THU0055 ANTI-DEGRADATIVE AND PRO-CHONDROGENIC PROPERTIES OF LIRAGLUTIDE, A GLUCAGON-LIKE-PEPTIDE 1 RECEPTOR AGONIST: EVIDENCE FROM PRECLINICAL STUDIES AND IMPLICATION FOR OSTEOARTHRITIS

Background:

Osteoarthritis (OA) is a degenerative joint disease affecting millions of individuals worldwide. Its development has been reported to be associated with cartilage degradation and inflammatory responses leading to pain, swelling and reduced function. Although OA is a disorder of the whole joint, the progressive destruction of cartilage extracellular matrix is considered as its hallmark. To date, approved OA treatments are only symptomatic. Therefore, there is an urgent need to explore disease-modifying OA drugs (DMOADs) that can mitigate, stop, or even reverse the development of OA.

Objectives:

In this context, the objective of this study was to assess the effect of liraglutide, a Glucagon-Like-Peptide 1 Receptor (GLP-1R) agonist approved for type 2 diabetes, on chondrogenesis, catabolism/inflammation and cartilage protection inin vitroandin vivopreclinical models of OA.

Methods:

The capacity of liraglutide to induce chondrogenesis was evaluated using primary human mesenchymal stem cells (hMSCs). Alcian blue staining was used to assess differentiation of hMSC into chondrocyte spheroids. IL-1β-stimulated mouse articular chondrocytes were treated with different concentrations of liraglutide for 24h. Production of matrix metalloproteinase MMP-13, prostaglandin E2 (PGE2) and nitrite was measured by ELISA and Griess reaction, respectively. Exendin 9-39, a GLP-1R antagonist, was used to confirm target engagement in thein vitroexperiments. Intra-articular (IA) injections of liraglutide or vehicle were performed in the type II collagenase rat model. Histopathological analyses (OARSI scores1) were conducted blindly by one investigator.

Results:

Liraglutide induced the differentiation of hMSCs into chondrocytes. Indeed, 21 days after differentiation initiation, 5/6 and 4/6 alcian-blue positive spheroids were observed for 10 and 100nM liraglutide, respectively, versus 0/6 for vehicle. Liraglutide significantly reduced dose-dependently the IL-1β-induced production of PGE2 (5808±178 for vehicle vs 4560±140, 2933±171 and 2365±85 pg/ml for liraglutide 10, 100 and 500nM, respectively, p≤0.001), nitrite (24.9±0.4 for vehicle vs 20.9±1.5, 19.1±0.9 and 16.5±0.5 µM for liraglutide 10, 100 and 500nM, respectively, p≤0.001) and MMP-13 (686±9 for vehicle vs 553±3, 402±5 and 297±8 pg/ml for liraglutide 10, 100 and 500nM, respectively, p≤0.001) in murine chondrocytes. Effects of liraglutide were GLP-1R dependent since exendin 9-39 significantly counteracted both chondrogenesis and inflammation/catabolism markers expression. Histological assessment of rat collagenase-injected knee joint revealed a significant (p≤0.05) decrease of the total joint score in the IA Liraglutide treated group (8±4) compared to vehicle (11±4).

Conclusion:

Liraglutide induced chondrogenesis, decreased metalloproteinase and inflammatory mediators production by chondrocytes and protected cartilage inin vitroandin vivopreclinical OA models, opening the way for repositioning this drug as a potential DMOAD.

References:

[1]Osteoarthritis Cartilage. 2010 Oct;18 Suppl 3:S24-34

Acknowledgments:

All the people who contributed to the InOsteo project: the members of 4P-Pharma, INSERM UMR S938 research team, SATT Lutech and Sorbonne University

Disclosure of Interests:

Francis Berenbaum Grant/research support from: TRB Chemedica (through institution), MSD (through institution), Pfizer (through institution), Consultant of: Novartis, MSD, Pfizer, Lilly, UCB, Abbvie, Roche, Servier, Sanofi-Aventis, Flexion Therapeutics, Expanscience, GSK, Biogen, Nordic, Sandoz, Regeneron, Gilead, Bone Therapeutics, Regulaxis, Peptinov, 4P Pharma, Paid instructor for: Sandoz, Speakers bureau: Novartis, MSD, Pfizer, Lilly, UCB, Abbvie, Roche, Servier, Sanofi-Aventis, Flexion Therapeutics, Expanscience, GSK, Biogen, Nordic, Sandoz, Regeneron, Gilead, Sandoz, Coralie Meurot Employee of: 4P-Pharma, Jerome Breton Employee of: 4P-Pharma, Laure Sudre: None declared, Carole Bougault: None declared, Revital Rattenbach Shareholder of: 4P-Pharma, Employee of: 4P-Pharma, Celine Martin Employee of: 4P-Pharma, Claire Jacques: None declared

