Refined high-content imaging-based phenotypic drug screening in zebrafish xenografts

Zebrafish xenotransplantation models are increasingly applied for phenotypic drug screening to identify small compounds for precision oncology. Larval zebrafish xenografts offer the opportunity to perform drug screens at high-throughput in a complex in vivo environment. However, the full potential of the larval zebrafish xenograft model has not yet been realized and several steps of the drug screening workflow still await automation to increase throughput. Here, we present a robust workflow for drug screening in zebrafish xenografts using high-content imaging. We established embedding methods for high-content imaging of xenografts in 96-well format over consecutive days. In addition, we provide strategies for automated imaging and analysis of zebrafish xenografts including automated tumor cell detection and tumor size analysis over time. We also compared commonly used injection sites and cell labeling dyes and show specific site requirements for tumor cells from different entities. We demonstrate that our setup allows us to investigate proliferation and response to small compounds in several zebrafish xenografts ranging from pediatric sarcomas and neuroblastoma to glioblastoma and leukemia. This fast and cost-efficient assay enables the quantification of anti-tumor efficacy of small compounds in large cohorts of a vertebrate model system in vivo. Our assay may aid in prioritizing compounds or compound combinations for further preclinical and clinical investigations.

Evidence for phosphorylation-dependent, dynamic, regulation of mGlu5 and Homer2 in expression of cocaine aversion in mice

Cocaine-induced changes in the expression of the glutamate-related scaffolding protein Homer2 influence this drug's psychostimulant and rewarding properties. In response to neuronal activity, Homer2 is phosphorylated on S117/S216 by calcium-calmodulin kinase IIα (CaMKIIα), which induces a rapid dissociation of mGlu5-Homer2 scaffolds. Herein, we examined the requirement for Homer2 phosphorylation in cocaine-induced changes in mGlu5-Homer2 coupling, to include behavioral sensitivity to cocaine. For this, mice with alanine point mutations at (S117/216)-Homer2 (Homer2^AA/AA ) were generated and we determined their affective, cognitive and sensorimotor phenotypes, as well as cocaine-induced changes in conditioned reward and motor hyperactivity. The Homer2^AA/AA mutation prevented activity-dependent phosphorylation of S216 Homer2 in cortical neurons, but Homer2^AA/AA mice did not differ from wild-type controls with respect to Morris maze performance, acoustic startle, spontaneous or cocaine-induced locomotion. Homer2^AA/AA mice exhibited signs of hypo-anxiety similar to the phenotype of transgenic mice with a deficit in signal-regulated mGluR5 phosphorylation (Grm5^AA/AA ). However, opposite of Grm5^AA/AA mice, Homer2^AA/AA mice were less sensitive to the aversive properties of high-dose cocaine under both place- and taste-conditioning procedures. Acute injection with cocaine caused dissociation of mGluR5 and Homer2 in striatal lysates from WT, but not Homer2^AA/AA mice, suggesting a molecular basis for the deficit in cocaine aversion. These findings indicate that CaMKIIα-dependent phosphorylation of Homer2 gates the negative motivational valence of high-dose cocaine via regulation of mGlu5 binding, furthering an important role for dynamic changes in mGlu5-Homer interactions in addiction vulnerability.Significance statementGlobally, psychostimulant use has again risen to reach epidemic proportions, particularly in the United States. Yet, we continue to face a knowledge gap regarding the biological bases of psychostimulant addiction vulnerability to inform disease prognosis and treatment-based recovery. Herein, we show that the psychomotor stimulant cocaine induces the uncoupling of the mGlu5 glutamate receptor from its scaffolding protein Homer2 in brain. Using a transgenic mouse model with deficits cocaine-induced uncoupling of mGlu5-Homer2, we demonstrate an important role for Homer2 scaffolding of mGlu5 in regulating cocaine's aversive properties, without influencing cocaine reward. Findings suggest that environmental factors, to include cocaine exposure, that affect mGlu5-Homer2 scaffolding dynamics may contribute to an individual's subjective response to cocaine to influence addiction vulnerability.

P07.04.B Heme biosynthesis factors and 5-ALA induced fluorescence: analysis of mRNA and protein expression in fluorescing and non-fluorescing gliomas

Background

The intraoperative visualization of adult-type diffuse gliomas with 5-aminolevulinic acid (5-ALA) induced fluorescence is widely used in the neurosurgical field. While visible 5-ALA induced fluorescence is found in the majority of high-grade gliomas, most low-grade gliomas lack visible fluorescence during surgery. Recently, the heme biosynthesis pathway was identified as crucial influencing factor for presence of visible fluorescence since it metabolizes 5-ALA to fluorescing Protoporphyrin IX (PpIX). However, the exact alterations within the heme biosynthesis pathway resulting in visible 5-ALA induced fluorescence in gliomas are still unclear. The aim of the present study was thus to compare the mRNA and protein expression of promising intramitochondrial heme biosynthesis enzymes/transporters in glioma tissue samples of different fluorescence behavior.

Material and Methods

A total of 19 strongly fluorescing and 21 non-fluorescing tissue samples from neurosurgical adult-type diffuse gliomas (WHO grades II-IV) were included in the current analysis. In these samples, we investigated the mRNA expression by quantitative real time PCR and protein expression using immunohistochemistry of the intramitochondrial heme biosynthesis enzymes Coproporphyrinogen Oxidase (CPOX), Protoporphyrinogen Oxidase (PPOX), Ferrochelatase (FECH) and the transporter ATP-binding Cassette Subfamily B Member 2 (ABCG2).

Results

Regarding mRNA expression analysis, we found a significantly decreased ABCG2 expression in fluorescing specimens compared to non-fluorescing samples (p=0.001), whereas no difference in CPOX, PPOX and FECH was present. With respect to protein expression, significantly higher levels of CPOX (p=0.005), PPOX (p<0.01) and FECH (p=0.003) were detected in fluorescing samples. Similar to mRNA expression analysis, the protein expression of ABCG2 (p=0.001) was significantly lower in fluorescing samples.

Conclusion

Distinct alterations of the analyzed heme biosynthesis factors were found primarily on protein level. Our data indicate that heme biosynthesis pathway activity in general is enhanced in fluorescing gliomas with upregulation of PpIX generating enzymes and decreased ABCG2 mediated PpIX efflux outweighing the also increased further metabolization of PpIX to heme. Intramitochondrial heme biosynthesis factors thus constitute promising pharmacological targets to optimize intraoperative 5-ALA fluorescence visualization of usually non-fluorescing tumors such as low-grade gliomas.

P14.04.A TrackingTERTpromoter andIDH1mutations in liquid biopsies - suitable biomarkers for disease monitoring in glioma patients?

Background

Mutations within the telomerase reverse transcriptase promoter (TERTprom) and isocitrate dehydrogenase (IDH) account for the most common genetic alterations in gliomas. Each of these mutations impact clinicopathologic diagnosis and course of diseases. While TERTprom mutations are frequently detected in glioblastoma, IHD mutations are assigned to astrocytoma of grade 2-4, thus mostly associated with better prognosis. In the era of precision oncology, molecular profiling and continuous monitoring of treatment response or relapse are of increasing importance. Accordingly, this study aims to detect TERTprom and IDH mutations in plasma-derived cell-free (cf)DNA of gliomas. The mutant allele frequencies (MAF) will be compared retrospectively to clinico-pathological parameters including extent of resection and tumor progression.

