Clinical and molecular implications of NAB2-STAT6 fusion variants in solitary fibrous tumour

Solitary fibrous tumour (SFT) is a mesenchymal neoplasm characterised by pathognomonic NAB2-STAT6 gene fusions. The clinical implications and prognostic value of different fusion variants has not been clarified. In the current study, we explore the clinicopathological, prognostic and molecular differences between tumours with different fusions. Thirty-nine patients with localised, extrameningeal SFT were included, of whom 20 developed distant recurrence and 19 were without recurrence after long term follow-up. Capture-based RNA sequencing identified 12 breakpoint variants, which were categorised into two groups based on the STAT6 domain composition in the predicted chimeric proteins. Twenty-one of 34 (62%) sequenced tumours had fusions with most of the STAT6 domains intact and were classified as STAT6-Full. Thirteen tumours (38%) contained only the transactivation domain of STAT6 and were classified as STAT6-TAD. Tumours with STAT6-TAD fusions had a higher mitotic count (p=0.016) and were associated with inferior recurrence-free interval (p=0.004) and overall survival (p=0.012). Estimated 10-year recurrence-free survival was 25% for patients with STAT6-TAD tumours compared to 78% for the STAT6-Full group. Distinct transcriptional signatures between the fusion groups were identified, including higher expression of FGF2 in the STAT6-TAD group and IGF2, EGR2, PDGFRB, STAT6 and several extracellular matrix genes in STAT6-Full tumours. In summary, we demonstrate that NAB2-STAT6 fusion variants are associated with distinct clinicopathological and molecular characteristics and have prognostic significance in extrameningeal SFT.

Intranasal delivery of Naloxone-loaded solid lipid nanoparticles as a promising simple and non-invasive approach for the management of opioid overdose

Naloxone is an opioid receptor antagonist that can eradicate all pre-indications of the toxicity and inverse the opioid overdose. However, oral administration of naloxone offers limitations such as its extensive first-pass metabolism that results in poor therapeutic effects. In order to resolve this issue, we developed intranasal solid-lipid nanoparticles in which naloxone was incorporated for the higher brain disposition of naloxone with superior therapeutic effects for the reversal of toxicity of opioid overdose. The preparation of naloxone loaded solid-lipid nanoparticles was done by employing the solvent evaporation method. Later, the designed formulation was optimized by Quality by Design approach, specifically, Box-Behnken method. The composition of optimized formulation was Glyceryl monostearate as a solid lipid (40 mg), Pluronic127 (0.5%) and Tween 80 (0.1%) as a surfactant and co-surfactant, respectively. Furthermore, the characterization of optimized formulation was achieved in terms of particle size, PDI, zeta potential, entrapment efficiency, and drug loading which were 190.2 nm, 0.082, -16 mV, 95 ± 0.532% and 19.08 ± 0.106%, respectively. Afterwards, in vitro, ex vivo and in vivo experiments were performed in which higher drug release and superior drug uptake by nasal membrane were observed for naloxone-loaded solid-lipid nanoparticles, later it was confirmed by confocal microscopy of ex vivo nasal membrane tissue. The findings of gamma scintigraphy investigation exhibited better deposition of naloxone-loaded solid-lipid nanoparticles as compared to naloxone solution. Also, the better deposition of naloxone by gamma scintigraphy was further validated by the investigation through the biodistribution study. Additionally, the key findings of the pharmacokinetic study revealed C_max, T_max, AUC_0-t, AUC_0-∞, T_1/2 and K_e was found to be 163.95 ± 2.64 ng/ml, 240 ± 2.1 min, 17.75 ± 1.08 ng.hr/ml, 18.82 ± 2.51 ng.hr/ml, 70.71 ± 0.115 min, 0.098 ± 0.01 h^-1 respectively. Lastly, investigations such as weight variation and histopathological proved the plausible potential of naloxone-loaded solid-lipid nanoparticles in terms of safety as no toxicity was noticed even after the administration of the three-folds dose of the normal dose. Therefore, considering all these findings, it could be easy to say that these developed naloxone-loaded solid-lipid nanoparticles could be administrated via intranasal route and can act as successful novel nanoformulation for the effective treatment of opioid overdose.

Intranasal solid lipid nanoparticles for management of pain: A full factorial design approach, characterization & Gamma Scintigraphy

Pain is a noxious stimulus caused due to tissue damage and varies from mild to severe. Nalbuphine (NLB) is an approved, inexpensive, non-controlled, opioid agonist/antagonist analgesic used worldwide in various clinical settings for pain management. The current study aims to formulate NLB loaded solid lipid nanoparticles (SLNs) using solvent injection technology. The morphological and chemical structure of the developed SLNs were characterized using Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM) and Fourier Transformation Infrared Spectroscopy (FTIR). The results revealed from the point prediction confirmation in design expert software was the formulation of NLB-SLNs with an average particle size of (170.07 ± 25.1 nm), encapsulation efficiency (93.6 ± 1.5%) & loading capacity of 26.67%. The in-vitro permeation of developed NLB-SLNs was observed to be 94.18% at 8 h when compared with NLB solution whose maximum permeation was seen within 3 h of application. Efficacy of the formulation was also evaluated using eddy's hot plate method, where the onset of action started within 10 min of administration, and the maximum effect was observed at 1 h. The NLB-SLNs was screened for cytotoxicity in human embryonic kidney cells (HEK-293), and the dosage was considered safe when administered intranasally in animal since no detectable effect to the brain was observed. Biodistribution and gamma scintigraphy study of NLB-SLNs showed the prepared formulation reaching the target site, i.e. brain and was retained. Conclusively, the prepared NLB-SLNs formulation was safe and effective in producing an analgesic effect in vivo.

Combination of Ginsenosides Rb2 and Rg3 Promotes Angiogenic Phenotype of Human Endothelial Cells via PI3K/Akt and MAPK/ERK Pathways

Shexiang Baoxin Pill (SBP) is an oral formulation of Chinese materia medica for the treatment of angina pectoris. It displays pleiotropic roles in protecting the cardiovascular system. However, the mode of action of SBP in promoting angiogenesis, and in particular the synergy between its constituents is currently not fully understood. The combination of ginsenosides Rb2 and Rg3 were studied in human umbilical vein endothelial cells (HUVECs) for their proangiogenic effects. To understand the mode of action of the combination in more mechanistic detail, RNA-Seq analysis was conducted, and differentially expressed genes (DEGs), pathway analysis and Weighted Gene Correlation Network Analysis (WGCNA) were applied to further identify important genes that a play pivotal role in the combination treatment. The effects of pathway-specific inhibitors were observed to provide further support for the hypothesized mode of action of the combination. Ginsenosides Rb2 and Rg3 synergistically promoted HUVEC proliferation and tube formation under defined culture conditions. Also, the combination of Rb2/Rg3 rescued cells from homocysteine-induced damage. mRNA expression of CXCL8, CYR61, FGF16 and FGFRL1 was significantly elevated by the Rb2/Rg3 treatment, and representative signaling pathways induced by these genes were found. The increase of protein levels of phosphorylated-Akt and ERK42/44 by the Rb2/Rg3 combination supports the notion that it promotes endothelial cell proliferation via the PI3K/Akt and MAPK/ERK signaling pathways. The present study provides the hypothesis that SBP, via ginsenosides Rb2 and Rg3, involves the CXCR1/2 CXCL8 (IL8)-mediated PI3K/Akt and MAPK/ERK signaling pathways in achieving its proangiogenic effects.