P1451Catheter ablation in adults with Wolff-Parkinson-White syndrome: a "real-life" experience

Introduction. Radiofrequency catheter ablation (RFA) is 1st line treatment in symptomatic adult patients with Wolff-Parkinson-White syndrome (WPW). Patients with WPW are often quoted a high success rate for RFA but does this reflect reality? There is a paucity of recent literature and ongoing service developments in the UK may have a negative impact on success by reducing individual operator experience of adult WPW cases (i.e. increasing numbers of cardiac electrophysiologists in each department, patients more likely to undergo RFA as children). In contrast, technological developments (e.g. 3D mapping, steerable sheaths) may have a positive impact on success of RFA in WPW.

Methods. We collected data on all patients with WPW scheduled for 1st time ablation between Jan 2006 and Dec 2018. All patients undergoing re-do RFA during this time were excluded. For comparison, we divided this timeframe into three periods: 2006-9, 2010-13 and 2014-18.

Results. The number of patients scheduled for RFA and the outcome is listed in the Table. The overall success rate was 86.5% and this figure remained constant throughout the 13 year time-frame. Significant complications occurred in 1.17% of cases. 19.9% of patients scheduled for an ablation had no ablation attempted for various reasons (‘safe’ pathway, proximity to AV node etc).

Conclusion. In our centre, the number of adult cases of WPW scheduled for RFA year-on-year remains constant. The complication rate is in line with published literature. The RFA success rate is lower than the published data. As expected, success rate of RFA for WPW varies according to accessory pathway location. 1 in 5 cases scheduled for ablation did not proceed to ablation. This highlights an area where more effective resource planning from the outset can be undertaken.

Table 2006-9 2010-13 2014-18 Patients scheduled for RFA, n 181 152 179 Patients who underwent RFA, n 162 121 127 Overall RFA success rate, % (n) 85.6 (160) 86.6 (119) 87.4 (127) Success rate by AP location, % (n) Free wall Left 91.5 (71) 91.8 (49) 95.3 (64) Right 76.9 (13) 77.8 (9) 60.0 (5) Septal Anterior 77.8 (9) 88.9 (9) 100.0 (4) Mid 75.0 (8) 90.0 (10) 66.7 (3) Posterior 86.0 (57) 82.9 (41) 79.6 (49) RFA success rate in patients with Wolff-Parkinson-White syndrome. AP = accessory pathway, RFA = radiofrequency catheter ablation

OP0083 DORSAL ROOT GANGLIA INFILTRATING MACROPHAGES MAINTAIN OSTEOARTHRITIS PAIN

Background:

Pain is a major debilitating symptom of knee osteoarthritis (OA). However, the extent of joint damage in OA does not correlate well with the severity of pain. The mechanisms that govern OA pain are poorly understood. Immune cells infiltrating nervous tissue may contribute to pain maintenance.

Objectives:

Here we investigated the role of macrophages in the initiation and maintenance of OA pain.

Methods:

Knee joint damage was induced by an unilateral injection of mono-iodoacetate (MIA) or after application of a groove at the femoral condyles of rats fed on high fat diet. Pain-like behaviors were followed over time using von Frey test and dynamic weight bearing. Joint damage was assessed by histology. Dorsal root ganglia (DRG) infiltrating immune cells were assessed over time using flow cytometry. To deplete monocytes and macrophages, Lysmcrex Csfr1-Stop-DTR were injected intrathecal or systemically with diptheria toxin (DT).

Results:

Intraarticular monoiodoacetate injection induced OA and signs of persistent pain, such as mechanical hyperalgesia and deficits in weight bearing. The persisting pain-like behaviors were associated with accumulation of F4/80+macrophages with an M1-like phenotype in the lumbar DRG appearing from 1 week after MIA injection, and that persisted till at least 4 weeks after MIA injection. Macrophages infiltrated DRG were also observed in the rat groove model of OA, 12 weeks after application of a groove at the femoral condyles. Systemic or local depletion of DRG macrophages during established MIA-induced OA completely ablated signs of pain, without affecting MIA-induced knee pathology. Intriguingly when monocytes/macrophages were depleted prior to induction of osteoarthritis, pain-like behaviors still developed, however these pain-like behaviors did not persist over time.In vitro,sensory neurons innervating the affected OA joint programmed macrophages into a M1 phenotype. Local repolarization of M1-like DRG macrophages towards M2 by intrathecal injection of M2 macrophages or anti-inflammatory cytokines resolved persistent OA-induced pain.