Material and Methods

Digital droplet PCR (ddPCR) analyses were performed using the QX200TM Digital Droplet System from BioRad. First, to evaluate probes for ddPCR, genomic DNA of several brain tumor cell models (n=6) and tumor tissue (n=1), as well as cfDNA of plasma (n=3) from samples with known TERTprom and IDH mutation status was investigated. For detection of IDH mutations, the unique assay ID dHSaMDV2010055 (IDH1p.R132H) and for TERTprom mutations the TaqMan dPCR Liquid Biopsy Assays for C228T (Hs000000092) and C250T (Hs000000093) were used. The results of ddPCR were analyzed with QuantaSoftTM software and the MAF was calculated

Results

To validate the detection method for IDH1R132H, we analyzed the MAF in one tissue and corresponding plasma sample of a confirmed IDH1-mutated astrocytoma. In addition, plasma from one astrocytoma grade 2-3 as well as from an IDH1-mutated glioblastoma was tested. Interestingly, both astrocytoma cases exhibited undetectable or very low MAF ranging from 0.1 to 1% in tissue as well as in plasma samples, while in plasma from the high-grade glioblastoma case, IDH1R132H was detected with a frequency of 1.9%. Due to the high GC content of the TERT promoter region, amplification steps are challenging. Accordingly, we first optimized ddPCR conditions for C228T and C250T probes by adding 7-deaza-2-deoxyguanosine-5-triphosphate (7-ddGTP) in varying concentrations to each ddPCR reaction. When using 4µM of 7-ddGTP per sample, a clear separation between mutant and wild-type droplets was reached, detecting MAF between 36-63% in DNA from cell culture models.

Conclusion

Within this pilot study we optimized the ddPCR method for the detection of IDH1R132H and TERTprom mutations in plasma and tissue samples. Subsequently, we hypothesize that these mutations are suitable liquid biomarkers correlating with extent of resection and tumor progression in gliomas.

P11.44.A The impact of heme biosynthesis regulation on glioma aggressiveness: correlations with most recent diagnostic molecular markers

Background

The prognosis of patients with diffusely infiltrating gliomas is dismal but varies greatly between individuals. While characterization of gliomas was primarily relied on typical histopathological features, specific molecular markers increasingly gained importance and play a key role in the recently published 5th edition of the World Health Organization (WHO) classification. Heme biosynthesis represents a crucial pathway due to its key role in oxygen transport, energy production or drug metabolism. Recently, we described a “heme biosynthesis mRNA expression signature” that correlates with histopathological glioma grades and patient survival. The aim of the current study was to correlate the heme biosynthesis mRNA expression signature with the most recent diagnostic molecular markers for glioma stratification.

Material and Methods

In this study, patient data were derived from the “The Cancer Genome Atlas” (TCGA) lower-grade glioma and glioblastoma cohorts. We identified diffusely infiltrating gliomas correlating molecular tumor diagnosis according to the most recent WHO classification with heme biosynthesis mRNA expression. The following molecular markers were analyzed: EGFR amplification, TERT promoter mutation, CDKN2A/B homozygous loss, concurrent chromosome 7 gain/10 loss, MGMT methylation, IDH mutation, ATRX loss, p53 mutation and 1p19q co-deletion. Subsequently, we calculated the heme biosynthesis mRNA expression signature and correlated this signature with distinct molecular glioma markers as well as the resulting molecular subgroups.

Results

A total of 649 patients with available data on up-to-date molecular markers and heme biosynthesis mRNA expression were included. According to analysis of individual molecular markers, we found a significantly higher heme biosynthesis mRNA expression signature in gliomas with IDH wildtype (p<0.0005), without 1p19q co-deletion (p<0.0005), with homozygous CDKN2A/B loss (p<0.0005) and with EGFR amplification (p=0.001). Furthermore, we observed that the heme biosynthesis mRNA expression signature increased with the aggressiveness of the molecular subgroups (p<0.0005), being lowest in WHO grade 2 oligodendrogliomas and highest in WHO grade 4 glioblastomas.

Conclusion

Our data demonstrate a significant correlation between diagnostic molecular markers and heme biosynthesis regulation in diffusely infiltrating gliomas. Consequently, heme biosynthesis expression is a promising biomarker for glioma aggressiveness and might constitute a potential target for novel therapeutic approaches.

P13.04.B Dissecting high-grade glioma immune infiltration in samples from fluorescence-guided surgery: digital pathology with automated image analysis

Background

Fluorescence-guided surgery with 5-aminolevulinic acid (5-ALA) is a widely used technique to conduct maximum safe resection of high-grade gliomas (HGG). 5-ALA accumulates in malignant tumor tissue where it is metabolized to Protoporphyrin IX (PpIX), an agent with fluorescence properties. It helps neurosurgeons to distinguish between tumor-infiltrated tissue and healthy brain parenchyma. Even though fluorescence-guided surgery is clinically well established, the biological properties of different fluorescence levels are not comprehensively studied yet. A relevant current gap in that respect is the pattern of immune cell infiltration in fluorescent versus non-fluorescent tissue samples. In light of future research, reliable, standardized histopathology methods that allow high-throughput analysis are desirable and digital pathology with automated image analysis is an attractive option to explore.

Material and Methods

128 formalin-fixed paraffin-embedded (FFPE) tissue blocks of 39 patients who underwent fluorescence-guided surgery of a HGG were included. Samples were selected based on their documented 5-ALA fluorescence intensity status (strong, vague, negative). Microtome-cut sections of the tissue were stained with antibodies against CD8, CD68, CD163 and FOX P3, representing immune cell populations of specific interest (cytotoxic T cells, glioma-associated macrophages, regulatory T cells). A total of 512 stained slides were then available for assessment. In addition to a classical, semi-quantitative analysis by two independent human reviewers, the immune infiltration intensity was measured via automated image analysis with the digital pathology software QuPath Version 0.3.2.

Results

Across all stained FFPE samples CD68 showed the overall highest intensity, followed by CD163. CD8 and FoxP3 showed generally lower average intensities. In 5-ALA negative and positive high-grade glioma samples the immune cell infiltration pattern was the same. Quantitative automatic digital pathology correlated well with the classical human histopathological analysis for the majority of markers evaluated.

Conclusion

We successfully explored and established novel digital pathology technologies for the study of immune cell infiltration patterns in neurooncology, specifically in the context of fluorescence-guided resection. Leveraging this platform could allow parallelized and high-throughput analysis of immune cell infiltration also in other contexts.

The effects of early pregnancy loss on health outcomes and health care utilization and costs

Objective

To evaluate the effects of early pregnancy loss on subsequent health care use and costs.

Data Sources

Linked administrative health databases from Manitoba, Canada.

Study Design

This was a population‐based cohort study. The exposure of interest was first recorded ectopic pregnancy or miscarriage (EPM). Outcomes included visits to all ambulatory care providers, family physicians (FPs), specialists, and hospitals, as well as the costs associated with these visits. We also assessed the impact of EPM on a global measure of health service utilization and the incidence and costs of psychotropic medications.

Data Collection/Extraction Methods

We identified women who experienced their first recorded loss (EPM) from 2003–2012 and created a propensity score model to match these women to women who experienced a live birth, with outcome measures available through 31 December 2014. We used a difference in differences approach with multivariable negative binomial models and generalized estimating equations (GEE) to assess the impact of EPM on the aforementioned health care utilization indicators.

Principal Findings

EPM was associated with a short‐term increase in visits to, and costs associated with, certain ambulatory care providers. These findings were driven in large part by increased visits/costs to FPs (rate difference [RD]: $19.92 [95% CI: $16.33, $23.51]) and obstetrician‐gynecologists (OB‐GYNs) (RD $9.41 [95% CI: $8.42, $10.40]) in the year immediately following the loss, excluding care associated with the loss itself. We also detected an increase in hospital stays and costs and a decrease in the use of psychotropic medications relative to matched controls.

Conclusion

Pregnancy loss may lead to subsequent increases in certain types of health care utilization. While the absolute costs associated with post‐EPM care are relatively small, the observed patterns of service utilization are informative for providers and policy makers seeking to support women following a loss.