Optimisation of Flight and Maintenance Planning for Defence Aviation with Modified Artificial Bee Colony Algorithm

The planning of flight operations and maintenance is a crucial activity for both commercial and military aircraft. Military aircraft have to be always mission-ready. The task of ensuring this can become quite challenging when several operational requirements and maintenance constraints are to be fulfilled simultaneously. This paper, therefore, addresses the optimisation of flight and maintenance planning (FMP) when several diverse factors such as aircraft flying hours (AFH), flight cycles (FC), calendar life, annual flying requirement (AFR), etc. are to be factored in. Such a problem has not been considered previously. Because the problem can become unwieldy to solve by other methods, two schemes, that is, the genetic algorithm (GA) and modified artificial bee colony (ABC) algorithm for constrained optimisation have been utilised. The objective is to maximise the utilisation rate (UR) of aircraft, while also satisfying other operational and maintenance constraints. The algorithm is tested on a fleet of eight aircraft. In addition to a one-year planning period, a planning horizon of ten years has also been simulated. The results show that both the GA and modified ABC algorithm can be effectively used to solve the FMP problem.

The NeST (Neoadjuvant systemic therapy in breast cancer) study: National Practice Questionnaire of United Kingdom multi-disciplinary decision making

BACKGROUND

Neoadjuvant systemic therapy (NST) is increasingly used in the treatment of breast cancer, yet it is clear that there is significant geographical variation in its use in the UK. This study aimed to examine stated practice across UK breast units, in terms of indications for use, radiological monitoring, pathological reporting of treatment response, and post-treatment surgical management.

METHODS

Multidisciplinary teams (MDTs) from all UK breast units were invited to participate in the NeST study. A detailed questionnaire assessing current stated practice was distributed to all participating units in December 2017 and data collated securely usingREDCap. Descriptive statistics were calculated for each questionnaire item.

RESULTS

Thirty-nine MDTs from a diverse range of hospitals responded. All MDTs routinely offered neoadjuvant chemotherapy (NACT) to a median of 10% (range 5-60%) of patients. Neoadjuvant endocrine therapy (NET) was offered to a median of 4% (range 0-25%) of patients by 66% of MDTs. The principal indication given for use of neoadjuvant therapy was for surgical downstaging. There was no consensus on methods of radiological monitoring of response, and a wide variety of pathological reporting systems were used to assess tumour response. Twenty-five percent of centres reported resecting the original tumour footprint, irrespective of clinical/radiological response. Radiologically negative axillae at diagnosis routinely had post-NACT or post-NET sentinel lymph node biopsy (SLNB) in 73.0 and 84% of centres respectively, whereas 16% performed SLNB pre-NACT. Positive axillae at diagnosis would receive axillary node clearance at 60% of centres, regardless of response to NACT.

DISCUSSION

There is wide variation in the stated use of neoadjuvant systemic therapy across the UK, with general low usage of NET. Surgical downstaging remains the most common indication of the use of NAC, although not all centres leverage the benefits of NAC for de-escalating surgery to the breast and/or axilla. There is a need for agreed multidisciplinary guidance for optimising selection and management of patients for NST. These findings will be corroborated in phase II of the NeST study which is a national collaborative prospective audit of NST utilisation and clinical outcomes.

Palmar psoriasis or missed BCC?-A case report

Case report

A 76-year-old Caucasian woman with a history of previous BCCs excised from the head and legs was referred from the dermatology team with a biopsy proven superficial BCC to the left palm. The patient had presented to the dermatology team with the same lesion 7 years prior to the definitive diagnosis. The lesion was described as 27 × 15 mm scaly, poorly-defined, plaque-like lesion to the central palm. There was no ulceration or visible telangiectasia. At the time, an initial diagnosis of psoriasis was given and she received several courses of topical treatments to no avail. Eventually, a biopsy was taken which revealed a multifocal superficial BCC. After unsuccessful attempts at treating with topical Imiquimod, the lesion was surgically excised and resurfaced with a full thickness skin graft.

Discussion

The current understanding that BCCs derive from cells of the hair follicle cannot explain their appearance on the palm. Alternative hypotheses have been proposed as to their actual origin which would account for this rare occurrence. Ultimately, histology can determine the nature of the lesion. We urge clinicians encountering atypical, non-healing lesions to glabrous skin to keep in mind a diagnosis of skin cancer as a delayed diagnosis can lead to increased morbidity.

Comparative Evaluation of Chemo-mechanical and Rotary-mechanical Methods in Removal of Caries with Respect to Time Consumption and Pain Perception in Pediatrc Dental Patients

Aim and objective

Materials and methods

The Carisolv system for caries removal, consisting of a solvent gel and a specially designed hand instrument, as compared to the conventional method of caries removal, i.e., Airotor. Sixty patients in the age-group of 6–14 years, having Black's class I dentinal caries with the cavity in the molars, were enrolled for the study.

Results

The time for caries removal with Carisolv and Airotor was, respectively, 7.17 ± 1.57 and 8.00 ± 1.56 minutes. Thus, the mean time taken was also significantly higher in group II as compared to group I (t = 4.805; p < 0.001).

How to cite this article

Katiyar A, Gupta S, Gupta K, et al. Comparative Evaluation of Chemo-mechanical and Rotary-mechanical Methods in Removal of Caries with Respect to Time Consumption and Pain Perception in Pediatrc Dental Patients. Int J Clin Pediatr Dent 2021;14(1):115–119.

Bio-signal data sharing security through watermarking: a technical survey

Due to smart healthcare systems highly connected information and communications technologies, sensitive medical information and records are easily transmitted over the networks. However, stealing of healthcare data is increasing crime every day to greatly impact on financial loss. In order to this, researchers are developing various cost-effective bio-signal based data hiding techniques for smart healthcare applications. In this paper, we first introduce various aspects of data hiding along with major properties, generic embedding and extraction process, and recent applications. This survey provides a comprehensive survey on data hiding techniques, and their new trends for solving new challenges in real-world applications. Then, we survey the various notable bio-signal based data hiding techniques. The summary of some notable techniques in terms of their objective, type of data hiding, methodology and database used, performance metrics, important features, and limitations are also presented in tabular form. At the end, we discuss the major issues and research directions to explore the promising areas for future research.

Terbinafine resistance in dermatophytes: Time to revisit alternate antifungal therapy

Resistant superficial dermatophytic infections of the skin and its appendages have emerged as a major health problem in India. Mutations in Squalene epoxidase gene have led to increasing incidence of resistance to terbinafine in dermatophytic isolates. We examined six patients with recalcitrant dermatophytosis attending Dermatology OPD at a tertiary care hospital and demonstrated terbinafine resistance by molecular method. Immediate hyperitivity (IH) reaction to Trichophytin antigen was highlighted in these patients. The patients were treated with alternate antifungals after demonstration of resistance to terbinafine based on the antifungal susceptibility testing (AFST). On follow up the patients responded well to the substitute but the duration of therapy had to be prolonged beyond six weeks.

Dysphagia presentation and management following COVID-19: an acute care tertiary centre experience

OBJECTIVES

As the pathophysiology of COVID-19 emerges, this paper describes dysphagia as a sequela of the disease, including its diagnosis and management, hypothesised causes, symptomatology in relation to viral progression, and concurrent variables such as intubation, tracheostomy and delirium, at a tertiary UK hospital.

RESULTS

During the first wave of the COVID-19 pandemic, 208 out of 736 patients (28.9 per cent) admitted to our institution with SARS-CoV-2 were referred for swallow assessment. Of the 208 patients, 102 were admitted to the intensive treatment unit for mechanical ventilation support, of which 82 were tracheostomised. The majority of patients regained near normal swallow function prior to discharge, regardless of intubation duration or tracheostomy status.

CONCLUSION

Dysphagia is prevalent in patients admitted either to the intensive treatment unit or the ward with COVID-19 related respiratory issues. This paper describes the crucial role of intensive swallow rehabilitation to manage dysphagia associated with this disease, including therapeutic respiratory weaning for those with a tracheostomy.

Organophosphate induced delayed neuropathy after an acute cholinergic crisis in self-poisoning

INTRODUCTION

Despite organophosphate pesticide is the most prevalent cause of acute poisoning in low- and middle-income countries, data on organophosphate induced delayed neuropathy (OPIDN) are limited. We aimed to characterize organophosphates' long-term effects on the peripheral nervous system after an acute cholinergic crisis in adults.