Conclusion:

Overall we show that macrophages infiltrate the DRG after knee damage and acquire a M1-like phenotype and maintain pain independent of the lesions in the knee joint. DRG-infiltrating macrophages are not required for induction of OA pain. Reprogramming M1-like DRG-infiltrating macrophages may represent a potential strategy to treat OA pain.

Acknowledgments:

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreements No 814244 and No 642720. Dutch Arthritis Society

Disclosure of Interests:

Ramin Raoof: None declared, Christian Martin: None declared, Huub de Visser: None declared, Judith Prado: None declared, Sabine Versteeg: None declared, Anne Heinemans: None declared, Simon Mastbergen: None declared, Floris Lafeber Shareholder of: Co-founder and shareholder of ArthroSave BV, Niels Eijkelkamp: None declared

Barriers and facilitators to discussing HPV with head and neck cancer patients: A qualitative study using the theoretical domains framework

OBJECTIVE

The incidence of human papillomavirus-associated head and neck cancers (HPV-HNC) is increasing worldwide. Research in other clinical contexts has shown that healthcare professionals (HCPs) can find discussing HPV with patients challenging. However, limited research has been conducted in HNC. This study aimed to investigate barriers and facilitators to, discussing HPV among HCPs caring for patients with HNC in Ireland.

METHODS

Semi-structured telephone/face-to-face interviews were conducted with HCPs. Barriers and facilitators to discussing HPV with patients were identified using the Theoretical Domains Framework (TDF).

RESULTS

20 HCPs (8 clinicians, 3 nurses, 9 allied healthcare professionals) were interviewed. Barriers to discussing HPV included professionals' lack of HPV knowledge, difficulties in talking about sexual issues with patients and lack of privacy to discuss HPV in busy clinic settings. Facilitators included increasing public and patient awareness of the link between HPV and HNC and professional education and skills development.

CONCLUSIONS

This is the first theoretically informed study to identify barriers and facilitators to discussing HPV with HNC patients. HCPs consider HPV discussions to be an essential part of HNC patient care.

PRACTICE IMPLICATIONS

Understanding the issues associated with patient-provider HPV communication will help develop effective interventions to support HCPs in their HPV discussions.

Health resource utilization of labor induction versus expectant management

BACKGROUND

Although induction of labor of low-risk nulliparous women at 39 weeks reduces the risk of cesarean delivery compared with expectant management, concern regarding more frequent use of labor induction remains, given that this intervention historically has been thought to incur greater resource utilization.

OBJECTIVE

The objective of the study was to determine whether planned elective labor induction at 39 weeks among low-risk nulliparous women, compared with expectant management, was associated with differences in health care resource utilization from the time of randomization through 8 weeks postpartum.

STUDY DESIGN

This is a planned secondary analysis of a multicenter randomized trial in which low-risk nulliparous women were assigned to induction of labor at 39 weeks or expectant management. We assessed resource utilization after randomization in 3 time periods: antepartum, delivery admission, and discharge through 8 weeks postpartum.

RESULTS

Of 6096 women with data available, those in the induction of labor group (n = 3059) were significantly less likely in the antepartum period after randomization to have at least 1 ambulatory visit for routine prenatal care (32.4% vs 68.4%), unanticipated care (0.5% vs 2.6%), or urgent care (16.2% vs 44.3%), or at least 1 antepartum hospitalization (0.8% vs 2.2%, P < .001 for all). They also had fewer tests (eg, sonograms, blood tests) and treatments (eg, antibiotics, intravenous hydration) prior to delivery. During the delivery admission, women in the induction of labor group spent a longer time in labor and delivery (median, 0.83 vs 0.57 days), but both women (P = .002) and their neonates (P < .001) had shorter postpartum stays. Women and neonates in both groups had similar frequencies of postpartum urgent care and hospital readmissions (P > .05 for all).

CONCLUSION

Women randomized to induction of labor had longer durations in labor and delivery but significantly fewer antepartum visits, tests, and treatments and shorter maternal and neonatal hospital durations after delivery. These results demonstrate that the health outcome advantages associated with induction of labor are gained without incurring uniformly greater health care resource use.