KDM6A mutations promote acute cytoplasmic DNA release, DNA damage response and mitosis defects

Background

KDM6A, encoding a histone demethylase, is one of the top ten mutated epigenetic cancer genes. The effect of mutations on its structure and function are however poorly characterized.

Methods

Database search identified nonsense and missense mutations in the N-terminal TPR motifs and the C-terminal, catalytic JmjC domain, but also in the intrinsically disordered region connecting both these two well-structured domains. KDM6A variants with cancer-derived mutations were generated using site directed mutagenesis and fused to eGFP serving as an all-in-one affinity and fluorescence tag to study demethylase activity by an ELISA-based assay in vitro, apoptosis by FACS, complex assembly by Co-immunoprecipitation and localization by microscopy in urothelial cells and apoptosis by FACS.

Results

Independent of the mutation and demethylase activity, all KDM6A variants were detectable in the nucleus. Truncated KDM6A variants displayed changes in complex assemblies affecting (1) known interactions with the COMPASS complex component RBBP5 and (2) KDM6A-DNA associated assemblies with the nuclear protein Nucleophosmin. Some KDM6A variants induced a severe cellular phenotype characterized by multiple acute effects on nuclear integrity, namely, release of nuclear DNA into the cytoplasm, increased level of DNA damage indicators RAD51 and p-γH2A.X, and mitosis defects. These damaging effects were correlated with increased cell death.

Conclusion

These observations reveal novel effects of pathogenic variants pointing at new specific functions of KDM6A variants. The underlying mechanisms and affected pathways have to be investigated in future research to understand how tumor cells cope with and benefit from KDM6A truncations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12860-021-00394-2.

AB0040 PYRUVATE DEHYDROGENASE KINASES AS A POTENTIAL TARGET IN THE TREATMENT OF OSTEOARTHRITIS TO UNLEASH THE METABOLIC FLOW?

Background:

While osteoarthritis (OA) is the most common joint disease worldwide, rheumatoid arthritis (RA) represents the most common type of autoimmune arthritis. In both diseases, fibroblast-like synoviocytes (FLS), which maintain the structural and dynamic integrity of the joint, have been identified as key drivers of cartilage degradation. FLS can be divided into two major populations. The destructive phenotype which is restricted to the THY1- FLS of the synovial lining promotes bone erosion, while THY1+ FLS of the sublining layer drives synovitis. The FLS phenotype is shaped by glucose metabolism, which promotes disease progression in patients with synovitis. However, profound knowledge about the contribution of FLS to pathogenic mechanisms in cartilage degradation is limited.

Objectives:

Here, we present the phenotypic features of FLS obtained from patients with OA (OA-FLS) compared to bone marrow-derived mesenchymal stromal cells (MSC) on transcriptomic, proteomic and metabolic levels with the aims (i) to identify novel targets for the development of disease-modifying osteoarthritis drugs and (ii) to distinguish both cell types.

Methods:

To this end, we comprehensively compared human bone marrow-derived MSC with OA-FLS isolated from human knee joint sections. MSC and OA-FLS were characterized in detail according to their multipotency, surface marker pattern, cell viability, proliferation rate, morphology and expression of fibroblast- and metabolic-related markers using flow cytometry, immunofluorescence and SeahorseTM. More in-depth, selected gene and protein expression patterns were analyzed using qPCR and mass spectrometry.

Results:

We observed a similar phenotype of OA-FLS and MSC with regard to the minimal criteria that define a MSC phenotype. In-depth comparison of OA-FLS and MSC on proteome level revealed 598 differentially expressed proteins. We observed no differences in the expression of classical fibroblast markers such as vimentin, tenascin C and decorin as confirmed on RNA level. Remarkably, fibronectin, which is mainly produced by fibroblasts, is significantly lower expressed at both protein and RNA levels in OA-FLS together with collagen type 1 and CD106. Conversely, CD9, CD54 and fibroblast-specific protein-1 were expressed significantly higher in FLS at both levels, while hyaluronan synthase 1-3 remained unchanged. Of note, in terms of mitochondrial function, human OA-FLS show a significantly lower basal respiration and ATP production than MSC, but a comparable spare respiratory capacity and cellular mitochondrial dehydrogenase activity (NADH amount) per cell. Additionally, we identified the pyruvate dehydrogenase kinase (PDK) 3 to be highly expressed in OA-FLS, while the expression of mitochondrial ATP synthase subunits, electron transport chain complexes and glycolytic enzymes was comparable with MSC. Finally, inhibition of PDK by using DCA resulted in a significant increase in oxygen consumption rate and ATP production in OA-FLS. Thus, our data newly suggest, that PDKs may play a crucial role in the pathogenesis of OA and possibly RA.

Conclusion:

Our data provide evidence that, although the classical fibroblast markers do not discriminate between MSC and FLS, the latter demonstrate a significantly higher expression of PDKs, known to inhibit the pyruvate entry into the TCA cycle which finally limits the mitochondrial ATP production. Therefore, shifting the metabolism of FLS from glycolysis to mitochondrial respiration via inhibition of PDKs might be a novel approach in OA for the development of disease-modifying osteoarthritis drugs in order to unleash the metabolic flow.

Disclosure of Interests:

None declared

Combining segmental bulk- and single-cell RNA-sequencing to define the chondrocyte gene expression signature in the murine knee joint

OBJECTIVE

Due to the small size of the murine knee joint, extracting the chondrocyte transcriptome from articular cartilage (AC) is a major technical challenge. In this study, we demonstrate a new pragmatic approach of combining bulk RNA-sequencing (RNA-seq) and single cell (sc)RNA-seq to address this problem.

DESIGN

We propose a new cutting strategy for the murine femur which produces three segments with a predictable mixed cell population, where one segment contains AC and growth plate (GP) chondrocytes, another GP chondrocytes, and the last segment only bone and bone marrow. We analysed the bulk RNA-seq of the different segments to find distinct genes between the segments. The segment containing AC chondrocytes was digested and analysed via scRNA-seq.

RESULTS

Differential expression analysis using bulk RNA-seq identified 350 candidate chondrocyte gene in the AC segment. Gene set enrichment analysis of these genes revealed biological processes related- and non-related to chondrocytes, including, cartilage development (adj. P-value: 3.45E-17) and endochondral bone growth (adj. P-value 1.22E-4), respectively. ScRNA-seq of the AC segment found a cluster of 131 cells containing mainly chondrocytes. This cluster had 759 differentially expressed genes which enriched for extracellular matrix organisation (adj. P-value 7.76E-40) and other joint development processes. The intersection of the gene sets of bulk- and scRNA-seq contained 75 genes.

CONCLUSIONS

Based on our results, we conclude that the combination of the two RNA-seq methods is necessary to precisely delineate the chondrocyte transcriptome and to study the disease phenotypes of chondrocytes in murine OA models in the future.

Fire safety and emergency evacuation guidelines for intensive care units and operating theatres: for use in the event of fire, flood, power cut, oxygen supply failure, noxious gas, structural collapse or other critical incidents: Guidelines from the Association of Anaesthetists and the Intensive Care Society

The need to evacuate an ICU or operating theatre complex during a fire or other emergency is a rare event but one potentially fraught with difficulty: Not only is there a risk that patients may come to harm but also that staff may be injured and unable to work. Designing newly-built or refurbished ICUs and operating theatre suites is an opportunity to incorporate mandatory fire safety features and improve the management and outcomes of such emergencies: These include well-marked manual fire call points and oxygen shut off valves (area valve service units); the ability to isolate individual zones; multiple clear exit routes; small bays or side rooms; preference for ground floor ICU location and interconnecting routes with operating theatres; separate clinical and non-clinical areas. ICUs and operating theatre suites should have a bespoke emergency evacuation plan and route map that is readily available. Staff should receive practical fire and evacuation training in their clinical area of work on induction and annually as part of mandatory training, including 'walk-through practice' or simulation training and location of manual fire call points and fire extinguishers, evacuation routes and location and operation of area valve service units. The staff member in charge of each shift should be able to select and operate fire extinguishers and lead an evacuation. Following an emergency evacuation, a network-wide response should be activated, including retrieval and transport of patients to other ICUs if needed. A full investigation should take place and ongoing support and follow-up of staff provided.

