Development and application of consensus in silico models for advancing high-throughput toxicological predictions

Computational toxicology models have been successfully implemented to prioritize and screen chemicals. There are numerous in silico (quantitative) structure-activity relationship ([Q]SAR) models for the prediction of a range of human-relevant toxicological endpoints, but for a given endpoint and chemical, not all predictions are identical due to differences in their training sets, algorithms, and methodology. This poses an issue for high-throughput screening of a large chemical inventory as it necessitates several models to cover diverse chemistries but will then generate data conflicts. To address this challenge, we developed a consensus modeling strategy to combine predictions obtained from different existing in silico (Q)SAR models into a single predictive value while also expanding chemical space coverage. This study developed consensus models for nine toxicological endpoints relating to estrogen receptor (ER) and androgen receptor (AR) interactions (i.e., binding, agonism, and antagonism) and genotoxicity (i.e., bacterial mutation, in vitro chromosomal aberration, and in vivo micronucleus). Consensus models were created by combining different (Q)SAR models using various weighting schemes. As a multi-objective optimization problem, there is no single best consensus model, and therefore, Pareto fronts were determined for each endpoint to identify the consensus models that optimize the multiple-criterion decisions simultaneously. Accordingly, this work presents sets of solutions for each endpoint that contain the optimal combination, regardless of the trade-off, with the results demonstrating that the consensus models improved both the predictive power and chemical space coverage. These solutions were further analyzed to find trends between the best consensus models and their components. Here, we demonstrate the development of a flexible and adaptable approach for in silico consensus modeling and its application across nine toxicological endpoints related to ER activity, AR activity, and genotoxicity. These consensus models are developed to be integrated into a larger multi-tier NAM-based framework to prioritize chemicals for further investigation and support the transition to a non-animal approach to risk assessment in Canada.

Anal Canal Adenocarcinomas: Prognostic Factors and Outcomes at a Single Institution

PURPOSE/OBJECTIVE(S)

Adenocarcinomas of the anal canal (AAC) represent a rarity among cancers of the digestive tract. Data guiding management is limited to retrospective studies and optimal treatment paradigms of AAC are still evolving. Here, we aim to investigate their prognostic factors and outcomes.

MATERIALS/METHODS

We reviewed anorectal adenocarcinoma patients who underwent curative-intent neo/adjuvant therapy +/- surgery at a single institution from 2015-2019. AAC were defined as tumor epicenters ≤ 2 cm from the dentate line. Our primary outcome was 5-year overall survival (OS). We also analyzed 5-year local recurrence, distant metastasis, and disease-free survival (DFS), defined as the interval after treatment completion to the first occurrence of local, regional, distant recurrence, or death. All tumors were staged according to the Rectal Cancer paradigm per AJCC 7th Staging. Kaplan-Meier and Cox-Proportional Hazards Model were used for survival analyses.

RESULTS

In our cohort, 57 patients met inclusion criteria. Median follow-up time was 54 months. The median age was 64 years; 35% of the cohort was female. The majority of tumors were adenocarcinomas (77%), with a minority of mucinous (12%) and signet ring cell (11%) histologies. The median tumor size was 4 cm, located 1 cm from the anal verge. Most tumors (63%) were grade 2, 77% had T3 disease, and 53% had clinical nodal involvement. Most patients completed neoadjuvant chemoradiation, total mesorectal excision, and adjuvant chemotherapy (54%). Fifty-four percent underwent abdominopelvic resection. Of those who received neoadjuvant therapy, 11% achieved a pathologic complete response. Seventy percent of patients completed chemotherapy, either in the neoadjuvant or adjuvant setting. At 5 years, local recurrence was 9%, regional pelvic recurrence was 12%, inguinal nodal recurrence was 2%, and distant recurrence was 25%. Five-year DFS was 63% and 5-year OS was 70%. Multivariate analysis demonstrated age, female gender, CEA, grade 3 disease, mucinous histology, and nodal involvement to be prognostic of lower OS. Receipt of neo/adjuvant chemotherapy was found to be prognostic of higher OS (HR 0.13, p<0.05).

CONCLUSION

In this cohort, the majority of whom received surgical management, we show numerically similar or higher overall survival in comparison with prior studies. This study is limited by its retrospective nature and sample sizes of an exceedingly rare entity. Receipt of neo/adjuvant chemotherapy appears to have an impact on survival. Further investigation is needed to explore the role of total neoadjuvant therapy in improving outcomes in this patient population.

A randomized controlled trial evaluating a theory driven, complex intervention centered on task sharing and mobile health to improve selfcare and outcomes in heart failure - The PANACEA-HF RCT: Design and rationale

Background

We developed a three-pronged complex intervention to improve selfcare and deliver whole person care for patients with heart failure, underpinned by the 'extant cycle' theory - a theory based on our formative work.