Combinations of non-invasive indicators to detect dairy cows submitted to high-starch-diet challenge

High-starch diets (HSDs) fed to high-producing ruminants are often responsible for rumen dysfunction and could impair animal health and production. Feeding HSDs are often characterized by transient rumen pH depression, accurate monitoring of which requires costly or invasive methods. Numerous clinical signs can be followed to monitor such diet changes but no specific indicator is able to make a statement at animal level on-farm. The aim of this pilot study was to assess a combination of non-invasive indicators in dairy cows able to monitor a HSD in experimental conditions. A longitudinal study was conducted in 11 primiparous dairy cows fed with two different diets during three successive periods: a 4-week control period (P1) with a low-starch diet (LSD; 13% starch), a 4-week period with an HSD (P2, 35% starch) and a 3-week recovery period (P3) again with the LSD. Animal behaviour was monitored throughout the experiment, and faeces, urine, saliva, milk and blood were sampled simultaneously in each animal at least once a week for analysis. A total of 136 variables were screened by successive statistical approaches including: partial least squares-discriminant analysis, multivariate analysis and mixed-effect models. Finally, 16 indicators were selected as the most representative of a HSD challenge. A generalized linear mixed model analysis was applied to highlight parsimonious combinations of indicators able to identify animals under our experimental conditions. Eighteen models were established and the combination of milk urea nitrogen, blood bicarbonate and feed intake was the best to detect the different periods of the challenge with both 100% of specificity and sensitivity. Other indicators such as the number of drinking acts, fat:protein ratio in milk, urine, and faecal pH, were the most frequently used in the proposed models. Finally, the established models highlight the necessity for animals to have more than 1 week of recovery diet to return to their initial control state after a HSD challenge. This pilot study demonstrates the interest of using combinations of non-invasive indicators to monitor feed changes from a LSD to a HSD to dairy cows in order to improve prevention of rumen dysfunction on-farm. However, the adjustment and robustness of the proposed combinations of indicators need to be challenged using a greater number of animals as well as different acidogenic conditions before being applied on-farm.

A multimodal intervention program to control a long-term Acinetobacter baumannii endemic in a tertiary care hospital

Background

Acinetobacter baumannii causes frequently nosocomial infections worldwide. Its ability to survive on dry surfaces facilitates its spread and the persistence of endemic situations, especially in the intensive care units (ICUs).

The objective of this paper is to describe a multicomponent intervention program designed to control a hyperendemic persistence of multidrug-resistant A. baumannii (MDR-Ab) and to characterize its impact.

Methods

Design: Quasi-experimental intervention study based on open cohorts.

Setting: Public tertiary referral centre. Period: January 2009–August 2017.

Intervention: multifaceted program based on environmental decontamination, hand hygiene, antimicrobial stewardship, contact precautions, active surveillance, weekly reports and regular meetings.

Analysis: joinpoint regression and interrupted time-series analysis.

Results

The intervention was successfully implemented. Through the study period, the compliance with contact precautions changed from 0 to 100% and with hand hygiene, from 41.8 to 82.3%. Between 2012 and 2016, the antibiotic consumption decreased from 165.35 in to 150.44 daily-defined doses/1000 patients-days in the ICU. The incidence density of MDR-Ab in the ICU was 10.9 cases/1000 patients-days at the beginning of the intervention. After this moment, the evolution of the incidence density of MDR-Ab was: between months 0 and 6°, it remained stable; between months 7° and 10°: there was an intense decrease, with an average monthly percentage change (AMPC) = − 30.05%; from 11° month until the end, the decrease was lighter but continuous (AMPC:-2.77%), achieving an incidence density of 0 cases/1000 patients-days on the 18° month, without any new case for 12 months. From the 30° month until the end of the study period, several little outbreaks of MDR-Ab were detected, all of them rapidly controlled. The strains of MDR-Ab isolated during these outbreaks were not clonally related with the previously endemic one, which supports its eradication from the environmental reservoirs.

Conclusion

The multicomponent intervention performed by a multidisciplinary team was effective to eradicate the endemic MDR-Ab.

Reactivation of Plasmodium infection during a treatment with infliximab: A case report

We describe a symptomatic Plasmodium falciparum infection in a 29-year-old Guinean man receiving Infliximab for one year and without recent travel. The reactivation of submicroscopic malaria following the inhibition of TNF-alpha by infliximab is suspected.

Use of P-values and the terms "significant", "non-significant" and "suggestive" in Abstracts in the European Annals of Otorhinolaryngology, Head & Neck Diseases

OBJECTIVES

To evaluate the use of P-values and the terms "significant", "non-significant" and "suggestive" in Abstracts in the European Annals of Otorhinolaryngology, Head & Neck Diseases.