136 Readmissions to Hospital Following A Decision to Eat and Drink with Acknowledged Risk with Support From the Forward Care Bundle

Introduction

The FORWARD care bundle (Feeding via the Oral Route With Acknowledged Risk of Deterioration) is used to support patients with dysphagia eating and drinking with acknowledged risk (EDAR) at our Trust. Key aims of FORWARD include improving advanced care planning (ACP) and avoiding unnecessary readmissions. This study aimed to determine the incidence of EDAR related readmissions (RR-EDAR) after FORWARD, and the effects of ACP and discharge location.

Methods

Retrospective review of all patients supported by FORWARD during admissions between January 2018 and December 2019. Data were collected on number and reasons for in-Trust hospital readmissions 6 months post-discharge, preferred place of care ACPs in event of EDAR related deterioration and discharge destination. Readmission reasons were classified as RR-EDAR (e.g. chest infection, reduced oral intake) and no relation to EDAR. Means (SD) and percentages are presented with comparisons using Fishers Exact Test.

Results

316 patients were included; mean (SD) age 81(12). 64% (n = 202) of patients were discharged alive, 36% (n = 114) were alive at 6 months. 38% of live discharges (n = 75) were readmitted and 52% (n = 39) of these patients were RR-EDAR. Mean (SD) RR-EDAR number was 11, and 18% (n = 7) of patients had RR-EDAR >1 (range 1–5). RR-EDAR was only 7% (n = 4) in patients wishing to remain at home vs 25% (n = 33) in those without a documented place of care (p < 0.01). RR-EDAR was 23% (n = 29) in patients discharged to a private home vs 10% (n = 6) discharged to nursing/care homes (p < 0.05).

Conclusions

The majority of FORWARD patients are not readmitted. RR-EDAR comprises half of all readmitted patients and some have multiple admissions. Fewer patients with ACPs were RR-EDAR suggesting these are effective. Most patients RR-EDAR were from private homes, suggesting residential care may provide more support. Further work includes increasing ACPs, supporting patients with multiple RR-EDAR and those discharged to private homes.

THU0069 MIMICKING ARTHRITIS IN VITRO TO TEST DIFFERENT TREATMENT APPROACHES

Background:

Our ultimate goal is to study potential drug candidates in an experimental setting of arthritis. Therefore, we aim to develop a valid humanin vitro3D joint model mimicking features of joint inflammation by applying inflammatory conditions namely immune cells and pro-inflammatory cytokines. Our in vitro3D joint model consists of different components including an osteogenic and chondrogenic part, the joint space filled with synovial fluid, and the synovial membrane. Developed as an alternative experimental setup to animal experiments, our 3D joint model will enable us to study efficiently the effects of potential drug candidates in a human-basedin vitromodel.

Objectives:

Here, we aimed to demonstrate the suitability of our human-basedin vitro3D osteochondral model by analyzing the influence of the main cytokines involved in the pathogenesis of RA as well as the impact of a specific therapeutic intervention.

Methods:

Based on human bone marrow-derived mesenchymal stromal cells (hMSCs), we developed 3D bone and cartilage tissue components that were characterized in detail (e.g. cell vitality, morphology, structural integrity) using histological, biochemical and molecular biological methods as well as µCT and scanning electron microscope (SEM). In brief, to establish the osteogenic component, we populated β-tricalcium phosphate (TCP) – mimicking the mineral bony part – with hMSCs, while the scaffold-free cartilage component was generated by cellular self-assembly and intermittent mechanical stimulation (fzmb GmbH). Subsequently, we co-cultivated both tissue components for three weeks to generate an interconnected 3D osteochondral model. To test the suitability, we applied a cocktail of TNFα, IL-6 and MIF using concentrations reported from RA synovial fluid alone or in combination with specific therapeutic drugs and analyzed their impact by qPCR.

Results:

We verified the osteogenic phenotype of our 3D bone tissue component by demonstrating an increase in mineralized bone volume and the induction of bone-related gene expression (RUNX2,SPP1andCOL1A1) as compared to the corresponding control. Secondly, we verified the chondrogenic phenotype of our cartilage tissue component by HE and Alcian Blue staining as well as by the reduced expression ofCOL1A1and an abundant expression ofCOL2A1. Interestingly, co-cultivation of both components for up to 3 weeks demonstrated colonization, connectivity and initial calcification implying a transitional bridging area. Cytokine stimulation with a cocktail of TNF, IL-6 and MIF leads to an upregulation of the metabolic markerLDHAand the angiogenic markerVEGFin both bone and cartilage. The inflammation markersIL8andTNFare also upregulated in both components, whileIL6is downregulated in bone compared to the unstimulated control. In addition, a cytokine-induced upregulation of matrix-metalloproteases was observed especially in the cartilage component. All these cytokine-related effects could be antagonized with a cocktail of therapeutics (milatuzumab, adalimumab and tocilizumab).

Conclusion:

The results of our study showed cytokine related effects of both tissue components, which can be therapeutically antagonized. By combining the components in a 96 well format, we aim to provide a mid-throughput system for preclinical drug testing.

Acknowledgments:

This project is funded by the Federal Ministery of Education and Research (BMBF)

Disclosure of Interests:

Alexandra Damerau: None declared, Moritz Pfeiffenberger: None declared, Annemarie Lang: None declared, Timo Gaber: None declared, Frank Buttgereit Grant/research support from: Amgen, BMS, Celgene, Generic Assays, GSK, Hexal, Horizon, Lilly, medac, Mundipharma, Novartis, Pfizer, Roche, and Sanofi.

OP0244 A PRECLINICAL TESTING TOOL: THE IN VITRO 3D FRACTURE GAP MODEL

Background:

Approximately 10% of fractures lead to significant fracture healing disorders, with a tendency to further increase due to the aging population. Of note, especially immunosuppressed patients with ongoing inflammation show difficulties in the correct course of fracture healing leading to fracture healing disorders. Most notably, invading immune cells and secreted cytokines are considered to provide an inflammatory microenvironment within the fracture gap, primarily during the initial phase of fracture healing. Current research has the focus on small animal models, facing the problem of translation towards the human system. In order to improve the therapy of fracture healing disorders, we have developed a human cell-basedin vitromodel to mimic the initial phase of fracture healing adequately. This model will be used for the development of new therapeutic strategies.

Objectives:

Our aim is to develop anin vitro3D fracture gap model (FG model) which mimics thein vivosituation in order to provide a reliable preclinical test system for fracture healing disorders.

Methods:

To assemble our FG model, we co-cultivated coagulated peripheral blood and primary human mesenchymal stromal cells (MSCs) mimicking the fracture hematoma (FH model) together with a scaffold-free bone-like construct mimicking the bony part of the fracture gap for 48 h under hypoxic conditions (n=3), in order to reflect thein vivosituation after fracture most adequately. To analyze the impact of the bone-like construct on thein vitroFH model with regard to its osteogenic induction capacity, we cultivated the fracture gap models in either medium with or without osteogenic supplements. To analyze the impact of Deferoxamine (DFO, known to foster fracture healing) on the FG model, we further treated our FG models with either 250 µmol DFO or left them untreated. After incubation and subsequent preparation of the fracture hematomas, we evaluated gene expression of osteogenic (RUNX2,SPP1), angiogenic (VEGF,IL8), inflammatory markers (IL6,IL8) and markers for the adaptation towards hypoxia (LDHA,PGK1) as well as secretion of cytokines/chemokines using quantitative PCR and multiplex suspension assay, respectively.