Methods

This is a 3 centre, 2-arm, 1:1, open, adaptive stratified, randomized controlled trial. We included patients aged ≥ 18 years with heart failure, taking any of the key guideline directed medical treatments, with a history of or currently on a high ceiling diuretic. We excluded end stage renal disease, clinically diagnosed severe mental illness or cognitive dysfunction and having no caregivers. Interventions included, (i) trained hospital based lay health worker mediated assessment of patients' current selfcare behaviour, documenting barriers and facilitators and implementing a plan to 'transition' the patient toward optimal selfcare. (ii) m-health mediated remote monitoring and (iii) dose optimization through a 'physician supervisor'.

Results

We recruited 301 patients between Jan 2021 and Jan 2022. Mean age was 59.8 (±11.7) years, with 195 (64.8 %) from rural or semi-urban areas and 67.1 % having intermediate to low health literacy. 190 (63.1 %) had an underlying ischemic cardiomyopathy. In the intervention arm, 142 (94.1 %) had a Selfcare in Heart Failure Index (SCHFI) score of ≤70, with significant barriers being 'lack of knowledge' 105 (34.5 %) and 'behavioural passivity' 23 (7.5 %).

Conclusion

This is the first South Asian trial evaluating a complex intervention underpinned by behaviour change theory for whole person heart failure care. These learnings can be applied to heart failure patient care in other resource constrained health systems.

A Quasi Universal Matalon-Packter Law for a Periodically Precipitating System of Iron(II) Hydroxide Involving Volumes and Concentrations of the Invading Electrolyte

The Matalon-Packter (MP) empirical law of periodically precipitating (Liesegang phenomenon) systems under non-equilibrium conditions describes the dependence of the periodicity (spacing coefficient) on the initial concentration of the outer electrolyte. We aim to present the MP law in a more generalized form using a realistic approach wherein mass transfer in the gel column plays a role instead of the initial concentrations. This work is an attempt to make such progress. The Liesegang bands of Fe(OH)2 were studied by varying the reservoir concentrations (c) and volumes (V) of the outer electrolyte (NH4OH). The spacing coefficient was found to be a function of the volume and concentration of the outer electrolyte. It was observed that the amount of chemical substance (cV) and the average molar diffusion flux (Fdiff) of the ions of the outer electrolyte could be a unifying quantity for expressing the MP law instead of the initial electrolyte concentration. We demonstrated that a single model is possible for a system, irrespective of the V value. Three different volumes were employed, and the calculations were performed under small, intermediate, and larger reservoir volume regimes. Interestingly, a single model was observed for the diffusion coefficients for all of the Fdiff values.

High Throughput Read-Across for Screening a Large Inventory of Related Structures by Balancing Artificial Intelligence/Machine Learning and Human Knowledge

Read-across is an in silico method applied in chemical risk assessment for data-poor chemicals. The read-across outcomes for repeated-dose toxicity end points include the no-observed-adverse-effect level (NOAEL) and estimated uncertainty for a particular category of effects. We have previously developed a new paradigm for estimating NOAELs based on chemoinformatics analysis and experimental study qualities from selected analogues, not relying on quantitative structure-activity relationships (QSARs) or rule-based SAR systems, which are not well-suited to end points for which the underpinning data are weakly grounded in specific chemical-biological interactions. The central hypothesis of this approach is that similar compounds have similar toxicity profiles and, hence, similar NOAEL values. Analogue quality (AQ) quantifies the suitability of an analogue candidate for reading across to the target by considering similarity from structure, physicochemical, ADME (absorption, distribution, metabolism, excretion), and biological perspectives. Biological similarity is based on experimental data; assay vectors derived from aggregations of ToxCast/Tox21 data are used to derive machine learning (ML) hybrid rules that serve as biological fingerprints to capture target-analogue similarity relevant to specific effects of interest, for example, hormone receptors (ER/AR/THR). Once one or more analogues have been qualified for read-across, a decision theory approach is used to estimate confidence bounds for the NOAEL of the target. The confidence interval is dramatically narrowed when analogues are constrained to biologically related profiles. Although this read-across process works well for a single target with several analogues, it can become unmanageable when, for example, screening multiple targets (e.g., virtual screening library) or handling a parent compound having numerous metabolites. To this end, we have established a digitalized framework to enable the assessment of a large number of substances, while still allowing for human decisions for filtering and prioritization. This workflow was developed and validated through a use case of a large set of bisphenols and their metabolites.

Manipulation of distal radius fractures: a comparison of Bier's block vs haematoma block

INTRODUCTION

Displaced distal radius fractures often require manipulation under anaesthesia. Many anaesthetic techniques are described, with the two most commonly used being Bier's block (BB) and haematoma block (HB). Despite national guidance preferring a BB, an HB is often performed instead. This study aims to compare the analgesic properties of a BB with those of an HB when manipulating distal radius fractures.

METHODS

This is an observational cohort study comparing the management of displaced distal radius fractures requiring reduction across two National Health Service trusts. Patients aged over 18 with isolated, displaced distal radius fractures were recruited. Patient demographics, AO fracture classification and grade of clinician performing the procedure were recorded. A numeric rating scale (NRS) pain score was obtained for each patient after manipulation. The quality of reduction was judged against standardised anatomical parameters.