MATERIALS AND METHODS

Consecutive articles accepted for publication during the period January 2016 - February 2019 were systematically reviewed. Main goal: descriptive analysis of the citation of P-values and use of the terms "significant", "non-significant" and "suggestive" in Abstracts. Secondary goal: analytic study of: (i) correlations between citation of a P-value and the main characteristics of authors and topics; and (ii) misuse of the terms "significant", "non-significant" and "suggestive" with respect to cited P-values, and correlations with author and topic characteristics.

RESULTS

In all, 91 articles were included. P-values and the terms "significant", "non-significant" and "suggestive" were cited in 35.1%, 41.7%, 10.9% and 0% of Abstracts, respectively. Citing a P-value did not significantly correlate with author or topic characteristics. There were discrepancies between the terms "non-significant", "significant" and "suggestive" and P-values given in the body of the article in 57.1% of Abstracts, with 30.7% overestimation and 25.2% underestimation of results, without significant correlation with author or topic characteristics.

CONCLUSION

Authors, editors and reviewers must pay particular attention to the spin resulting from inappropriate use of the terms "significant", "non-significant" and "suggestive" in Abstracts of articles submitted to the European Annals of Otorhinolaryngology, Head & Neck Diseases, to improve the rigor, quality and value of the scientific message delivered to the reader.

Blood CD9+ B cell, a biomarker of bronchiolitis obliterans syndrome after lung transplantation

Bronchiolitis obliterans syndrome is the main limitation for long-term survival after lung transplantation. Some specific B cell populations are associated with long-term graft acceptance. We aimed to monitor the B cell profile during early development of bronchiolitis obliterans syndrome after lung transplantation. The B cell longitudinal profile was analyzed in peripheral blood mononuclear cells from patients with bronchiolitis obliterans syndrome and patients who remained stable over 3 years of follow-up. CD24^hi CD38^hi transitional B cells were increased in stable patients only, and reached a peak 24 months after transplantation, whereas they remained unchanged in patients who developed a bronchiolitis obliterans syndrome. These CD24^hi CD38^hi transitional B cells specifically secrete IL-10 and express CD9. Thus, patients with a total CD9⁺ B cell frequency below 6.6% displayed significantly higher incidence of bronchiolitis obliterans syndrome (AUC = 0.836, PPV = 0.75, NPV = 1). These data are the first to associate IL-10-secreting CD24^hi CD38^hi transitional B cells expressing CD9 with better allograft outcome in lung transplant recipients. CD9-expressing B cells appear as a contributor to a favorable environment essential for the maintenance of long-term stable graft function and as a new predictive biomarker of bronchiolitis obliterans syndrome-free survival.

Complete upper airway collapse and apnoea during tethered swimming in horses

BACKGROUND

There is limited knowledge of the breathing strategy and impact on the patency of the upper respiratory tract (URT) in swimming horses.

OBJECTIVES

To describe the respiratory responses and endoscopic appearance of the URT during tethered swimming in horses.

STUDY DESIGN

Prospective descriptive study.

METHODS

Ten race-fit horses, with no history of URT obstruction, were examined during tethered swimming. Endoscopic examination, heart rate, sound recordings and above and below water video recordings were obtained. Plasma lactate concentration was measured before and 5 min after swimming and tracheal endoscopy was performed 30 min after exercise to assess for presence of blood or mucus. Four horses also underwent endoscopy during exercise on the track.

RESULTS

Mean (±s.d.) breathing frequency was 28 ± 5 breaths/min during swimming, with a brief inspiration (mean ± s.d. T_I  = 0.51 ± 0.08 s), followed by a period of apnoea (1.59 ± 0.53 s) and then a short, forced expiration (T_E  = 0.42 ± 0.5 s). During apnoea all horses exhibited complete collapse of the URT including closure of the external nares, nasopharynx and rima glottidis (with bilateral adduction of the arytenoid cartilages and vocal folds) and, in two horses, epiglottic retroversion. No horses had URT collapse during overground exercise. Locomotor-respiratory coupling was not observed during swimming. Median (IQR) plasma lactate post swim was 4.71 mmol/L (2.08-8.09 mmol/L) vs 0.68 mmol/L (0.65-0.71 mmol/L) preswim. Post swim endoscopy revealed grade 1 exercise-induced pulmonary haemorrhage (EIPH) in 2 horses. Median mucus grade was 1 (range 0-3).

MAIN LIMITATIONS

Overground endoscopy was not performed in all horses.

CONCLUSIONS

Horses experienced complete URT collapse associated with post inspiratory apnoea when swimming. The reason for this is unknown but may be to aid buoyancy or associated with the mammalian dive response - a survival reflex to preserve oxygen stores and prevent water entering the lungs.