Results:

We found via histology that both the fracture hematoma model and the bone-like construct had close contact during the incubation, allowing the cells to interact with each other through direct cell-cell contact, signal molecules or metabolites. Additionally, we could show that the bone-like constructs induced the upregulation of osteogenic markers (RUNX2, SPP1) within the FH models irrespective of the supplementation of osteogenic supplements. Furthermore, we observed an upregulation of hypoxia-related, angiogenic and osteogenic markers (RUNX2,SPP1) under the influence of DFO, and the downregulation of inflammatory markers (IL6,IL8) as compared to the untreated control. The latter was also confirmed on protein level (e.g. IL-6 and IL-8). Within the bone-like constructs, we observed an upregulation of angiogenic markers (RNA-expression ofVEGF,IL8), even more pronounced under the treatment of DFO.

Conclusion:

In summary, our findings demonstrate that our establishedin vitroFG model provides all osteogenic cues to induce the initial bone healing process, which could be enhanced by the fracture-healing promoting substance DFO. Therefore, we conclude that our model is indeed able to mimic correctly the human fracture gap situation and is therefore suitable to study the influence and efficacy of potential therapeutics for the treatment of bone healing disorders in immunosuppressed patients with ongoing inflammation.

Disclosure of Interests:

Moritz Pfeiffenberger: None declared, Alexandra Damerau: None declared, Paula Hoff: None declared, Annemarie Lang: None declared, Frank Buttgereit Grant/research support from: Amgen, BMS, Celgene, Generic Assays, GSK, Hexal, Horizon, Lilly, medac, Mundipharma, Novartis, Pfizer, Roche, and Sanofi., Timo Gaber: None declared

FRI0369 MIMICKING GLUCOCORTICOID-INDUCED OSTEOPOROSIS USING AN IN VITRO TRABECULAR HUMAN BONE MODEL

Background:

The bone matrix consists of inorganic and organic components and a variety of specialized cells such as osteoblasts, osteocytes and osteoclasts. The bone-forming osteoblasts are responsible for the production of organic matrix components; they differentiate later into osteocytes which is accompanied by matrix mineralization. Osteoclasts are multinuclear giant cells, which resorb bone. Healthy bone homeostasis is characterized by a balanced, dynamic and continuous remodeling process. Glucocorticoids (GCs) are commonly used to successfully treat patients with inflammatory rheumatic and other autoimmune diseases. However, long-term treatment with GC can potentially lead to several adverse effects such as the inhibition of osteoblast proliferation and the increase of osteoclastic activity resulting in osteoporosis.

Objectives:

Hence, the aim of our project is to i) develop anin vitrotrabecular human bone model, ii) integrate this bone model into a perfusion system to accelerate mineralization and provide biomechanical stimuli and iii) applying prednisolone to induce osteoporosis. Here we present our initial results describing the successful differentiation of osteoblasts and osteoclasts in a 3D environment, and the accomplished integration of the bone model into a perfusion system.

Methods:

In a first step, different cultivation conditions were tested to allow optimal osteogenic or osteoclastic differentiation. To this end, a) human bone marrow derived mesenchymal stromal cells (hMSCs) were treated with osteogenic medium, and b) monocytes (isolated from buffy coats) were differentiated into osteoclasts using following protocol: incubation for 3 days with 25 ng/ml M-CSF followed by an 18-day incubation with M-CSF and 50 ng/ml RANKL. Calcification of hMSCs was evaluated via Alizarin Red S staining. Osteoclasts were identified using immunofluorescence staining observing multinucleated (DAPI) giant (ß-Actin) cells with TRAP and Cathepsin K activity. Additional gene expression analyses are currently conducted using qRT-PCR and looking for osteoclast-specific genes. In parallel to the monolayer cultures, cells were transferred on β-tricalcium phosphate (βTCP) – a suitable bony-like scaffold. Furthermore, first experiments in a dynamic bioreactor platform (OSPIN GmH) were conducted to evaluate the influence of shear stress on the cells and model systems.

Results:

We have been able to populate the βTCP scaffold with monocytes, which were differentiated into osteoclasts (morphological changes) without any effect on cellular viability as measured by Live/Dead staining. The morphological changes of those osteoclasts such as formation of filopodia could be demonstrated by scanning electron microscopy. In addition, the cultivation of βTCP populated with hMSCs in a perfusion system showed the upregulation of osteogenic markers (RUNX2, OSX) on mRNA-level.

Conclusion:

These first results of our approach to develop anin vitro3D model for glucocorticoid-induced osteoporosis are promising. Our next step will be the co-cultivation of osteoblasts and osteoclasts under dynamic and optimized cultivation conditions. By combining several cell types, a suitable scaffold and biomechanical stimuli (perfusion), we aim to provide a valid testing platform to study underlying disease mechanisms and for drug development.

Acknowledgments:

The project has been funded by the Elsbeth Bonhoff Foundation.

Disclosure of Interests:

Annemarie Lang: None declared, Karoline Diesing: None declared, Alexandra Damerau: None declared, Sümeyye Uzun: None declared, Moritz Pfeiffenberger: None declared, Timo Gaber: None declared, Frank Buttgereit Grant/research support from: Amgen, BMS, Celgene, Generic Assays, GSK, Hexal, Horizon, Lilly, medac, Mundipharma, Novartis, Pfizer, Roche, and Sanofi.

Contingent negative variation: a biomarker of abnormal attention in functional movement disorders

BACKGROUND AND PURPOSE

Contingent negative variation (CNV) is a negative cortical wave that precedes a pre-cued imperative stimulus requiring a quick motor response. It has been related to motor preparation and anticipatory attention. The aim was to ascertain whether the clinical improvement of functional movement disorders after physiotherapy would be associated with faster reaction times and modulation of CNV.

METHODS

Motor performance and CNV were analysed during a pre-cued choice reaction time task with varying cue validity. Twenty-one patients with functional movement disorders and 13 healthy controls at baseline were compared. Patients then underwent physiotherapy. At follow-up after physiotherapy, patients were categorized as clinically improved (responders) or not improved (non-responders) and retested.

RESULTS

At baseline, patients did not generate CNV, contrary to controls [mean amplitude (µV) at the end of preparation to move: patients -0.47 (95% CI -1.94, 1.00) versus controls -2.59 (95% CI -4.46, -0.72)]. Responders performed faster after physiotherapy [mean natural logarithm (ln) reaction time (RT) (ms): follow-up 6.112 (95% CI 5.923, 6.301) versus baseline 6.206 (95% CI 6.019, 6.394), P = 0.010], contrary to non-responders. Simultaneously, responders showed a recovery of CNV after physiotherapy [follow-up -1.95 (95% CI -3.49, -0.41) versus baseline -0.19 (95% CI -1.73, 1.35), P < 0.001], contrary to non-responders [follow-up -0.32 (95% CI -1.79, 1.14) versus baseline -0.72 (95% CI -2.19, 0.75), P = 0.381].

CONCLUSIONS

Clinical improvement of functional movement disorders after physiotherapy was associated with faster reaction times and normalization of CNV, which was absent at baseline. These findings suggest that CNV may constitute a useful neurophysiological biomarker related to abnormal attention in functional movement disorders.

A156 LOW COMPLICATION RATE IN THE OUTPATIENT INTRAJEJUNAL LEVODOPA/CARBIDOPA INTESTINAL GEL CLINICAL PROGRAM

Background

Levodopa/carbidopa intestinal gel (LCIG) is a formulation that is delivered continuously through a percutaneous endoscopy gastro-jejunal tube (PEG-J) for the treatment of patients with advanced Parkinson’s disease (PD). LCIG significantly reduces periods of increased motor symptoms without troublesome dyskinesia. Adverse events related to this treatment have been attributed to PEG-J insertion and the device used for LCIG delivery, rather than to the LCIG preparation itself. To date, the data evaluating long-term efficacy and safety of PEG-J insertion for LCIG administration in the outpatient setting is limited.

