Long-term effectiveness of transforaminal anterolateral approach CT-guided cervical epidural steroid injections for cervical radiculopathy treatment

AIM

To evaluate the long-term clinical effectiveness of computed tomography (CT)-guided transforaminal cervical epidural steroid injection using an anterolateral approach for the treatment of cervical radiculopathy (CR) using well-established robust clinical scoring systems for neck pain and neck disability. Despite its widespread use, evidence to support the long-term benefit of routine cervical epidural steroid injection is currently very limited.

MATERIALS AND METHODS

This study included 113 patients with magnetic resonance imaging (MRI)-confirmed CR who underwent a steroid injection at a single cervical level via a unilateral transforaminal anterolateral approach. Pain was assessed quantitatively at pre-injection, 15 minutes post-injection, 1 month, 3 months, and at 1 year. Neck disability was assessed using the Oswestry Neck Disability Index (NDI) at pre-injection, 1 month, 3 months, and 1 year time points.

RESULTS

Eighty patients completed the study. Sixty per cent reported reduced neck pain (mean pain reduction, 55%), which was clinically significant in 45% cases. Furthermore, 66% reported an improvement in neck disability (mean improvement, 51%), which was clinically significant for 56% patients. Clinically significant good outcomes in both neck pain and neck disability were evident from as early as 1-month, and importantly, were independent both of pre-treatment CR characteristics (including severity of pre-injection neck pain or disability) and of findings on pre-injection MRI imaging.

CONCLUSION

Transforaminal anterolateral approach CT-guided epidural steroid injection resulted in a clinically significant long-term improvement in both neck pain and disability for half of the present cohort of patients with unilateral single-level CR. This improvement was independent of the severity of the initial symptoms and pre-injection MRI findings.

Post-COVID syndrome: analysis of the prevalence of chemosensory dysfunction and predictive factors of recovery in COVID-19 long-haulers in Jordan

OBJECTIVE

One of the major concerns of the post-COVID-19 era is elucidating and addressing the long-term complications of COVID-19.

SUBJECTS AND METHODS

A web-based questionnaire was distributed in Jordan to assess the prevalence and recovery from chemosensory dysfunction among COVID-19 long-haulers in Jordan.

RESULTS

A total of 611 respondents complained of chemosensory dysfunction (age range = 18-68 years), and the majority of the respondents were female (88.4%). Parosmia was the most prevalent olfactory dysfunction reported (n = 337, 33.3%), and parageusia was the most frequently reported gustatory dysfunction (n = 239, 36.4%). Medications were not reported to be associated with a better perception of smell or taste by nearly half of those who had been treated (n = 146, 46.1%). Among participants who had received olfactory rehabilitation/training (n = 215, 35.2%), 43.7% (n = 94) reported modest improvement, with the most frequently helpful scents being coffee (n = 80, 24.8%), aromatic oils (n = 74, 23%), and perfumes/colognes (n = 73, 22.7%). Age was found to have a significant negative correlation with complete recovery. In addition, age (p < .05), anosmia (p < .001), hyperosmia (p < .001), ageusia (p < .05), and duration of olfactory dysfunction (p < .001) were all independent predictors of complete recovery.

CONCLUSIONS

Chemosensory dysfunctions are largely subjective; therefore, more objective examinations are required to draw more definite conclusions.

Transformation of Rhodococcus Pigment Production Hydroxylase (PPH) gene into Camelina sativa: an alternative marker for the detection of transgenic plants