METHODS

We performed a prospective observational study in an academic hospital of north India in patients aged 13-40 years with acute organophosphate ingestion. After resolving the cholinergic crisis, the patients were followed for six months with neurologic assessments, including history, neurologic examination, and nerve conduction study (NCS).

RESULTS

Twenty-three patients were recruited to the study. All but one had normal neurological examination and NCS at discharge from hospital a median duration of six days (interquartile range, 3-10) after self-poisoning. Eight (34.8%) developed OPIDN during the six-month follow-up. Three patients had symptomatic neuropathy, and NCS detected subclinical peripheral nerve involvement in five. All cases were associated with chlorpyrifos ingestion (8/17 total chlorpyrifos cases). Two OPIDN cases had foot drop and gait ataxia at three-month which persist at six-month. One patient had distal paresthesia at three months, which improved at a six-month follow-up. NCS in OPIDN cases invariably revealed axonal degeneration, injury to motor fibers more than sensory fibers, and frequent peroneal nerve involvement. None of the baseline characteristics, including the ingested amount, predicted clinical or subclinical OPIDN in chlorpyrifos self-poisoned patients on a univariant analysis.

CONCLUSION

Peripheral nerve involvement is not uncommon after recovery from a cholinergic crisis in chlorpyrifos self-poisoning and debilitating in some patients. Detection of subclinical injury on NCS may provide an early window to prevent severe symptomatic neuropathy.

Measurement of the Low-Energy Antideuteron Inelastic Cross Section

In this Letter, we report the first measurement of the inelastic cross section for antideuteron-nucleus interactions at low particle momenta, covering a range of 0.3≤p<4  GeV/c. The measurement is carried out using p-Pb collisions at a center-of-mass energy per nucleon-nucleon pair of sqrt[s_{NN}]=5.02  TeV, recorded with the ALICE detector at the CERN LHC and utilizing the detector material as an absorber for antideuterons and antiprotons. The extracted raw primary antiparticle-to-particle ratios are compared to the results from detailed ALICE simulations based on the geant4 toolkit for the propagation of (anti)particles through the detector material. The analysis of the raw primary (anti)proton spectra serves as a benchmark for this study, since their hadronic interaction cross sections are well constrained experimentally. The first measurement of the inelastic cross section for antideuteron-nucleus interactions averaged over the ALICE detector material with atomic mass numbers ⟨A⟩=17.4 and 31.8 is obtained. The measured inelastic cross section points to a possible excess with respect to the Glauber model parametrization used in geant4 in the lowest momentum interval of 0.3≤p<0.47  GeV/c up to a factor 2.1. This result is relevant for the understanding of antimatter propagation and the contributions to antinuclei production from cosmic ray interactions within the interstellar medium. In addition, the momentum range covered by this measurement is of particular importance to evaluate signal predictions for indirect dark-matter searches.

Developing a Data Integrated COVID-19 Tracking System for Decision-Making and Public Use

Introduction

The unprecedented COVID-19 pandemic unveiled a strong need for advanced and informative surveillance tools. The Centre for Health Informatics (CHI) at the University of Calgary took action to develop a surveillance dashboard, which would facilitate the education of the public, and answer critical questions posed by local and national government.

Objectives

The objective of this study was to create an interactive method of surveillance, or a “COVID-19 Tracker” for Canadian use. The Tracker offers user-friendly graphics characterizing various aspects of the current pandemic (e.g. case count, testing, hospitalizations, and policy interventions).

Methods

Six publicly available data sources were used, and were selected based on the frequency of updates, accuracy and types of data, and data presentation. The datasets have different levels of granularity for different provinces, which limits the information that we are able to show. Additionally, some datasets have missing entries, for which the “last observation carried forward” method was used. The website was created and hosted online, with a backend server, which is updated on a daily basis. The Tracker development followed an iterative process, as new figures were added to meet the changing needs of policy-makers.

Results

The resulting Tracker is a dashboard that visualizes real-time data, along with policy interventions from various countries, via user-friendly graphs with a hover option that reveals detailed information. The interactive features allow the user to customize the figures by jurisdiction, country/region, and the type of data shown. Data is displayed at the national and provincial level, as well as by health regions.

Conclusion

The COVID-19 Tracker offers real-time, detailed, and interactive visualizations that have the potential to shape crucial decision-making and inform Albertans and Canadians of the current pandemic.

Role of vacuum assisted excision in minimising overtreatment of ductal atypias

PURPOSE

B3 lesions are indeterminate lesions of uncertain malignant potential. They include lesions with and without epithelial atypia. Those with atypia include atypical intraductal epithelial proliferation (AIDEP)/atypical ductal hyperplasia (ADH) and flat epithelial atypia (FEA). They are traditionally managed with surgery. Vacuum assisted excision (VAE) allows larger samples to be obtained using a vacuum assisted biopsy (VAB) device, which equates to a surgical biopsy. We propose that VAE and mammographic surveillance is a safe alternative to surgery in managing the ductal atypias; (AIDEP/ADH and FEA).

METHOD

Retrospective analysis of prospectively collected data on B3 lesions (April 2009 - March 2016) from consecutive breast screening patients diagnosed with AIDEP/ADH or FEA on initial diagnostic core biopsy. Mammographic abnormality, breast density, size, management pathway and upgrade to cancer and types of cancer were also collected during the treatment pathway and 5 year surveillance period (April 2009 - April 2019).

RESULTS

273 cases of ductal atypia were identified. 187/273 (68.5 %) cases were managed with VAE only as no upgrade to malignancy and then 5 year mammographic surveillance. 34/273 (12.5 %) cases had a VAE diagnosing malignancy. 24/273 (8.8 %) cases had a VAE and then a surgical biopsy due to radiological or pathological concern, 8/24 upgraded to malignancy. 22/273 (8%) cases had a surgical diagnostic biopsy, 9/22 (41 %) cases were upgraded to malignancy. In total 51/273 (19 %) cases were diagnosed with cancer on the new pathway (13 invasive (all ER positive and Her2 negative) and 38 non-invasive, (34 ductal carcinoma in situ (DCIS) and 4 cases of lobular carcinoma in situ (LCIS)). While 17/273 (6.2 %) cases developed malignancy (12 invasive (all HER2 negative) and 4 DCIS and 1 LCIS) during the 5 year surveillance period.

CONCLUSIONS

VAE is a safe alternative to surgery in managing ductal atypias. 187/273 (68.5 %) women avoided surgery. While 34/51 cancers (66.7 %) were diagnosed preoperatively using VAE, allowing the women to have a single therapeutic procedure.

Submental nalbuphine exhibits improved efficacy in ameliorating acute pain in prehospital emergent conditions; a comparative study with conventional intramuscular using gamma scintigraphy

BACKGROUND

Nalbuphine (NLB) is a kappa-agonist and mu-partial antagonist, widely used for opioid withdrawal de-addiction, opioid-induced pruritis and as emergent analgesia.

OBJECTIVE

The present study aimed to assess the safety and efficacy of NLB in pain sensitization, through a submental route so as to provide faster management in emergent situations.

MATERIALS & METHODS

In-vivo efficacy and safety studies of NLB-submental injection were assessed in Sprague-Dawley(SD) rats. For eddy's hot plate study, animals were allocated into three groups, the first group served as normal control; group II received NLB (through submental route at 1.2 mg/kg); group III received NLB (through intramuscular route at 1.2 mg/kg). Response latency (in terms of response latency) was measured at 10, 30 & 60 min in all the experimental groups. Safety studies were carried out according to OECD 423. In-vitro release study was conducted using a cellulose dialysis membrane (12,000 KDa). The biodistribution and release kinetics studies were carried out using gamma scintigraphy studies in New Zealand rabbits and humans respectively.