Aims

The aim of this study is to describe short and long-term adverse events (AEs) associated with outpatient PEG-J tube insertion for LCIG administration at our centre.

Methods

A retrospective chart review was performed of all PD patients who underwent PEG-J insertion for LCIG therapy at Toronto Western Hospital from March 2011 to October 2019. All AEs associated with PEG-J insertion were collected including procedure and tube related complications, hospital admissions, emergency room (ER) visits and deaths. Data was analyzed using descriptive statistics.

Results

A total of 58 patients were identified and included in the final analysis. 37 (64%) male, with a mean age of 74 years +/-6.17. The mean duration of PD diagnosis prior to PEG-J insertion was 16.5 years +/-2.0. Mean time from PEG-J insertion to data collection was 37.5 months +/- 19.3. 30 (51%) patients had post-procedural abdominal pain or site pain. This pain improved with over the counter analgesics. 9 (16%) had possible site infection; 6 received oral antibiotics and 3 had the tube replaced. 19 (33%) developed granulation tissue, with only 2 patients requiring tube exchange. 32 (55%) had their tube removed or exchanged secondary to PEG-J malfunction. No ER visits related to the PEG-J were recorded. During the data collection period, 12 (21%) patients died for reasons unrelated to PEG-J insertion. There were no reported serious adverse events (SAEs), including post-procedure perforation, bleeding, fistula formation, development of intra-abdominal collections or buried bumper syndrome.

Conclusions

This study demonstrates the absence of serious AEs associated with outpatient PEG-J insertion for LCIG administration in patients with advanced PD. The most common short-term AE was post-procedural pain. The most common long-term AE was related to PEG-J malfunction requiring replacement. This study supports that the current method of outpatient PEG-J insertion for the administration of LCIG is safe in patients with advanced PD.

Funding Agencies

None

99 Approaches to Eating and Drinking with Acknowledged Risk: A Systematic Review

Introduction

Patients with dysphagia may consider eating and drinking with acknowledged risk (EDAR) instead of artificial hydration/nutrition. Timely consideration of complex issues is required including dysphagia reversibility, prognosis, risk/benefit discussions, patient wishes, their capacity, best interests and advanced care planning. This study aimed to ascertain if EDAR protocols improve care through a systematic literature review.

Methods

PUBMED, MEDLINE, CINAHL and EMBASE were searched for English language articles to May ‘19 with terms related to EDAR, dysphagia and end of life. Articles and conference abstracts with original data were agreed for inclusion by two independent reviewers. Levels of evidence were assessed using the Sackett scale (Cook et al, Chest. 1995; 4: 227–230). Study themes were identified and discussed.

Results

12 articles met the inclusion criteria with varied methodology. The highest level of evidence was III (cohort study) and most were limited to patients with dementia, stroke, in older person’s wards or residential homes. 4 articles described a systematic approach to EDAR for in-patients and reported reductions in days nil-by-mouth until feeding plans are made and improvements in documentation of decision making, nutrition plans and capacity assessment. Other major themes included the need for an EDAR protocol, staff, patient and carer/family knowledge of EDAR, development of a protocol and the language of “risk feeding”. Formal meta-analysis was not possible due to the level and mix of methodology.

Conclusions

There is a paucity of evidence to determine if EDAR protocols improve care. However support is emerging for a coordinated approach to managing EDAR. Findings suggest having a protocol is not enough; education, training and communication within teams and with patients and carers is essential and this justifies further work. The lack of research into the impact of EDAR protocols on patient and carer experience means they must be central to any future work.

Respiratory symptoms, asthma and levels of fractional exhaled nitric oxide in schoolchildren in the industrial areas of Estonia

OBJECTIVES

Exposure to air pollutants in the ambient environment has been associated with various respiratory symptoms, and with increased asthma diagnosis, in both children and adults. Most research to date has focussed on core pollutants, such as PM₁₀, PM_2.5, SO₂ and NO₂, and less attention has been given to the effects of industry-specific contamination. The current study aimed to examine the associations between respiratory symptoms, asthma, increased levels of fractional exhaled nitric oxide (FeNO) (as a marker of eosinophilic airway inflammation) and ambient levels of industrial pollutants (such as benzene, phenol, formaldehyde and non-methane hydrocarbons) for schoolchildren living near oil shale industries in Ida-Viru County, Estonia.

METHODS

A total of 1326 schoolchildren from Ida-Viru, Lääne-Viru and Tartu Counties participated in a cross-sectional study, consisting of questionnaires on respiratory symptoms and asthma, as well as clinical examinations to measure FeNO. Dispersion modelling was used to characterize individual-level exposure to industrial air pollutants at each subject's home address. Associations between exposure and respiratory health were investigated using logistic regression analysis, and differences in results between regions were analysed using the Chi-squared test.

RESULTS

The prevalence of respiratory symptoms (p < 0.05) in children living near (i.e. within 5 km) of an oil shale industry site in Ida-Viru County was 2-4 times higher than in children living in the reference area of Tartu County. Children exposed to 1 μg/m³ higher levels of benzene and formaldehyde had a higher odds ratio (OR) of having rhinitis without a cold (OR 1.03, 95% confidence interval (CI) 1.01-1.06), of ever having had attacks of asthma (OR 1.05, 95% CI 1.01-1.10) and of having a dry cough a few days per year (OR 1.05, 95% CI 1.01-1.10). Children exposed to 1 μg/m³ higher levels of benzene, formaldehyde, phenol and non-methane hydrocarbons had a higher odds ratio of having high FeNO levels (≥30 ppb): OR and 95% CI of 1.05, 1.01-1.09; 1.22, 1.06-1.41; 1.01, 1.00-1.01; and 1.75, 1.75-2.62, respectively.

Review of the surface architecture of the equine neopallium: Principle elements of a cartographic pattern of sulci revisited and further elaborated

The surface architecture of the equine telencephalon is far more complex and complicated than, for example, that of the carnivore's brain, and basic organization patterns are more difficult to recognize. This is due to species differences, to interindividual variations and even to asymmetries between right and left hemispheres. Moreover, a very heterogeneous anatomical terminology, especially in the pioneering older literature, does not allow easy access to a unanimous topographical orientation. This review article presents the key features of this heterogeneity and its anatomical and terminological backgrounds, focusing on the cerebral sulci. The abundant, often divergent data from the reviewed literature are displayed by means of graphical illustrations highlighting the key issues and comparing them with the terminology of the present Nomina Anatomica Veterinaria. These illustrations are supposed to convey the relevant conformities and discrepancies regarding locations, courses and names of cerebral sulci in an easier and more effective manner than written texts could possibly do with such a complex and heterogeneous matter. The data from the selected literature are supplemented by and discussed together with photographs and drawings of brains from our own collection. This combination of a classic review article and own findings is supposed to confirm, to further elaborate and to evaluate the key sulci serving as landmarks for an orientation on the equine neopallium. These are, laterally, the Sulcus suprasylvius, coronalis and praesylvius; dorsally, the Sulcus marginalis; and medially, the Sulcus genualis, cinguli and splenialis. Special attention is also given to the Fissura sylvia; a Fissura sylvia accessoria is proposed.