RESULTS

Some 200 patients were recruited (100 HB, 100 BB). There were no differences in age (BB: median 66.5 years, interquartile range [IQR] 55-74; HB: median 67 years, IQR 55-74; p = 0.79) or fracture characteristics (p = 0.29) between cohorts. Patients undergoing BB had significantly lower pain scores with a lower IQR than those undergoing HB (p < 0.005). Patients undergoing BB manipulation were more likely to have the fracture reduced and normal anatomy restored (p < 0.005). BBs were performed mainly by Foundation Year 2 junior doctors, whereas HB manipulations were performed by a range of clinicians from emergency nurse practitioners to consultants.

CONCLUSIONS

BB provides better analgesia than an HB. This can be performed successfully and reliably by Senior House Officer-level junior doctors.

1028 Systematic Review of Outcomes of Applications of Prineo-Dermabond

Aim

The aims of this study are to assess published data regarding infection rates, delayed wound healing, cosmetic appearance and application time compared to conventional wound closure techniques across multiple surgical procedures.

Method

A literature search was conducted according to PRISMA guideline using PubMed, SCOPUS and Science Direct. The primary outcome was the incidence of wound infection after Prineo Dermabond compared to controls. Secondary outcome measures included allergic reactions and time for application. Literature search identified 52 studies, of which 19 were eligible for qualitative synthesis and 12 for meta-analysis.

Results

Studies included reflected a broad range of applications of Dermeo-Prineo to wound closure in Abdominoplasty, Mammoplasty and Arthroplasty.

Overall, all studies reporting on time of application found a positive indicator of Prineo Dermabond reducing time for wound closure.

Meta-analysis identified a statistically significant reduction in rates of the 6 studies that described wound infection (Prineo 1.51%, Control N=2.13%, OR 0.65 (0.46–0.91); P=0.01) and in the 5 studies reporting delayed wound healing (Prineo 0.99%, Control N=1.79%, OR 0.42 (0.18–0.98); P=0.05) in the use of Prineo Dermabond versus controls.

Three studies reported outcomes of scar cosmesis or long-term maturation. All attested to better cosmetic results in comparison to sutures.

Two studies discussed cost-effectiveness of Dermabond with a hypothetical model concluded that Skin Closure System of Prineo Dermabond could achieve savings of $50–76 per patient, whilst a retrospective model found no statistically significant difference in Total Hospital costs or Operating room time.

Conclusions

Prineo Dermabond provides an alternative method of wound closure in reported studies.

Identification of a novel mutation in thyroxine-binding globulin (TBG) gene associated with TBG-deficiency and its effect on the thyroid function

PURPOSE

This study presents a case of familial transmission of thyroxine-binding globulin (TBG) deficiency. The SERPINA7-gene which codes for TBG is located on the X-chromosome (Xq21-22). More than 45 mutations have been reported to cause TBG- deficiency from various countries, but none from India so far. Genetic analysis of SERPINA7 gene was carried out to determine the cause of low TBG levels in one family.

METHODS

DNA samples of the propositus and the family members were subjected to Polymerase Chain Reaction (PCR) followed by direct sequencing. Allele-specific PCR and Next-gen sequencing (NGS) were employed to confirm the site of the mutation. Thyroid function tests were estimated by Radioimmunoassay (RIA) and Immunoradiometric assay (IRMA) kits. X-chromosomal inactivation status was analyzed in the female members harboring the mutation.

RESULTS

A mutational screening in this family revealed a novel frame-shift mutation S353Q, 354fs3X in the exon 4 of the SERPINA7 gene which will be referred to as TBG-complete deficiency-India (TBG-CD-Ind). One out of four female family members harboring the mutation showed selective X-chromosomal inactivation. The affected family members were clinically euthyroid initially, showed changes in the thyroid function when tested after a long time span. However, the changes in the thyroid function in the affected family members had an autoimmune etiology.

CONCLUSION

This study presents the first report of TBG-CD from India wherein a novel frameshift mutation referred to as TBG-CD-Ind (S353Q, 354fs3X) in the SERPINA7 gene was detected. No apparent association was identified between thyroid function and the TBG-mutation in the affected subjects. A detailed biochemical and genomic testing to determine the exact cause of discordant TFT in the patients would certainly aid in the unequivocal diagnosis of the thyroid function and for the precise individualized treatment.