RESULTS

The response latency of NLB from the submental route was found to be 7.17 (SD 1.47) seconds and in the case of the intramuscular route it was calculated as 4.00 (SD 1.26) seconds at 10 min. The data depicts the better efficacy of submental injection in ameliorating pain than the intramuscular injection. Toxicity studies predict the safe profile through a submental route. The release kinetics in humans of submental NLB was 46% faster as compared to the intramuscular site of injection. The NLB injection through both routes was compared by non-invasive gamma scintigraphy technique and we found that submental injection has faster (within 10 min) onset of action & distributes rapidly.

CONCLUSION

The submental route of NLB is faster, more efficacious than the intramuscular route. Thus, we conclude that in the case of emergent scenarios (i.v or i.m. route is compromised), where immediate relief is necessary, the submental route is a preferred choice.

Efficacy of Single Transverse Neck Incision for Modified Radical Neck Dissection

Background

To assess the viability of the single transverse neck incision (STNI) for modified radical neck dissection and to analyze the yield of lymph nodes using this approach.

Materials and Methods

We conducted a prospective observational study in the Department of Head and Neck Surgical Oncology at our Tertiary Cancer Care Centre from November 2013 to May 2017.

Results

A total of 257 patients underwent surgical treatment for malignant tumors of the head and neck which included 265 modified radical neck dissections (eight bilateral and 249 unilateral). Average of total dissected nodal yield was 37.07. Average yield of positive neck nodes was 2.78.

Conclusion

Single transverse neck incision is an acceptable technique for modified radical neck dissection as it provides adequate surgical exposure for achieving optimal nodal clearance with little technical difficulty.

Small molecule inhibitors possibly targeting the rearrangement of Zika virus envelope protein

The recurrent public health threat imposed by Zika Virus (ZIKV) in various geographical areas necessitates the immediate development of antiviral compounds or vaccines. Flaviviral Envelope (E) proteins are essential for host-cell recognition and virion entry. Consequently, they represent an important target for antiviral therapy, with the aim of preventing viral spread during early stages of infection. Due to conformational rearrangement during entry, flavivirus E proteins present several alternative conformations as potential antiviral targets - for blocking entry or virus-host membrane fusion. We previously identified a conserved hydrophobic region, between DI/DIII of ZIKV E protein, with potential to act as an antiviral target. Here, we screened commercially available antiviral compound libraries against ZIKV E protein, using a structure-based drug discovery approach. The antiviral efficacy of the top ten screened compounds were experimentally validated for inhibition of ZIKV replication in Vero Cells. Compound F1065-0358 was observed to inhibit ZIKV replication with an IC50 of 14.0 μM. Ligand-protein complex molecular dynamic simulations confirmed the stability of ligand binding up to 100 ns. Together, results from this study indicate that F1065-0358 functions as a ZIKV virus inhibitor by interfering E protein conformational rearrangement. Furthermore, given that F1065-0358 interacts with highly conserved residues of E protein, this raises the potential for its efficacy against other pathogenic flaviviruses.

Evaluation of Non-Invasive Ankle Joint Effort Prediction Methods for Use in Neurorehabilitation Using Electromyography and Ultrasound Imaging

OBJECTIVE

Reliable measurement of voluntary human effort is essential for effective and safe interaction between the wearer and an assistive robot. Existing voluntary effort prediction methods that use surface electromyography (sEMG) are susceptible to prediction inaccuracies due to non-selectivity in measuring muscle responses. This technical challenge motivates an investigation into alternative non-invasive effort prediction methods that directly visualize the muscle response and improve effort prediction accuracy. The paper is a comparative study of ultrasound imaging (US)-derived neuromuscular signals and sEMG signals for their use in predicting isometric ankle dorsiflexion moment. Furthermore, the study evaluates the prediction accuracy of model-based and model-free voluntary effort prediction approaches that use these signals.

METHODS

The study evaluates sEMG signals and three US imaging-derived signals: pennation angle, muscle fascicle length, and echogenicity and three voluntary effort prediction methods: linear regression (LR), feedforward neural network (FFNN), and Hill-type neuromuscular model (HNM).

RESULTS

In all the prediction methods, pennation angle and fascicle length significantly improve the prediction accuracy of dorsiflexion moment, when compared to echogenicity. Also, compared to LR, both FFNN and HNM improve dorsiflexion moment prediction accuracy.

CONCLUSION

The findings indicate FFNN or HNM approach and using pennation angle or fascicle length predict human ankle movement intent with higher accuracy.

SIGNIFICANCE

The accurate ankle effort prediction will pave the path to safe and reliable robotic assistance in patients with drop foot.

Enhancement in brain uptake of vitamin D3 nanoemulsion for treatment of cerebral ischemia: formulation, gamma scintigraphy and efficacy study in transient middle cerebral artery occlusion rat models

AIM

For the treatment of cerebral ischaemia, vitamin-D₃ loaded nanoemulsions were developed.

METHOD

Tween 20 and polyethylene glycol were chosen as surfactant/co-surfactant, while oleic acid as the oil phase. The formulation was characterised for various in-vitro parameters. Targeting efficiency was investigated through radiometry, gamma scintigraphy and efficacy was studied in transient middle cerebral artery occlusion (MCAo) rat model.

RESULT

Vitamin D₃-nanoemulsion showed a mean size range of 49.29 ± 10.28 nm with polydispersity index 0.17 ± 0.04 and zeta potential 13.77 mV. The formulation was found stable during thermodynamic stability study and permeated within 180 min through sheep nasal mucosa (permeation coefficient 7.873 ± 0.884 cm/h). Gamma scintigraphy and radiometry assay confirmed better percentage deposition (2.53 ± 0.17%) of ^99mTc-vitamin D₃-nanoemulsion through nasal route compared to IV administered ^99mTc-vitamin D₃ solution (0.79 ± 0.03%). Magnetic Resonance Imaging (MRI) of the ischaemic model confirmed better efficacy of vitamin D₃-nanoemulsion.

CONCLUSION

This work demonstrated better permeation, deposition, and efficacy of vitaminD₃-nanoemulsion through the intranasal route.

Polysaccharides like pentagalloylglucose, parishin a and stevioside inhibits the viral entry by binding the Zika virus envelope protein

ZIKV belongs to a flavivirus family in which class II fusion proteins involve a low pH-dependent membrane fusion leading to infection of host cells. Envelope (E) protein is primarily responsible for the viral host membrane fusion and is the major target for inhibiting viral entry. Our findings reveal that compounds like PGG, Parishin A, and Stevioside have shown a high affinity for E protein and found to be active against various other viral infections. The binding of these molecules to E protein was found to decrease the RMSD and RMSF values of the ligand protein complex and restricted the Radius of Gyration in molecular dynamics simulation analysis. Further, the binding free energy calculations suggested the stability of complexes throughout simulations trajectory that could reduce the flexibility of the linker so as to block the folding back event of membrane fusion. A recent study has shown that PGG inhibits the early stages of viral entry in HCV and ZIKV. Therefore, we propose that PGG inhibits the entry of virion via binding the E protein and restricting the conformational rearrangement during membrane fusion.Communicated by Ramaswamy H. Sarma.

Probing the Effects of Strong Electromagnetic Fields with Charge-Dependent Directed Flow in Pb-Pb Collisions at the LHC

The first measurement at the LHC of charge-dependent directed flow (v_{1}) relative to the spectator plane is presented for Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV. Results are reported for charged hadrons and D^{0} mesons for the transverse momentum intervals p_{T}>0.2  GeV/c and 3<p_{T}<6  GeV/c in the 5%-40% and 10%-40% centrality classes, respectively. The difference between the positively and negatively charged hadron v_{1} has a positive slope as a function of pseudorapidity η, dΔv_{1}/dη=[1.68±0.49(stat)±0.41(syst)]×10^{-4}. The same measurement for D^{0} and D[over ¯]^{0} mesons yields a positive value dΔv_{1}/dη=[4.9±1.7(stat)±0.6(syst)]×10^{-1}, which is about 3 orders of magnitude larger than the one of the charged hadrons. These measurements can provide new insights into the effects of the strong electromagnetic field and the initial tilt of matter created in noncentral heavy ion collisions on the dynamics of light (u, d, and s) and heavy (c) quarks. The large difference between the observed Δv_{1} of charged hadrons and D^{0} mesons may reflect different sensitivity of the charm and light quarks to the early time dynamics of a heavy ion collision. These observations challenge some recent theoretical calculations, which predicted a negative and an order of magnitude smaller value of dΔv_{1}/dη for both light flavor and charmed hadrons.