Excited state dynamics and conformations of a Cu(ii)-phthalocyanine-perylenebisimide dyad

We investigate the excited state dynamics and the conformations of a new molecular donor-bridge-acceptor system, a Cu(ii)-phthalocyanine (CuPc) covalently linked via a flexible aliphatic spacer to a perylenebisimide (PBI). We performed time-resolved polarization anisotropy and pump-probe measurements in combination with molecular dynamics simulations. Our data suggest the existence of three conformations of the dyad: two more extended, metastable conformations with centre-of-mass distances >1 nm between the PBI and CuPc units of the dyad, and a highly stable folded structure, in which the PBI and CuPc units are stacked on top of each other with a centre-of-mass distance of 0.4 nm. In the extended conformations the dyad shows emission predominantly from the PBI unit with a very weak contribution from the CuPc unit. In contrast, for the folded conformation the PBI emission of the dyad is strongly quenched due to fast energy transfer from the PBI to the CuPc unit (3 ps) and subsequent intersystem-crossing (300 fs) from the first excited singlet state of CuPc unit into its triplet state. Finally, the CuPc triplet state is deactivated non-radiatively with a time constant of 25 ns.

Immunological characterization of the early human fracture hematoma

The initial inflammatory phase of fracture healing is of great importance for the clinical outcome. We aimed to develop a detailed time-dependent analysis of the initial fracture hematoma. We analyzed the composition of immune cell subpopulations by flow cytometry and the concentration of cytokines and chemokines by bioplex in 42 samples from human fractures of long bones <72 h post-trauma. The early human fracture hematoma is characterized by maturation of granulocytes and migration of monocytes/macrophages and hematopoietic stem cells. Both T helper cells and cytotoxic T cells proliferate within the fracture hematoma and/or migrate to the fracture site. Humoral immunity characteristics comprise high concentration of pro-inflammatory cytokines such as IL-6, IL-8, IFNγ and TNFα, but also elevated concentration of anti-inflammatory cytokines, e.g., IL-1 receptor antagonist and IL-10. Furthermore, we found that cells of the fracture hematoma represent a source for key chemokines. Even under the bioenergetically restricted conditions that exist in the initial fracture hematoma, immune cells are not only present, but also survive, mature, function and migrate. They secrete a cytokine/chemokine cocktail that contributes to the onset of regeneration. We hypothesize that this specific microenvironment of the initial fracture hematoma is among the crucial factors that determine fracture healing.

Addition of an immunomodulator can reverse antibody formation and loss of response in patients treated with adalimumab

BACKGROUND

Anti-adalimumab antibodies (AAA) are associated with loss of clinical response (LOR). Addition of an immunomodulator has been shown to reverse immunogenicity and regain response with infliximab monotherapy. Similar data on adalimumab are lacking.

AIM

To study the impact of immunomodulator addition on the emergence of AAA and LOR among adalimumab therapy patients.

METHODS

The databases of three tertiary medical centres were reviewed to identify patients who developed AAA during adalimumab monotherapy with resultant LOR, and received an immunomodulator as a salvage combination therapy. All sera were prospectively analysed using previously described ELISA assays. Clinical response was determined using appropriate clinical scores. Elimination of AAA, designated as 'sero-reversal', elevation of drug levels and regained clinical response were the sought outcomes.

RESULTS

Twenty-three patients (21 Crohn's disease, and 2 ulcerative colitis) developed AAA with subsequent LOR and were thereafter prescribed an immunomodulator as salvage therapy (thiopurine n = 14, methotrexate n = 9). Eleven patients (48%) underwent sero-reversal with gradual elimination of AAA, increase in drug trough levels and restoration of clinical response (median time to sero-reversal 5 months). In 12 patients (52%), immunogenicity and loss of response could not be reversed. There was no difference between responders and nonresponders in the type of immunomodulators used or baseline clinical characteristics.

CONCLUSIONS

In almost half of inflammatory bowel disease patients developing anti-adalimumab antibodies and loss of response, established immunogenicity of adalimumab can be gradually reversed by the addition of immunomodulator therapy with restoration of a clinico-biological response. However, these observations need to be confirmed with larger studies.

Addition of an immunomodulator can reverse antibody formation and loss of response in patients treated with adalimumab

BACKGROUND

Anti-adalimumab antibodies (AAA) are associated with loss of clinical response (LOR). Addition of an immunomodulator has been shown to reverse immunogenicity and regain response with infliximab monotherapy. Similar data on adalimumab are lacking.

AIM

To study the impact of immunomodulator addition on the emergence of AAA and LOR among adalimumab therapy patients.

METHODS

The databases of three tertiary medical centres were reviewed to identify patients who developed AAA during adalimumab monotherapy with resultant LOR, and received an immunomodulator as a salvage combination therapy. All sera were prospectively analysed using previously described ELISA assays. Clinical response was determined using appropriate clinical scores. Elimination of AAA, designated as 'sero-reversal', elevation of drug levels and regained clinical response were the sought outcomes.

RESULTS

Twenty-three patients (21 Crohn's disease, and 2 ulcerative colitis) developed AAA with subsequent LOR and were thereafter prescribed an immunomodulator as salvage therapy (thiopurine n = 14, methotrexate n = 9). Eleven patients (48%) underwent sero-reversal with gradual elimination of AAA, increase in drug trough levels and restoration of clinical response (median time to sero-reversal 5 months). In 12 patients (52%), immunogenicity and loss of response could not be reversed. There was no difference between responders and nonresponders in the type of immunomodulators used or baseline clinical characteristics.

CONCLUSIONS

In almost half of inflammatory bowel disease patients developing anti-adalimumab antibodies and loss of response, established immunogenicity of adalimumab can be gradually reversed by the addition of immunomodulator therapy with restoration of a clinico-biological response. However, these observations need to be confirmed with larger studies.

The challenge of extra-intra craniometry: a computer-assisted three-dimensional approach on the equine skull

BACKGROUND

The topographical correlations between certain extracranial and intracranial osseous points of interest (POIs), and their age-related changes, are indispensable to know for a diagnostical or surgical access to intracranial structures; however, they are difficult to assess with conventional devices.

MATERIALS AND METHODS

In this pilot study, the 3-dimensional coordinates of extra-/intracranial POIs were determined, thus avoiding perspective distortions that used to be intrinsic problems in 2-dimensional morphometry. The data sets were then analysed by creating virtual triangles. The sizes, shapes, and positions of these triangles described the extent and the directions of the age-related shifts of the POIs. A selection of extracranial and intracranial POIs were marked on half skulls of four warmblood horses in two age groups (young: 6 weeks, n = 2; old: 14 and 17 years, n = 2). The x-, y-, and z-coordinates of these POIs were determined with a measurement arm (FaroArm Fusion, FARO Europe®). Direct distances between the POIs as well as their indirect distances on the x-, y-, and z-axis, and angles were calculated.

RESULTS

The analysed virtual triangles revealed that some parts of the skull grew in size, but did not change in shape/relative proportions (proportional type of growth, as displayed by POI A and POI B at the Arcus zygomaticus). The same POIs (A and B) remained in a very stable relationship to their closest intracranial POI at the Basis cranii on the longitudinal axis, however, shifted markedly in the dorso-lateral direction. In contrast, a disproportional growth of other parts of the cranium was, for example, related to POI C at the Crista nuchae, which shifted strongly in the caudal direction with age. A topographically stable reference point (so-called anchor point) at the Basis cranii was difficult to determine.

CONCLUSIONS

Two candidates (one at the Synchondrosis intersphenoidalis, another one at the Synchondrosis sphenooccipitalis) were relatively stable in their positions. However, the epicentre of (neuro-)cranial growth could only be pinpointed to an area between them.