Canadian Regulatory Perspective on Next Generation Risk Assessments for Pest Control Products and Industrial Chemicals

In 2012, the Council of Canadian Academies published the expert panel on integrated testing of pesticide’s report titled: Integrating emerging technologies into chemical safety assessment. This report was prepared for the Government of Canada in response to a request from the Minister of Health and on behalf of the Pest Management Regulatory Agency. It examined the scientific status of the use of integrated testing strategies for the regulatory health risk assessment of pesticides while noting the data-rich/poor dichotomy that exists when comparing pesticide formulations to most industrial chemicals. It also noted that the adoption of integrated approaches to testing and assessment (IATA) strategies may refine and streamline testing of chemicals, as well as improve results in the future. Moreover, the experts expected to see an increase in the use of integrated testing strategies over the next decade, resulting in improved evidence-based decision-making. Subsequent to this report, there has been great advancements in IATA strategies, which includes the incorporation of adverse outcome pathways (AOPs) and new approach methodologies (NAMs). This perspective provides the first Canadian regulatory update on how Health Canada is also advancing the incorporation of alternative, non-animal strategies, using a weight of evidence approach, for the evaluation of pest control products and industrial chemicals. It will include specific initiatives and describe how this work is leading to the creation of next generation risk assessments. It also reflects Health Canada’s commitment towards implementing the 3Rs of animal testing: reduce, refine and replace the need for animal studies, whenever possible.

An assessment of a multipoint dosing approach for exothermic nitration in CSTRs in series

Multipoint dosing strategy for scale-up of exothermic aromatic nitration.

In Silico Models for Developmental Toxicity

Modeling developmental toxicity has been a challenge for (Q)SAR model developers due to the complexity of the endpoint. Recently, some new in silico methods have been developed introducing the possibility to evaluate the integration of existing methods by taking advantage of various modeling perspectives. It is important that the model user is aware of the underlying basis of the different models in general, as well as the considerations and assumptions relative to the specific predictions that are obtained from these different models for the same chemical. The evaluation on the predictions needs to be done on a case-by-case basis, checking the analogues (possibly using structural, physicochemical, and toxicological information); for this purpose, the assessment of the applicability domain of the models provides further confidence in the model prediction. In this chapter, we present some examples illustrating an approach to combine human-based rules and statistical methods to support the prediction of developmental toxicity; we also discuss assumptions and uncertainties of the methodology.

Insights into complex nanopillar-bacteria interactions: Roles of nanotopography and bacterial surface proteins

Nanopillared surfaces have emerged as a promising strategy to combat bacterial infections on medical devices. However, the mechanisms that underpin nanopillar-induced rupture of the bacterial cell membrane remain speculative. In this study, we have tested three medically relevant poly(ethylene terephthalate) (PET) nanopillared-surfaces with well-defined nanotopographies against both Gram-negative and Gram-positive bacteria. Focused ion beam scanning electron microscopy (FIB-SEM) and contact mechanics analysis were utilised to understand the nanobiophysical response of the bacterial cell envelope to a single nanopillar. Given their importance to bacterial adhesion, the contribution of bacterial surface proteins to nanotopography-mediated cell envelope damage was also investigated. We found that, whilst cell envelope deformation was affected by the nanopillar tip diameter, the nanopillar density affected bacterial metabolic activities. Moreover, three different types of bacterial cell envelope deformation were observed upon contact of bacteria with the nanopillared surfaces. These were attributed to bacterial responses to cell wall stresses resulting from the high intrinsic pressure caused by the engagement of nanopillars by bacterial surface proteins. Such influences of bacterial surface proteins on the antibacterial action of nanopillars have not been previously reported. Our findings will be valuable to the improved design and fabrication of effective antibacterial surfaces.

Cement beads and cement spacers: indications, techniques, and clinical results

Objectives

To report our experience on the use of antibiotic coated nails (ACN) and cement beads for the management of bone infections.

Materials and methods

Infected nonunion (INU) cases were classified as: Type I (mild infection with no gap), Type II (moderate with good alignment, severe infection, gap <3 cm, no deformity), Type III (severe infection with gap ≥3 cm, deformity and limb shortening). Treatment involved either the insertion of ACN and cast (Type I), insertion of ACN, beads and external fixator (Type II), or Ilizarov methodology (Type III). A subset of 28 open fractures were admitted with severe contamination or delayed presentation with established infection and treated with debridement, ACN insertion, and antibiotic beads placed in soft tissue dead space areas.

Results

Results of 133 cases were classified excellent, good, and poor. Type I INU reported 40 excellent and 22 good results. Type II INU reported 28 (39%) excellent, 30 (43%) good, and 13 (18%) poor results. Poor results were due to uncontrolled infection and knee stiffness. Three patients required knee fusion and 1 required amputation. Fracture union was reported in 68 cases. Four of the 28 Gustilo grade III open fractures treated with ACN developed infected nonunion and had poor function caused by stiff knees.

Conclusions

An antibiotic impregnated cement nail (ACN) fills the dead space and elutes high concentrations of antibiotics providing some mechanical stability. We recommend the adjunct use of an ACN for the management of INU cases and for use in select cases of Gustilo grade III open fractures.