Filgrastim loading in PLGA and SLN nanoparticulate system: a bioinformatics approach

OBJECTIVE

In this research work, we hypothesized to predict the nanoparticulate system, best suited for targeted delivery of filgrastim. Significance: Targeted delivery of filgrastim to bone marrow is required to decrease the incidence of neutropenia/febrile neutropenia. This is achieved by nanoparticulate systems, duly designed by bioinformatics approach.

METHOD

The targeted delivery of filgrastim in nanoparticulate system was achieved by molecular dynamics (MD) simulation studies. Two matrices comprising PLGA and SLN (tripalmitin, core component of SLN system) were modeled separately with proposed drug filgrastim. Energy minimization of all systems was done using the steepest descent method. PLGA and tripalmitin systems were equalized at 310 °C, at 1 bar pressure with Berendsen barostat for 200 ps using a v-rescale thermostat for 100 ps. Atomistic MD simulations of four model system and mass density of interacting systems were calculated.

RESULTS

The mass density maps of each nanoparticle system, that is, PLGA and tripalmitin showed an increase in density toward the end of the simulation. The contact numbers attained equilibria with the average number of approx.. 1500 contacts in case of tripalmitin-filgrastim system. While PLGA-filgrastim system shows lesser contacts as compared to tripalmitin with average contacts of approx. 1000.The binding free energy was predicted to be -1104 kJ/mol in tripalmitin-filgrastim complex and -421 kJ/mol in PLGA-filgrastim system.

CONCLUSION

Findings of study revealed that both nanoparticle systems assumed to be good model for drug-carrier systems. Though SLN systems were thought to be more appropriate than PLGA, still the in vivo findings could ascertain this hypothesis in futuristic work.

Evidence of Spin-Orbital Angular Momentum Interactions in Relativistic Heavy-Ion Collisions

The first evidence of spin alignment of vector mesons (K^{*0} and ϕ) in heavy-ion collisions at the Large Hadron Collider (LHC) is reported. The spin density matrix element ρ_{00} is measured at midrapidity (|y|<0.5) in Pb-Pb collisions at a center-of-mass energy (sqrt[s_{NN}]) of 2.76 TeV with the ALICE detector. ρ_{00} values are found to be less than 1/3 (1/3 implies no spin alignment) at low transverse momentum (p_{T}<2  GeV/c) for K^{*0} and ϕ at a level of 3σ and 2σ, respectively. No significant spin alignment is observed for the K_{S}^{0} meson (spin=0) in Pb-Pb collisions and for the vector mesons in pp collisions. The measured spin alignment is unexpectedly large but qualitatively consistent with the expectation from models which attribute it to a polarization of quarks in the presence of angular momentum in heavy-ion collisions and a subsequent hadronization by the process of recombination.

Japanese encephalitis virus - exploring the dark proteome and disorder-function paradigm

Japanese encephalitis virus (JEV) is one of the major causes of viral encephalitis all around the globe. Approximately 3 billion people in endemic areas are at risk of Japanese encephalitis. To develop a wholistic understanding of the viral proteome, it is important to investigate both its ordered and disordered proteins. However, the functional and structural significance of disordered regions in the JEV proteome has not been systematically investigated as of yet. To fill this gap, we used here a set of bioinformatics tools to analyze the JEV proteome for the predisposition of its proteins for intrinsic disorder and for the presence of the disorder-based binding regions (also known as molecular recognition features, MoRFs). We also analyzed all JEV proteins for the presence of the probable nucleic acid-binding (DNA and RNA) sites. The results of these computational studies are experimentally validated using JEV capsid protein as an illustrative example. In agreement with bioinformatic analysis, we found that the N-terminal region of the JEV capsid (residues 1-30) is intrinsically disordered. We showed that this region is characterized by the temperature response typical for highly disordered proteins. Furthermore, we have experimentally shown that this disordered N-terminal domain of a capsid protein has a noticeable 'gain-of-structure' potential. In addition, using DOPS liposomes, we demonstrated the presence of pronounced membrane-mediated conformational changes in the N-terminal region of JEV capsid. In our view, this disorder-centric analysis would be helpful for a better understanding of the JEV pathogenesis.

A Phase 3, Randomised, Open-Label, Non-inferiority Trial Evaluating Anti-Rabies Monoclonal Antibody Cocktail (TwinrabTM) Against Human Rabies Immunoglobulin (HRIG)

BACKGROUND

Limited supply, cost and potential for severe adverse effects observed with the blood derived rabies immunoglobulin products has led to search for alternative therapies. This issue has been addressed by developing an antirabies monoclonal antibody cocktail.

METHODS

This is a phase 3, randomized, open-label, noninferiority trial conducted in patients with WHO category III exposure with suspected rabid animal. Eligible patients were assigned to either the test arm, TwinrabTM (docaravimab and miromavimab) or the reference arm, Human rabies immunoglobulin (HRIG; Imogam® Rabies-HT), in a ratio of 1:1. The primary endpoint was the comparison of responder rates between the two arms assessed as percentage of those with rabies virus neutralizing antibodies titers ≥ 0.5 IU/mL on day 14.

RESULTS

A total of 308 patients were equally randomized into the two arms. In the per-protocol (PP) population, there were 90.21% responders in the TwinrabTM arm and, 94.37% in the HRIG arm. The Geometric Mean of RFFIT titres in the PP on day 14 were 4.38 and 4.85 IU/mL, for the TwinrabTM and HRIG arms, respectively. There were no deaths or serious adverse events reported.

CONCLUSIONS

This study confirmed that TwinrabTM is non-inferior to HRIG in terms of providing an unbroken window of protection up to day 84. This trial in healthy adults with WHO category III exposure from suspected rabid animal also establishes the safety of TwinrabTM in patients with one WHO approved vaccine regimen (Essen).

TRIALS REGISTRATION

CTRI/2017/07/009038.

Thalictrum foliolosum: A lesser unexplored medicinal herb from the Himalayan region as a source of valuable benzyl isoquinoline alkaloids

ETHNOPHARMACOLOGICAL RELEVANCE

Thalictrum foliolosum DC (Ranunculaceae) is a perennial flowering herb traditionally used as a tonic, antiperiodic, diuretic, febrifuge, purgative and stomachic and for the treatment of snakebite, jaundice, and rheumatism.

AIM OF THE STUDY

To provide a critical assessment of the state-of-the-art related to the traditional uses, phytochemistry, and pharmacology of T. foliolosum with the ultimate objective of providing further research strategies to facilitate the exploitation of the therapeutic potential of T. foliolosum for the treatment of human disorders.

MATERIALS AND METHODS

Exhaustive bibliographic research related to T. foliolosum plant was carried out using scientific research engines and databases such as Google Scholar, PubMed, Web of Science covering all retrieved relevant manuscripts written in English.

RESULTS

Several alkaloids such as berberine, jatrorrhizine, palmatine, thalrugosidine, thalrugosaminine, thalisopine (thaligosine), thalirugidine, thalirugine, 8-oxyberberine (berlambine), noroxyhydrastinine, N,O,O-trimethylsparsiflorine, thalicarpine, thalidasine, thalfoliolosumines A and thalfoliolosumines B were reported from T. foliolosum. Ethnomedicinal studies revealed much wider scope of T. foliolosum in developing various drugs to solve multiple challenges in the health sector. Therapeutic effects were attributed to the bioactivities of the secondary metabolites present in T. foliolosum.

