Pts) treated with docetaxel-cyclophosphamide (TC) chemotherapy (CTx): Mature results of a single-institution experience

BACKGROUND

Anthracycline(A)-containing regimens (AReg) became an established standard (neo)adj CTx for ESBC following fairly consistent demonstration of a modest superiority over older anti-metabolite/alkylating CTx. However, substantial translational data and a recently presented pooled analysis [Blum, 2016] suggest that this superiority could be largely driven by greater benefits in specific ESBC subgroups, i.e. HER2-altered BrCa (due to co-amplification of topoisomerase 2 and HER2), and triple-negative BrCa (TNBC). A are cardiotoxic (including late onset of cardiomyopathic congestive heart failure) and potentially leukaemogenic. In late 2006, following the results of the first USONC randomized clinical trial that showed superior outcomes of the non-AReg TC (docetaxel/cyclo­phosphamide) over AC, we established a routine, uniform policy of TC for all Pts receiving (neo)adj CTx for HER2-normal ESBC. We report the mature follow up of this single-institution unselected experience.

METHODS

We performed a retrospective outcome analysis of all Pts who received at least 1 cycle of (neo)adj TC (docetaxel 75 mg/m2 + cyclophosphamide 600 mg/m2 IV every 3 weeks) at our Department for HER2-normal ESBC and with at least 5 years of follow up (FU). Pts were identified by systematic analysis of the dataset of the Oncology Pharmacy Unit. Information on tumour characteristics [e.g. axillary lymph nodes (N) metastases, hormonal receptors (HR) and HER2 status] and Pts FU were retrieved and collected into an ad hoc designed database. Pts with node-positive (N+) ESBC received TC×6 cycles, and Pts with high-risk node-negative (N−) [e.g. primary tumour (T) >2 cm, or HRneg, or T >3 cm] ESBC received TC×4 cycles. Pts received adjuvant hormone therapy and radiotherapy as per standard of care. From 2008 on, many lower risk HR+/N− Pts were not given CTx due to OncotypeDx availability.

RESULTS

Between September 2006 and December 2015, 810 female HER2-normal ESBC Pts were treated with (neo)adj TC. In the final outcome analysis we included 464 Pts treated before June 2011 thus having a minimum FU of 5 years. Pts characteristics are: median age 53 yrs (range 30-77), N− 246 (53%), N+ 218 (47%), hormone receptors positive (HR+) 391 (84%), TNBC 73 (16%). The database was locked as of June 1st 2016. Median FU from first cycle of TC is 7.5 yrs (range 5.3-10). 63 BrCa-specific relapse events (defined as time to local, regional or distant recurrence, invasive contralateral breast cancer, excluding non-breast second primaries) have been observed, accounting for an overall Relapse-Free Survival (RFS) rate of 86.4%. 42 deaths have occurred, 36 (86%) due to BrCa, accounting for an Overall Survival (OS) rate of 91%. RFS and OS rates for the different Pts subgroups are reported in Table 1

Table 1 - Outcome parameters RFS (%)OS (%)All Pts8691HR+/N-9396HR+/N+8190TN/N-9191TN/N+5858

CONCLUSIONS

These mature data with long FU suggest that the outcome for a large cohort of unselected Pts with HER2-normal HR+ ESBC (regardless of nodal status) and for TN/N− ESBrCa treated with nonAReg TC is excellent. However, N+TN ESBrCa in this setting remains a significant clinical challenge.

Citation Format: Losurdo A, Gullo G, Buckley C, Lowry C, Ballot J, Silva N, Hammond L, Crown J. Long-term outcome of HER2-normal early stage breast cancer (ESBC) patients (Pts) treated with docetaxel-cyclophosphamide (TC) chemotherapy (CTx): Mature results of a single-institution experience [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-14-12.

Characterization of ultrafiltration of undiluted and diluted stored urine

Urine ultrafiltration (UF) was studied in terms of flux, permeability, resistance and fouling. Two types of samples were used: stored urine representing the feedstock obtained from urine diversion dry toilets; and diluted stored urine representing the feedstock obtained from urinals. Three different filtration experiment sets were adopted in this study. For the first case, pressure was set in an ascending order, i.e. from 10 to 60 kPa during filtration of stored urine. For the second case, pressure was set in a descending order, i.e. from 60 to 10 kPa for the same feed stream. The third case involved filtration of diluted urine with pressure in ascending order, i.e. from 10 to 60 kPa. The results indicated that diluted urine had higher flux than undiluted urine with maximum values of 43 and 26 L·m^-2·h^-1 respectively. Cake formation was the dominating fouling mechanism during urine filtration with a contribution of about 90% to the total hydraulic resistance. The contribution of chemically irreversible fouling was low (-2%), unless operating from high to low pressures. Indeed, irreversible fouling appeared to be greater during the experiments starting at higher pressure. Although undiluted urine had a higher fouling potential compared to diluted urine, the specific cake resistance was higher for diluted urine, probably due to a denser cake caused by lower particle sizes in that sample. The permeate obtained after urine filtration had much lower suspended solids content compared to the feedstock, with rejections up to 99%. The concentration of the ionic species remained unchanged, and 75% of the organic compounds and dissolved solids remained in the permeate. Urine UF could then be used as pre-treatment to remove suspended solids.

Controlling embedment and surface chemistry of nanoclusters in metal–organic frameworks

A combined theoretical and experimental approach demonstrates that nanocluster embedment into the pores of metal–organic frameworks (MOF) may be influenced by the chemical functionalisation of the MOF.