Annular pancreas causing pyloric stenosis in a 66-year-old patient treated with gastrojejunostomy: a case report

Annular pancreas is defined by a ring of pancreatic tissue encircling the descending portion of the duodenum. It is exceptionally rare in adults and commonly diagnosed during the investigation of symptoms arising due to its complications. Treatment usually involves the surgical correction with a duodenoduodenostomy, gastrojejunostomy or duodenojejunostomy. We discuss the case of a 66-year-old male patient who presented with symptoms of gastric outlet obstruction and was found to have an annular pancreas encircling the pylorus and the first and second portions of the duodenum and was treated by performing a gastrojejunostomy. Upper gastrointestinal series, computerized tomography (CT) scans, and magnetic resonance cholangeopancreatographys can all be used for preoperative diagnosis; however, endoscopic retrograde cholangiopancreatography (ERCP) is the diagnostic modality of choice. Nonetheless, many patients may only be diagnosed intraoperatively, especially those who cannot undergo an ERCP due to stenosis proximal to the duodenum or patients in whom the annulus may not be visible on CT scan.

4,5,6,7-Tetrabromo-2,3-dihydro-1,1,3-trimethyl-3-(2,3,4,5-tetrabromophenyl)-1H-indene (OBTMPI): Levels in humans and in silico toxicological profiles

Limited human exposure and toxicity data are currently available for 4,5,6,7-Tetrabromo-2,3-dihydro-1,1,3-trimethyl-3-(2,3,4,5-tetrabromophenyl)-1H-indene (OBTMPI), a flame retardant often used for high temperature application of various polymer materials. Levels of OBTMPI in a cohort population that includes children and their co-residing parents (n = 217) in Canada were determined. Detection frequency of OBTMPI in the samples was 22.6%. OBTMPI levels were in general at sub-to low ng/g lipid weight level with a 95th percentile at 15.6 ng/g lipid weight. Compared to an earlier study conducted in 2008-2009 in the same region, results from this study show an increase in both detection frequency and concentration of OBTMPI. In silico toxicity predictions using Multicase CaseUltra and Leadscope Model Applier suggested that OBTMPI, and its possible metabolites in humans, while unlikely to be carcinogenic or mutagenic, exhibit some estrogen antagonist, androgen antagonist and estrogen binding capability reflective of possible endocrine disrupting properties.

Do Similar Structures Have Similar No Observed Adverse Effect Level (NOAEL) Values? Exploring Chemoinformatics Approaches for Estimating NOAEL Bounds and Uncertainties

Determination of the no observed adverse effect level (NOAEL) of a substance is an important step in safety and regulatory assessments. Application of conventional in silico strategies, for example, quantitative structure-activity relationship (QSAR) models, to predict NOAEL values is inherently problematic. Whereas QSAR models for well-defined toxicity endpoints such as Ames mutagenicity or skin sensitization can be developed from mechanistic knowledge of molecular initiating events and adverse outcome pathways, QSAR is not appropriate for predicting a NOAEL value, a concentration at which "no effect" is observed. This paper presents a chemoinformatics approach and explores how it can be further refined through the incorporation of toxicity endpoint-specific information to estimate confidence bounds for the NOAEL of a target substance, given experimentally determined NOAEL values for one or more suitable analogues. With a sufficiently large NOAEL database, we analyze how a difference in NOAEL values for pairs of structures depends on their pairwise similarity, where similarity takes both structural features and physicochemical properties into account. The width of the estimate NOAEL confidence interval is proportional to the uncertainty. Using the new threshold of toxicological concern (TTC) database enriched with antimicrobials, examples are presented to illustrate how uncertainty decreases with increasing analogue quality and also how NOAEL bounds estimation can be significantly improved by filtering the full database to include only substances that are in structure categories relevant to the target and analogue.

Point-of-care lung ultrasound in intensive care during the COVID-19 pandemic

Coronavirus disease 2019 has spread to every inhabited continent in the world. So far, plain radiography and computed tomography have been the mainstay of imaging methods used. The present analytical paper on the role of point-of-care lung ultrasound in this pandemic examines its diagnostic accuracy, clinical utility, and physical practicality in the intensive care unit.

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POCUS has a high sensitivity for pulmonary manifestations of COVID-19.

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POCUS minimises nosocomial spread.

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POCUS can prognosticate and assess response to therapy.

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Healthcare providers with skills in POCUS are encouraged to help provide this service.

Botulinum toxin in the management of temporomandibular disorders: a systematic review

The aim of this review was to critically investigate and assess the evidence relating to the use and efficacy of botulinum toxin (BTX) in the management of temporomandibular joint disorders (TMD) and masticatory myofascial pain. A comprehensive search was conducted of PubMed, Scopus, Embase, and Cochrane CENTRAL, to find relevant studies from the last 30 years up to the end of July 2018. Seven were identified. Three showed a significant reduction in pain between the BTX and placebo groups and one showed a clinical, but not a significant, difference. In one that compared BTX with another novel treatment, myofascial pain reduced equally in both groups, and in the remaining two there was no significant difference in pain reduction between the BTX and control groups. Of the four studies that assessed mouth opening, two reported that BTX had resulted in a slight improvement; one reported no improvement, and the other a worsening of the condition. A meta-analysis was not possible because of the considerable variation in the studies' designs, the heterogeneity between the groups, and the different assessment tools used. Despite showing benefits, consensus on the therapeutic benefit of BTX in the management of myofascial TMD is lacking. Further randomised controlled trials with larger sample sizes, minimal bias, and longer follow-up periods are now needed.