CONCLUSIONS

T. foliolosum is rich in berberine and other benzylisoquinoline alkaloids. T. foliolosum can be used as an excellent and effective herbal remedy for various human ailments since there are no reports on the toxicity of this herb.

SAT0219 PATIENT CHARACTERISTICS, TREATMENT PATTERNS, AND RESOURCE UTILIZATION OF SJOGREN’S SYNDROME PATIENTS IN A LARGE US HEALTH NETWORK

Background:

Sjogren’s syndrome (SS) is a chronic progressive autoimmune disorder which occurs as primary (pSS) or secondary SS (sSS). With no approved disease modifying therapy, there is limited information on the treatment patterns and resource utilization among these patients (pts).

Objectives:

To describe pts characteristics, treatment patterns and healthcare resource utilization (HCRU) using electronic health records (EHR) of pts with pSS and sSS treated at the Providence St. Josephs Health system (PSJH).

Methods:

Pts ≥18 years of age with at least one clinical encounter with ICD-9-CM or ICD-10-CM diagnosis of SS, between Jan 2013 and Mar 2019 were included. Date of first encounter with SS diagnosis (index date) was used to assess pts demographics. Pt baseline comorbidities were evaluated during the 24 months pre-index period. Treatment patterns and HCRU were assessed during the 12 months post-index follow-up. Descriptive statistics were used to describe pts’ demographic and clinical characteristics, and medications use in the baseline and follow up.

Results:

Study cohort included 9,108 SS pts of which 76.5% had sSS diagnosis on index date. Majority of SS pts were women, Caucasian, with mean age of 58.3 yrs, and from western states in the US (Table 1). Endocrine conditions including hypo- and hyperthyroidism, and diabetes was the most common (45.5%) comorbidity at baseline, followed by rheumatologic disorders (25.6%) and neurological conditions (22.2%). Among patients with treatment information (4088, 44.88%), 42.95% were using symptomatic treatments for dry eye and mouth at baseline (Table 1). In the follow-up, SS pts had average 5.8 healthcare visits per patient per year (PPPY), including 0.6 inpatient and 3.4 outpatient visit respectively. About 40% of the SS pts (53.8% pSS and 35.8% sSS) were diagnosed by rheumatologists. Majority of the SS pts initiated treatment with cDMARDs (82%) and remained on the same treatment during 1 year follow-up (Fig 2).

Table 1.

Baseline Demographic and Clinical Pts Characteristics

SS Pts (n=9,108)DemographicsAge (years) on index date, mean (SD)58.3 (15.1)Female, n (%)8,338 (91.6)Caucasian, n (%)6.936 (76.2)Western Region, n (%)8,998 (98.8)Married, n (%)5,164 (56.7)Never Smoked, n (%)4,847 (53.2)Primary diagnosis, n (%)2,137 (23.5)Comorbidities, n (%)Cardiovascular1,408 (17.2)Endocrine3,733 (45.5)Oncology800 (9.8)Blood disorders1,221 (14.9)Pulmonary1,802 (22.0)Neurological1,821 (22.2)Liver/Kidney1,782 (21.7)Rheumatologic disorders2,096 (25.6)Autoimmune/ Immune related1,527 (18.6)Baseline Medications, n (%)Symptomatic11,756 (43.0)NSAIDs21,578 (38.6)cDMARDs31,435 (35.1)Corticosteroid41,393 (34.1)bDMARDs5266 (6.5)

1cevimeline, pilocarpine hydrochloride, ophthalmic insert etc;2aspirin, ibuprofen, naproxen;3methotrexate, hydroxychloroquine, sulfasalazine, leflunomide, myophenolate mofetil, azathioprine;4prednisone;5sarilumab, belimumab, ustekinumab, infliximab, adalimumab, certolizumab pegol, golimumab, etanercept, abatacept, tocilizumab, rituximab, tofacitinib, baricitinib

Figure 1.

HCRU for pSS and sSS Pts

Figure 2.

Treatment Sequencing for pSS and sSS Pts. Note: Discontinued: pts who discontinued and didn’t advance to any therapy; same treatment: pts continued on index treatment till we have information.

Conclusion:

Observation of higher comorbidities suggests substantial burden of SS pts on healthcare system, with majority of pts being diagnosed outside of rheumatology offices.

Acknowledgments: :

We acknowledge the contributions of Manasi Suryavanshi towards drafting and reviewing the abstract.

Disclosure of Interests:

Philip J Mease Grant/research support from: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – grant/research support, Consultant of: Abbott, Amgen, Biogen Idec, BMS, Celgene Corporation, Eli Lilly, Novartis, Pfizer, Sun Pharmaceutical, UCB – consultant, Speakers bureau: Abbott, Amgen, Biogen Idec, BMS, Eli Lilly, Genentech, Janssen, Pfizer, UCB – speakers bureau, Joe Zhuo Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Roshanthi Weerasinghe Grant/research support from:., Qian Xia Shareholder of: I own shares of Bristol-Myers Squibb Company, Employee of: I am a paid employee of Bristol-Myers Squibb Company, Chidananda Samal Consultant of: I work as a consultant for Bristol-Myers Squibb Company, Niyati Sharma Consultant of: I work as a consultant for Bristol-Myers Squibb Company

SAT0129 ROLE OF SHARED EPITOPE ON THE EFFECTIVENESS OF TNFI TREATMENT FOR PATIENTS WITH RHEUMATOID ARTHRITIS

Background:

Rheumatoid arthritis (RA) has been shown a strong genetic association with particularHLA–DRB1alleles containing shared epitope (SE). However, whether SE is clinically useful in treatment choices is insufficiently investigated1and previous studies have presented mixed findings in the role of SE in the response of TNFi therapies2,3.

Objectives:

To assess the role of SE in response to TNFi treatment in real-world RA patients (pts).

Methods:

Pts enrolled in a large RA registry, Brigham and Women’s Hospital RA Sequential Study, with known SE and received TNFi therapies were included for the analysis. TNFi pts were identified by the first-time use of the drugs between March 2003 to June 2018. For this analysis, all pts were followed up to 1 year. Summary statistics are reported for demographics, serostatus and disease activity (DA) at baseline and follow-up, stratified by SE status. Given the strong association of SE and anti-citrullinated protein antibody (ACPA), the analysis was further stratified by ACPA status. The effect of SE on change in DA was assessed using linear regression model with age, gender, RA disease duration, baseline DA, smoking status, SE, ACPA and ACPA-SE interaction as covariates.

Results:

Of the 484 TNFi pts included in the study, 68.8% were SE+. SE+ pts (vs SE-) were more likely to be rheumatoid factor positive, have erosive disease and a higher disease duration, irrespective of ACPA status. No difference in the change of DA was observed by SE. In SE- pts, ACPA+ pts had a greater reduction of DA than ACPA- pts (Table 1). After accounting for baseline differences, there was no significant effect of SE status on the mean change from baseline in any of the 3 DA measures.(Figure 1) The change in DA was not associated with ACPA but was significantly affected by disease duration and baseline DA.

Table 1.

Disease Activity in TNFi Patients, Stratified by SE and ACPA Status

ParameterSE+ (1 & 2 alleles, n=333)SE- (n=151)ACPA+ACPA–OverallACPA+ACPA-Overall(n=264)(n=69)(n=333)(n=90)(n=61)(n=151)Baseline, Mean (SD)DAS28 CRP3.94 (1.69)3.57 (1.61)3.86 (1.67)3.85 (1.49)3.45 (1.65)3.69 (1.57)CDAI23.06 (18.13)18.95 (15.96)22.25 (17.78)21.91 (15.96)17.72 (17.06)20.26 (16.48)SDAI24.08 (18.82)19.96 (16.59)23.27 (18.45)22.58 (16.34)18.55 (17.87)20.99 (17.01)Follow-up, Mean (SD)DAS28 CRP3.42 (1.55)2.69 (1.32)3.27 (1.53)3.19 (1.43)3.11 (1.53)3.16 (1.47)CDAI17.61 (15.53)12.11 (12.65)16.51 (15.14)15.15 (13.35)14.94 (14.73)15.07 (13.84)SDAI18.35 (15.73)12.45 (12.78)17.15 (15.34)15.31 (13.81)15.71 (15.45)15.46 (14.38)Change, Mean (SD)DAS28 CRP-0.48 (1.31)-0.65 (1.53)-0.52 (1.36)-0.52 (1.50)-0.24 (0.93)-0.42 (1.34)CDAI-4.29 (13.16)-4.79 (13.13)-4.39 (13.12)-6.45 (13.56)-2.63 (9.58)-4.99 (12.28)SDAI-4.74 (14.13)-5.07 (13.90)-4.80 (14.05)-6.87 (14.21)-2.97 (10.32)-5.41 (12.98)Figure 1.