Abstract P4-14-11: Efficacy and cardiac safety in neoadjuvant treatment of Her2 positive breast cancer with concomitant nonpegylated liposomal doxorubicin, docetaxel and dual blockade with trastuzumab and pertuzumab: A retrospective analysis

Background: Approval to pertuzumab as part of a complete treatment regimen for patients with early stage breast cancer (EBC) before surgery (neoadjuvant setting) was granted by the FDA in September 2013. Since then, the relevance of neoadjuvant treatment in Her2 overexpressing breast cancer has increased considerably. This for instance has been emphasized by the results of the Neosphere Study, in which dual blockade of Her2 was combined with docetaxel as chemotherapy backbone and resulted in favorable pCR rates.

But it is likely, that anthracyclines could play an important role in enhancing the effectiveness of the above mentioned treatment. However, there is only little data about the cardiac safety of this combination. The use of liposomal doxorubicin might be a valuable alternative with low cardiotoxicity, as it has been shown in comparable publications without the use of pertuzumab. Therefore we report pCR-rate and cardiac safety of a single arm, retrospective, multicenter analysis of neoadjuvant treatment for Her2 positive EBC with liposomal doxorubicin, docetaxel, trastuzumab and pertuzumab.

Methods: In this study 42 women with Her2 positive EBC were investigated in 4 oncological departments in Austria. 41 patients were treated with liposomal doxorubicin (50 mg/m2), docetaxel (75 mg/m2) concurrent with trastuzumab and pertuzumab in standard dosage for 6 cycles as neoadjuvant therapy. One patient refused to receive a chemotherapy but agreed to be treated with combined antibody therapy alone. All patients were free of cardiovascular disease and had a left ventricular ejection fraction (LVEF) of ≥ 50%. Cardiac function was measured by LVEF and was examined at regular intervals (cycles 0-3, cycle 6, FU). Clinical response was evaluated by diagnostic breast imaging after cycles 3 and 6. All patients underwent surgery after neoadjuvant chemotherapy. The absence of any residual invasive cancer in the breast and axilla was defined as pathological complete response (pCR). Median follow up was 1.3 years.

Results: Median age of the patients was 49 years. After 6 cycles of treatment the pCR rate was 76.2%. In this cohort a negative estrogen-and/or progesteron receptor was predictive for pCR (p&lt;0.001). These patients achieved pCR in 95.2%. The antibody only treatment in one case also resulted in a pCR. No patient progressed during treatment. Only one of the patients (2,4%) suffered symptomatic heart failure after surgery. The patient initially presented with an LVEF of 16%.

Conclusions: In this multicenter analysis we observed a considerably high rate of pCR in HER2-positive EBC treated with liposomal doxorubicin, docetaxel, trastuzumab and pertuzumab. Especially the group of hormone receptor negative patients showed a remarkable response rate. The addition of liposomal doxorubicin entails a very favorable cardiotoxicity profile. This regimen is a safe treatment option in patients with HER-2 positive breast cancer.

Citation Format: Egle D, Hubalek M, Hager C, Poyßl C, Lang A, Jäger T, Volgger B, Abdel-Azim S, Tiechl J, Angerer J, Marth C. Efficacy and cardiac safety in neoadjuvant treatment of Her2 positive breast cancer with concomitant nonpegylated liposomal doxorubicin, docetaxel and dual blockade with trastuzumab and pertuzumab: A retrospective analysis. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-14-11.

Effects of ligation of lateral intermuscular septum perforating vessels on blood supply to the femur

INTRODUCTION

With a subvastus approach to the femur, the vessels that perforate the lateral intermuscular septum (LISP-vessels) must be ligated. The effect on the blood supply to the femur remains unclear. The purpose of the current study was to investigate the effect of ligation of the LISP-Vessels on the blood supply and to examine the anatomy of the LISP-vessels and the anastomoses around the femur.

MATERIALS

In six human cadavers the LISP vessels were ligated by a lateral subvastus approach on one side. The contralateral side served as control group. After bilateral injection of different coloured silicon dyes into the lateral and medial circumflex femoral artery (green), deep femoral artery (red) and the superficial femoral artery (blue) dissection was performed bilaterally. The arterial perfusion on both sides was compared and the anatomy of the LISP vessels studied.

RESULTS

The medullary perfusion of the femur was not altered by the ligation of the LISP vessels. It did also not lead to a decrease in periosteal vessel filling. The LISP vessels were shown to be a part of a complex and rich anastomotic network and play an important role in the perfusion of the femur and quadriceps muscle group. The ligature could be compensated for by this anastomotic network. Branches to the periosteum separate from the LISP vessels immediately after perforating the lateral intermuscular septum. The linea aspera turned out to be an important area for the femoral blood supply.

DISCUSSION AND CONCLUSIONS

Exposure of the femur through a lateral subvastus approach with ligation of LISP vessels causes a certain degree of soft tissue trauma. However, by using a gentle surgical technique the periostal perfusion of the femur can be preserved by a potent anastomotic network after ligation of the LISP vessels if they are not ligated to close to the lateral intermuscular septum and the linea aspera is not unnecessarily exposed.

Analysis of right and left ventricular deformation in former world class swimmers: evaluation using speckle tracking

AIM

There is a longstanding debate over the long-term effect of intensive endurance training on cardiac function. Usually, echocardiography has been used as a global evaluation of left ventricular (LV) or right ventricular (RV) function and dimensions. Recently, speckle tracking strain (ST) has provided an analysis of regional RV and LV function. Thus, the intention of the study was to carefully evaluate cardiac function in a group of former world class swimmers applying longitudinal strain (LS) and circumferential strain (CS) analysis.

METHODS

Twelve athletes (45±1.5 years) of a former training group involved in high intensity endurance training were examined 24.9±4.3 years after the end of their active swimming career. An echocardiography was performed and LV function was analyzed based on CS and LS. Also, LS was evaluated for the RV. All measurements were performed for epicardium and endocardium independently.

RESULTS

Mean LV endocardial LS was -20.0±6.3 and epicardial LS -20.2±6.2. LV endocardial CS was -21.3±8.0 and epicardial CS -11.9±4.2. RV endocardial LS had a mean value of -26.4±6.1 and epicardial LS of -28.2±5.6.

CONCLUSION

Twenty-five years after the cessation of endurance training, there was no evidence of a deterioration of RV or LV function as values for RV and LV strain measurements were within normal ranges.

Does joint architecture influence the nature of intra-articular fractures?

INTRODUCTION

The architecture of joints has potentially the greatest influence on the nature of intra-articular fractures. We analysed a large number of intra-articular fractures with two aims: (1) to determine if the pattern of injuries observed supports our conjecture that the local skeletal architecture is an important factor and (2) to investigate whether associated dislocations further affect the fracture pattern.

METHODS

A retrospective study of intra-articular fractures over a 3.5-year period; 1003 joints met inclusion criteria and were analysed. Three independent investigators determined if fractures affected the convex dome, the concave socket, or if both joint surfaces were involved. Further review determined if a joint dislocation occurred with the initial injury. Statistical analysis was performed using a one-way frequency table, and the χ(2) test was used to compare the frequencies of concave and convex surface fractures. The odds ratios (ORs) were calculated to establish the association between the frequencies of concave and convex surface fractures, as well as between dislocation and either fracture surface involvement.

RESULTS

Of the 1003 fractures analysed, 956 (95.3%) involved only the concavity of the joint; in 21 fractures (2.1%) both joint surfaces were involved; and in 26 fractures (2.6%) only the convexity was involved (χ(2)=1654.9, df=2, p<0.0001). As expected, the concavity was 20.8 times more likely to fail than the convexity (11.2-36.6, 95% CI). However, the risk of fracturing the convex surface was 18.6 times higher (9.8-35.2, 95% CI) in association with a simultaneous joint dislocation, compared to those cases without a joint dislocation.

CONCLUSIONS

These results very strongly support the study hypotheses: the skeletal architecture of joints clearly plays a highly significant role in determining the nature of intra-articular fractures. Intra-articular fractures involving the convexity are much more likely to be associated with a concurrent joint dislocation.