P4396Patients explanations of self-care in chronic heart failure: a grounded theory analysis of qualitative data from PANACEA-HF Phase 1

Background

Sub-optimal self-care and non-adherence to treatments are important predictors of poor clinical outcomes in patients with heart failure. Task-sharing and technology have each contributed modest improvements, but the combined effect on outcomes is unknown. We aim to develop a complex intervention package to improve self-care predicated on task sharing and smartphone based remote monitoring among heart failure patients.

Purpose

As a formative step, we conducted a qualitative study among heart failure patients and their caregivers to explore self-care and to inform the development of a contextualized intervention package.

Methods

We conducted in-depth interviews among 22 patients admitted to in-patient wards with a clinical diagnosis of chronic heart failure (diagnosis made at least 1 month prior to index hospitalization) and 18 caregivers (n=40), sampled from 4 states in southern India. Patients were purposively sampled based on sex, socioeconomic status, health literacy and past one month's history of adherence to heart failure medications. The middle range theory of self-care informed the drafting of the interview guide. We recorded and transcribed interviews translated from 5 regional languages. We inductively coded the data from a social constructionist viewpoint, created categories, prepared memos, compared extreme cases, identified key emergent themes and their inter-relationships.

Results

Patients' mean age was 60.5 (±13.4), with representation from socioeconomic strata, urban and rural areas. Patients had a high pill burden [median 10; IQR (6, 31)] and 8 (44%) reported irregular adherence to prescribed medications in the last month. Key categories associated with sub-optimal self-care included “Passivity”, “Entrenched Belief systems”, “Negative Emotions/Affect”, “Ageing causes disease”, and “inability to control situations” across all socioeconomic strata. These themes appear to impair self-actualization that negatively impacts self efficacy/confidence and in turn self-care reciprocally (Refer Figure). Key facilitators of self-care were: Intrinsic patient distinctive facilitators (situational awareness, resilience) and extraneous facilitators (insurance/financial protection, positive caregiver relationships and ease of healthcare access). Patients and caregivers generally expressed their readiness to use mobile technology for remote monitoring and to be counseled by trained lay workers to address beliefs and be trained on self-care.

Framework explaining self-care in HF

Conclusions

Findings from this formative study show opportunities for providers and community-based care workers to address task-sharing of beliefs by educating patients on self-care, including through the use of technology-based solutions. These findings regarding a self-care framework identify opportunities to improve self-care among heart failure patients using task-sharing and technology to support the patient-caregiver-provider triad.

Acknowledgement/Funding

India Alliance - Wellcome Trust and Department of Biotechnology

Study of Rheology and Plug Assist Thermoforming of Linear and Branched PP Homopolymer and Impact Copolymer

Polypropylene (PP) is one of the fastest growing thermoplastic polymers in the world, second only to polyethylene. This is primarily due to its excellent balance of physical and chemical properties at a lower cost. PP however possesses low melt strength on account of its linear structure and hence is not easily amenable to processing techniques that involve free surface stretching deformations like thermoforming, blow molding and extrusion film casting. One way to enhance the melt strength of PP is to incorporate long chain branches in its molecular architecture. The present study focuses on the impact of rheology of linear and branched PP on their thermoforming characteristics. Two grades each of linear and long chain branched (LCB) PP homopolymer and impact copolymer (ICP) were used. It was observed that the LCB-PP homopolymer and LCB-ICP showed higher flow activation energy, reduced value of loss tangent and nearly equal frequency dependence of storage and loss moduli in shear rheology. Also, a strong strain hardening behavior was displayed in extensional rheology by the LCB grades. Plug assist thermoforming experiments were carried out to assess the effect of long chain branching on surface strain and thickness distribution for axisymmetric cups of two draw ratios. Biaxial surface strain maps of the formed cups were quantified using Grid Strain Analysis (GSA). Thermoformed cups made from LCB-PP homopolymer and LCB-impact copolymer showed lower surface strain and overall higher thickness as compared to cups made from their linear counterparts, which is in accordance with what might be expected from their rheology.

Abstract P6-21-12: Local transdermal therapy (LTT): Drug permeation and distribution of telapristone acetate (TPA) in a pre-surgical window study of women undergoing mastectomy

Background: Low uptake and poor adherence to oral drugs for breast cancer prevention and ductal carcinoma in situ has led to an interest in local routes of delivery with the intent of decreasing systemic exposure and reducing toxicity. LTT has emerged as a possible alternative; previous studies have shown selectively higher concentrations in the breast than in the serum with this delivery route. A question related to LTT is whether or not the drug will permeate and distribute throughout the breast, as is expected with oral delivery.