Linear Regression Model for Change in Disease Activity*Estimates, p-values are shown as data labels on the graphs; The above model is adjusted for age, gender, RA duration, smoking status, SE status, baseline DA, ACPA and ACPA*SE status

Conclusion:

This real-world study validates the finding from previous studies conducted in clinical settings that SE does not differentiate treatment response for TNFi therapies.

References:

[1]Saruhan-Direskeneli G, et al.Rheumatology (Oxford) 2007;46(12):1842-44

[2]Skapenko A, et al.Clin Exp Rheumatol2019;37(5):783-790

[3]Rigby W, et al.Annals of the Rheumatic Diseases2019;78(2):263-264

Disclosure of Interests:

Joe Zhuo Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Joshua Bryson Shareholder of: I own shares of Bristol-Myers Squibb Company, Employee of: I am a paid employee of Bristol-Myers Squibb Company, Qian Xia Shareholder of: I own shares of Bristol-Myers Squibb Company, Employee of: I am a paid employee of Bristol-Myers Squibb Company, Niyati Sharma Consultant of: I work as a consultant for Bristol-Myers Squibb Company, Chidananda Samal Consultant of: I work as a consultant for Bristol-Myers Squibb Company, Sonie Lama Shareholder of: I own shares of Bristol-Myers Squibb Company., Employee of: I am a paid employee of Bristol-Myers Squibb Company., Michael E. Weinblatt Grant/research support from: BMS, Amgen, Lilly, Crescendo and Sonofi-Regeneron, Consultant of: Horizon Therapeutics, Bristol-Myers Squibb, Amgen, Abbvie, Crescendo, Lilly, Pfizer, Roche, Gilead, Nancy Shadick Grant/research support from: Mallinckrodt, BMS, Lilly, Amgen, Crescendo Biosciences, and Sanofi-Regeneron, Consultant of: BMS

SAT0061 ROLE OF SHARED EPITOPE IN THE PROGNOSIS OF RHEUMATOID ARTHRITIS IN RELATION TO ACPA POSITIVITY

Background:

The mechanistic association ofHLA-DRB1alleles that code a “shared epitope” (SE) with rheumatoid arthritis (RA) is not yet clear. Previous data has suggested the carriage of SE is associated with the production of cyclic citrullinated peptide antibodies (anti-CCP)1and severe RA2-4. The interrelationship among SE, anti-citrullinated protein antibody (ACPA) positivity and disease outcomes is not fully understood.

Objectives:

To assess the RA prognosis associated with the carriage of SE, in relation to ACPA positivity.

Methods:

Pts enrolled in a large RA registry, Brigham and Women’s Hospital RA Sequential Study between March 2003 to June 2018, with known SE and ACPA status were included in the analysis. HLA-DRB1 SE status was determined by allele-specific polymerase chain reaction and DNA sequencing for most of the subjects and by GWAS-based imputation for the rest. Disease activity (DA) was measured at baseline (BL) and 1-year follow-up by DAS28(CRP), CDAI and SDAI. Pts were stratified by SE+ (1 or 2 SE alleles) and SE- (0 alleles) and ACPA status. We analyzed the relationship of SE with ACPA positivity and change in DA by a linear regression model separately. A mediation analysis was used to examine the mediating effect of ACPA on association between SE and change in DA.

Results:

Out of 926 pts included in the analysis, 65.1% were SE+, of whom 75.6% were ACPA+. In comparison, 51.7% were ACPA+ in SE- pts. SE+ pts were similar with SE- pts in age, gender, BMI and smoking status, but had longer disease duration, were more likely to be rheumatoid factor positive, have erosive disease and higher comorbidity burden irrespective of ACPA status. The differences were more pronounced if the pts were also ACPA+. Adjusting for BL differences, pts with SE 1 and 2 alleles (vs 0) had an odd ratio of 1.97 (95% CI:1.36-2.84; p=0.0003) and 3.82 (95% CI: 2.44-5.98; p<.0001) to be ACPA +, respectively. The regression analysis suggests that SE+ (vs SE-) pts had an average increase in DAS28 (CRP) of 0.22 (p=0.033), CDAI of 2.07 (p=0.045) and SDAI of 2.43 (p=0.029) over a year (Fig 1). Using a mediation analysis, the direct effect of SE+ account for 78.8% to 81.0% of total effect in the increase in DAS28 (CRP), CDAI and SDAI, and the indirect effect mediated by ACPA account for 19.0% to 21.2% (Table 1).

Table 1.

Mediation Analysis for SE and ACPA Association with Change in DA

ParameterChange in DAS28 CRP (N=666)Change in CDAI (N=653)Change in SDAI (N=629)EstimateP-valueEstimateP-valueEstimateP-valueTotal Effect of SE on DA change0.220.0342.050.0472.400.030Direct effect of SE on DA change excluding mediation of ACPA0.170.1011.570.1401.890.098Indirect effect of SE on DA change due to ACPA mediation and interaction0.040.1830.480.1330.510.143

The model is adjusted with other covariates: Age, Gender, Charlson comorbidity score; baseline biologic use, Smoking status, baseline DA, Interaction term (ACPA*SE)

Figure 1.

Linear Regression Model for SE Association with Change in Disease Activity *Estimates, p-values are shown as data labels on the graphs; Change in disease activity (DA) = (follow-up DA- baseline DA); The above model is adjusted for age, gender, CCI, baseline DA, baseline biologic use, SE status and smoking status

Conclusion:

SE is strongly related to ACPA and a greater burden of disease in RA pts. In pts receiving standard treatments including biologics, SE is predictive of a greater increase in DA, which is partially mediated by the presence of ACPA.

References:

[1] Dayan I, et al.,Arch of Rheumatology, 2010;25:012-018.

[2] Gregerson PK, et al,Arthritis Rheum. 1987;30:1205-1213.

[3] Turesson C, et al.Arthritis Res Ther. 2005;7:R1386-1393.

[4] Moreno I, et al.J Rheumatol. 1996;23:6-9.