Methods: We conducted a double-blind study of oral versus LTT delivery of the selective progesterone receptor modulator, telapristone acetate (TPA), in a presurgical window setting, enrolling 82 women planning therapeutic or prophylactic mastectomy. We randomized 67 women 1:1, to oral TPA 12 mg daily, or gel TPA applied to both breasts daily (12 mg/breast), for 4 weeks ±1 week. Mastectomy specimens were sampled at 5 non-tumor locations as well as the tumor and lymph node when available. Samples were split in two: drug concentration (conc.) assay using LC-MS/MS and histological evaluation of tissue composition (fat, fibrous stroma, epithelium). The primary endpoint was mean drug conc. across all breast locations (anticipating that the gel would deliver a mean concentration that was &gt;50% of the mean in the oral group). A secondary endpoint was the drug distribution pattern across the breast, expecting that the distribution would be similar. The tumor sample was saved for biomarker assays related to TPA action; these are ongoing, for a pre-planned pooled analysis of data with NCT01800422 (reported in SABCS abstract 851863).

Results: Of 63 evaluable women (33 oral and 30 gel group), 27 had unilateral and 36 had bilateral mastectomy. The mean drug conc. in the oral group was 166.3 ng/G (SE 11.7), and in the gel group was 10.6 ng/G (SE 10.8), (p&lt;.0001). The conc. was variable across the 7 locations tested in both groups. High concentrations were found in the superficial and deep central locations, retroareolar and lateral locations ranked in the middle, and the medial location was discrepant, being high in the oral and low in the gel group. The variation in drug concentration across all locations was not significantly different between groups (Kolmogorov-Smirnov p=0.99). Among women with bilateral mastectomy, drug concentrations were similar between breasts in both oral and gel groups. In the gel group, despite low TPA concentrations, there was evidence of drug metabolism. The major metabolite, CDB 4453 was detectable in 192/193 samples with detectable parent drug. Analysis of drug concentration adjusted for tissue composition is ongoing.

Conclusions: The gel formulation of TPA did not permeate the skin well. However, the drug delivered to the breast was distributed throughout the breast, similar to the oral delivery route, with the highest concentration in the deep central location. These drug distribution data are novel; drug distribution at multiple locations throughout the breast has not previously been shown. Further work is needed to understand breast distribution with formulations known to have good dermal permeation.

Citation Format: Lee O, Pilewskie M, Xu Y, Benante K, Blanco L, Helenowski I, Tull MB, Muzzio M, Jovanovic B, Karlan S, Hansen N, Bethke K, Kulkarni S, Perloff M, Dimond EP, Heckman-Stoddard BM, Khan SA. Local transdermal therapy (LTT): Drug permeation and distribution of telapristone acetate (TPA) in a pre-surgical window study of women undergoing mastectomy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-21-12.

Abstract P5-04-04: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Das GM, Kulkarni S, Oturkar C, Edge SB, Wilton JH, Wang J, Swetzig WM, Adjei AA, Bies R, Hutson AD, Morrison CD, Kaipparettu BA, Groman A, Kumar S, Capuccino H. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-04-04.

Abstract P1-13-08: A prospective non-randomized clinical trial of adjuvant carboplatin chemotherapy in triple negative breast cancer

Background: The addition of carboplatin in the neoadjuvant setting has demonstrated improved outcomes in patients with triple negative breast cancer (TNBC). Carboplatin in the adjuvant setting has not been demonstrated to be an accepted regimen to date. This trial addresses this issue.

Methods: The primary objectives of this study were to assess the toxicity of an adjuvant carboplatin-containing regimen for early stage TNBC patients, and to correlate outcomes with molecular markers including Spy-1. Secondary objectives included determination of progression free (PFS) and overall survival (OS), and comparing these to our institutional historical controls. Patients received the backbone of a dose dense anthracycline, taxane, cyclophosphamide (DD ACT), with the addition of carboplatin.

Results: Ninety patients with stage I to III patients with triple negative breast cancer were accrued to this trial between Jan 2011 and June 2017. We discovered that DD ACT with carboplatin with an AUC of 5 given on the second and last paclitaxel was well tolerated. Chemotherapy delays were minimized when the parameters for administration of the carboplatin was to allow chemotherapy to proceed if the platelet count was &gt;/= 70,000 x10^9/L and dose adjustment of paclitaxel was allowed based on neuropathy. There were no grade 4 adverse events. 4% of patients had grade 3 peripheral neuropathy (PN), 28% had grade 2 PN and 45% had grade 1 PN. Results of molecular profiles will be reported. Univariate analysis are reported, and were found to be very promising. Using log-rank statistic, a trend to improvement in overall survival was found when compared to historical controls (p=0.089). Median follow-up is 24 months. Longer follow-up is necessary to determine PFS and overall survival benefit.

Conclusion: If considering an adjuvant regimen for triple negative breast cancer patients DDAC/TC with the carboplatin administered with an AUC of 5 on the second and fourth taxol of DDACT is a well-tolerated regimen.

Univariate Analysis Comparing Carboplatin vs Historical Controls that did not receive CarboplatinVariableHistorical (no carbo)Carbo containing chemop overall n = 179n = 82 Age56.3 (13.1)49.8 (11.0)&lt; 0.001Stage0.188Stage I47 (26.3%)15 (18.3%) Stage II88 (49.2%)50 (61.0%) Stage III44 (24.6%)17 (20.7%) Grade0.011Grade 18 (4.5%)0 (0.0%) Grade 233 (18.4%)7 (8.8%) Grade 3138 (77.1%)73 (91.2%) Remission Status0.009In Remission126 (70.4%)70 (86.4%) Relapsed53 (29.6%)11 (13.6%) Survival&lt; 0.001Alive121 (67.6%)73 (90.1%) Deceased58 (32.4%)8 (9.9%) 

Citation Format: Hamm C, Kulkarni S, Gupta R, Mathews J, Amin K, Hussein A, Porter L. A prospective non-randomized clinical trial of adjuvant carboplatin chemotherapy in triple negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-13-08.

Quantitation of class IA PI3Ks in mice reveals p110-free-p85s and isoform-selective subunit associations and recruitment to receptors

Class IA PI3Ks have many roles in health and disease. The rules that govern intersubunit and receptor associations, however, remain unclear. We engineered mouse lines in which individual endogenous class IA PI3K subunits were C-terminally tagged with 17aa that could be biotinylated in vivo. Using these tools we quantified PI3K subunits in streptavidin or PDGFR pull-downs and cell lysates. This revealed that p85α and β bound equivalently to p110α or p110β but p85α bound preferentially to p110δ. p85s were found in molar-excess over p110s in a number of contexts including MEFs (p85β, 20%) and liver (p85α, 30%). In serum-starved MEFs, p110-free-p85s were preferentially, compared with heterodimeric p85s, bound to PDGFRs, consistent with in vitro assays that demonstrated they bound PDGFR-based tyrosine-phosphorylated peptides with higher affinity and co-operativity; suggesting they may act to tune a PI3K activation threshold. p110α-heterodimers were recruited 5-6× more efficiently than p110β-heterodimers to activated PDGFRs in MEFs or to PDGFR-based tyrosine-phosphorylated peptides in MEF-lysates. This suggests that PI3Kα has a higher affinity for relevant tyrosine-phosphorylated motifs than PI3Kβ. Nevertheless, PI3Kβ contributes substantially to acute PDGF-stimulation of PIP3 and PKB in MEFs because it is synergistically, and possibly sequentially, activated by receptor-recruitment and small GTPases (Rac/CDC42) via its RBD, whereas parallel activation of PI3Kα is independent of its RBD. These results begin to provide molecular clarity to the rules of engagement between class IA PI3K subunits in vivo and past work describing "excess p85," p85α as a tumor suppressor, and differential receptor activation of PI3Kα and PI3Kβ.

Toxicology study for magnetic injection of prednisolone into the rat cochlea

This paper investigates the safety of a novel 'magnetic injection' method of delivering therapy to the cochlea, in a rodent model. In this method of administration, a magnetic field is employed to actively transport drug-eluting superparamagnetic iron-oxide core nanoparticles into the cochlea, where they then release their drug payload (we delivered the steroid prednisolone). Our study design and selection of control groups was based on published regulatory guidance for safety studies that involve local drug delivery. We tested for both single and multiple delivery doses to the cochlea, and found that magnetic delivery did not harm hearing. There was no statistical difference in hearing between magnetically treated ears versus ears that received intra-tympanic steroid (a mimic of a standard-of-care for sudden sensorineural hearing loss), both 2 and 30 days after treatment. Since our treatment is local to the ear, the levels of steroid and iron circulating systemically after our treatment were low, below mass-spectrometry detection limits for the steroid and no different from normal for iron. No adverse findings were observed in ear tissue histopathology or in animal gross behavior. At 2 and 30 days after treatment, inflammatory changes examined in the ear were limited to the middle ear, were very mild in severity, and by day 90 there was ongoing and almost complete reversibility of these changes. There were no ear tissue scarring or hemorrhage trends associated with magnetic delivery. In summary, after conducting a pre-clinical safety study, no adverse safety issues were observed.

A rapid review of treatment literacy materials for tuberculosis patients

OBJECTIVE

To assess available treatment literacy materials for patients undergoing treatment for tuberculosis (TB).

DESIGN

We conducted a rapid review by searching the US Centers for Disease Control's Find TB Resources website and the websites of health departments and TB-focused organizations. We included English-language documents intended to educate TB patients about anti-tuberculosis treatment. We evaluated the format, readability, and content of documents, and audience. We defined 12 essential content elements based on those previously identified as facilitating human immunodeficiency virus treatment literacy.

RESULTS

Of the 205 documents obtained, 45 were included in our review. The median reading grade level was 7 (IQR 5-8). The median number of essential content elements present was 6 (IQR 4-8), with the most comprehensive document containing 11 of the 12 elements. Only two documents were written for children with TB or their care givers, and two for patients with drug-resistant TB. Many documents contained paternalistic and non-patient-centered language.

CONCLUSION

We found few examples of comprehensive, patient-centered documents. Work is needed to achieve consensus as to the essential elements of TB treatment literacy and to create additional materials for children, patients with drug-resistant TB, and those with lower literacy levels.