Disclosure of Interests:

Joe Zhuo Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Joshua Bryson Shareholder of: I own shares of Bristol-Myers Squibb Company, Employee of: I am a paid employee of Bristol-Myers Squibb Company, Qian Xia Shareholder of: I own shares of Bristol-Myers Squibb Company, Employee of: I am a paid employee of Bristol-Myers Squibb Company, Niyati Sharma Consultant of: I work as a consultant for Bristol-Myers Squibb Company, Sheng Gao Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, Sonie Lama Shareholder of: I own shares of Bristol-Myers Squibb Company., Employee of: I am a paid employee of Bristol-Myers Squibb Company., Michael E. Weinblatt Grant/research support from: BMS, Amgen, Lilly, Crescendo and Sonofi-Regeneron, Consultant of: Horizon Therapeutics, Bristol-Myers Squibb, Amgen, Abbvie, Crescendo, Lilly, Pfizer, Roche, Gilead, Nancy Shadick Grant/research support from: Mallinckrodt, BMS, Lilly, Amgen, Crescendo Biosciences, and Sanofi-Regeneron, Consultant of: BMS

Ultra-High-Frame-Rate Ultrasound Monitoring of Muscle Contractility Changes Due to Neuromuscular Electrical Stimulation

The quick onset of muscle fatigue is a critical issue when applying neuromuscular electrical stimulation (NMES) to generate muscle contractions for functional limb movements, which were lost/impaired due to a neurological disorder or an injury. For in situ assessment of the effect of NMES-induced muscle fatigue, a novel noninvasive sensor modality that can quantify the degraded contractility of a targeted muscle is required. In this study, instantaneous strain maps of a contracting muscle were derived from ultra-high-frame-rate (2 kHz) ultrasound images to quantify the contractility. A correlation between strain maps and isometric contraction force values was investigated. When the muscle reached its maximum contraction, the maximum and the mean values of the strain map were correlated with the force values and were further used to stage the contractility change. During the muscle activation period, a novel methodology based on the principal component regression (PCR) was proposed to explore the strain-force correlation. The quadriceps muscle of 3 able-bodied human participants was investigated during NMES-elicited isometric knee extension experiments. Strong to very strong correlation results were obtained and indicate that the proposed measurements from ultrasound images are promising to quantify the muscle contractility changes during NMES.

Abstract A31: Tracking the evolution of soft tissue sarcoma and GIST using liquid biopsies

Molecular analysis of circulating tumor DNA (ctDNA) has a large potential for clinical application by capturing mutations and heterogeneity through noninvasive sampling. The CircSarc studies aims to provide new insights into the clinical utility of liquid biopsies in soft tissue sarcomas (CircSarc STS) and gastrointestinal stromal tumors (CircSarc GIST). In CircSarc STS, we have enrolled 35 high-grade soft-tissue sarcoma patients with localized disease. Plasma from each patient has been collected longitudinally throughout the course of their disease, with a follow-up of up to 5 years. To identify patient-specific somatic mutations, the patients’ tumor and germline DNA have been exome sequenced. Somatic mutations in cfDNA are being identified using ultra-low-pass WGS or targeted NGS. At time of surgery and/or progression, we detect ctDNA in 30% of the first soft-tissue sarcoma samples with higher levels in larger or metastatic tumors. In a proof-of-concept study, we have shown that that levels of tumor-specific mutations in plasma correlated to clinical manifestation of metastatic disease. In CircSarc GIST, plasma has been collected for a cohort of 30 metastatic GISTs and at time of diagnosis for 50 GISTs. Somatic mutations in the tumor have been determined by targeted sequencing or whole-exome sequencing. Somatic mutations in ctDNA are identified using targeted NGS. The levels of somatic mutations in ctDNA are being correlated with clinicopathologic features. ctDNA was detected in 36% of treatment-naïve GIST patients, including all patients with metastatic disease, and the tumor burden was the most important detection determinant. Analysis of metastatic GISTs is ongoing, but repeated plasma samples in a progressing patient have demonstrated that clonal evolution can be monitored over time. ctDNA analysis of the patient revealed multiple resistance mutations, and these were spatially distributed in the primary tumor. Our work shows that detection of mutations in plasma is particularly feasible for patients with high tumor burden. Mutational analysis by use of liquid biopsies can capture the molecular heterogeneity of the tumor and guide treatment decisions during progression.

Citation Format: Heidi M. Namløs, Kjetil Boye, Seyed H Moosavi, Daniel Vodak, Nitin Sharma, Susanne Lorenz, Bodil Bjerkehagen, Stine Næss, Eivind Hovig, Nina Jebsen, Anders Ståhlberg, Ola Myklebost, Leonardo A. Meza-Zepeda. Tracking the evolution of soft tissue sarcoma and GIST using liquid biopsies [abstract]. In: Proceedings of the AACR Special Conference on Advances in Liquid Biopsies; Jan 13-16, 2020; Miami, FL. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(11_Suppl):Abstract nr A31.

Mechanistic Insights into Zika Virus NS3 Helicase Inhibition by Epigallocatechin-3-Gallate

Since 2007, repeated outbreaks of Zika virus (ZIKV) have affected millions of people worldwide and created a global health concern with major complications like microcephaly and Guillain Barre's syndrome. To date, there is not a single Zika-specific licensed drug present in the market. However, in recent months, several antiviral molecules have been screened against ZIKV. Among those, (-)-epigallocatechin-3-gallate (EGCG), a green tea polyphenol, has shown great virucidal potential against flaviviruses including ZIKV. The mechanistic understanding of EGCG-targeting viral proteins is not yet entirely deciphered except that little is known about its interaction with viral envelope protein and viral protease. We designed our current study to find inhibitory actions of EGCG against ZIKV NS3 helicase. NS3 helicase performs a significant role in viral replication by unwinding RNA after hydrolyzing NTP. We employed molecular docking and simulation approach and found significant interactions at the ATPase site and also at the RNA binding site. Further, the enzymatic assay has shown significant inhibition of NTPase activity with an IC₅₀ value of 295.7 nM and Ki of 0.387 ± 0.034 μM. Our study suggests the possibility that EGCG could be considered as a prime backbone molecule for further broad-spectrum inhibitor development against ZIKV and other flaviviruses.

Saccharomyces cerevisiae polo-like kinase, Cdc5 exhibits ATP-dependent Mg2+-enhanced kinase activity in vitro

Phosphorylation of proteins on serine/threonine residues represents an important biochemical mechanism to regulate several cellular processes. Polo-like kinases (PLKs) are a family of serine-threonine kinases that play an imminent role in cell cycle regulation in yeast to humans, and thus an important therapeutic target for cancers. The present study provides insights into the enzymatic features of Saccharomyces cerevisiae PLK, Cdc5 using in vitro casein phosphorylation assays. The recombinant yeast PLK, GST-Cdc5 showed maximum casein phosphorylation activity at 30 °C, pH 9 and 45 min of incubation period. GST-Cdc5 exhibited a K_M of 1.35 μM for casein, and high affinity for ATP, since addition of non-radioactive ATP chased out casein phosphorylation by radiolabeled ATP. The recombinant enzyme showed maximum kinase activity at 2.7 μM of GST-Cdc5. Casein was found to be the best in vitro substrate of GST-Cdc5 followed by BSA (Bovine Serum Albumin) and MBP (Myelin Basic Protein). Of the metal ions tested, Mg²⁺ (at 20 mM) was found to enhance GST-Cdc5 kinase activity, while Ca²⁺ (at 5 mM) and Mn²⁺ (at 10 mM) inhibited the same. The presence of EDTA, SDS and PMSF inhibited phosphorylation by GST-Cdc5, while DTT had no effect. The recombinant GST-Cdc5 can be used as a tool for deciphering PLKs’ structure and functions, which are still at infancy.

Using Person-Specific Muscle Fatigue Characteristics to Optimally Allocate Control in a Hybrid Exoskeleton - Preliminary Results

Currently controllers that dynamically modulate functional electrical stimulation (FES) and a powered exoskeleton at the same time during standing-up movements are largely unavailable. In this paper, an optimal shared control of FES and a powered exoskeleton is designed to perform sitting to standing (STS) movements with a hybrid exoskeleton. A hierarchical control design is proposed to overcome the difficulties associated with developing an optimal real-time solution for the highly nonlinear and uncertain STS control model with multiple degrees of freedom. A higher-level robust nonlinear control design is derived to exponentially track a time-invariant desired STS movement profile. Then, a lower-level optimal control allocator is designed to distribute control between FES and the knee electric motors. The allocator uses a person's muscle fatigue and recovery dynamics to determine an optimal ratio between the FES-elicited knee torque and the exoskeleton assist. Experiments were performed on human participants, two persons without disability and one person with spinal cord injury (SCI), to validate the feedback controller and the optimal torque allocator. The muscles of the participant with SCI did not actively contract to FES, so he was only tested with the powered exoskeleton controller. The experimental results show that the proposed hierarchical control design is a promising method to effect shared control in a hybrid exoskeleton.