Abstract Production of transgenic plants with desired agronomic and horticultural traits has gained great importance to fulfill demands of the growing population. Genetic transformation is also a fundamental step to study basics of plant sciences. Different transformation protocols have been developed and used which are reliable and efficient. These protocols used antibiotic or herbicide resistance genes incorporated along with gene of interest to identify transformed plants from non-transformed ones. These marker genes may pose a threat to human and environment. Use of visual markers enables direct and easier observation of transformed plants with more precision. In current study a gene cassette with ‘pigment production hydroxylase (PPH) gene under fiber specific promoter (GhSCFP) and downstream Nos-terminator was designed. After checking the structural and functional efficiency of codon optimized gene using bioinformatics tools, the cassette was sent for chemical synthesis from commercial source. The pigment gene cassette (PPH_CEMB), cloned in pCAMBIA-1301, was transformed into Agrobacterium through electroporation. Agrobacterium-mediated floral dip method was used to transform Camelina sativa inflorescence. After seed setting a total of 600 seed were observed for change in color and out of these, 19 seeds developed a reddish-brown coloration, while the remaining 581 seeds remained yellow. The transformation efficiency calculated on basis of color change was 1.0%. PCR analysis of leaves obtained after sowing reddish seeds confirmed the transformation of pigment production gene, while no PCR amplification was observed in leaves of plants from wild type seeds. From the results it is evident that Agrobacterium-mediated transformation of C. sativa inflorescence is very efficient and environment friendly technique not only for detection of transformed plants but also to study basic cellular processes.

Variation of Acromiocoracoid and Acromioglenoid Distance in Bangladeshi People

This cross-sectional descriptive purposive study was done on 150 (70 right and 80 left) fully ossified dry human scapulae of Bangladeshi people to find out the variation in length of acromiocoracoid and acromioglenoid distance. Sample collection was carried out in the Department of Anatomy, Mymensingh Medical College, Bangladesh from January to December 2019. Any kind of damaged or broken scapulae were excluded to maintain standard measurement. Length of these distances was measured with the help of digital Vernier slide calipers. The mean±SD acromiocoracoid distance were 35.8±4.64 mm and 36.32±5.55 mm on right and left sided scapulae respectively and the mean±SD acromioglenoid distance were 27.69±3.43 mm on right sided scapulae and 28.18±3.26 mm on left sided scapulae. These data are important to compare Bangladeshi scapulae to those from various other races that could contribute to demographic studies of shoulder disease probability and management in Bangladeshi population.

Ship Breaking Workers and Their Pattern of Work-Related Respiratory Problems: A Cross-sectional Study at Sitakunda Ship Breaking Industrial Area of Bangladesh

A cross-sectional study was conducted from March 2019 to August 2019 to determine the pattern of work-related respiratory problems among workers in ship breaking industry at Sitakunda, Chittagong, Bangladesh as many unskilled and semiskilled worker are working there without having minimum knowledge and idea about the possible adverse health effect of different pollutants which also pose threats to the ambient environment. Total 120 male respondents were selected purposively. Majority 80.8% (97) of the workers were below 30 years. About 71.0% (85) respondents were working for less than five years. Majority of respondents worked 8 hours daily. Most of them worked each of the days in a week. About 66.0% (80) had smoking habit. Among 120 respondents, 95.8% (115) had no previous respiratory problem. But 63.3% (76) felt that their respiratory problems were increasing day by day due to current job (ship breaking). There were 85.0% (102) respondents who felt cold or sneeze mostly in working place. About 80.0% (96) of respondents felt better during holiday. There were different respiratory symptoms among the respondents like nasal irritation, hoarseness of voice, cough during cold, cough without cold, bringing up phlegm when catch cold, bringing up phlegm without cold, tightness of chest where the prevalence was 54.2% (65), 85.0% (102), 93.3% (112), 28.3% (34), 70.0% (84), 39.0% (27) and 67.5% (81) respectively among the workers. Majority respondents 96.7% (116) were conscious about using PPE. Only 17.5% (21) used mask during work. Different pulmonary lung function test like forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), FEV1%, peak expiratory flow rate (PFER) was done. Mean of FVC, FEV1 was 3.76 and 1.09 respectively. According to pulmonary statuses of workers as per spirometric findings 20.83% (25) had normal pulmonary function, 58.33% (45) had obstruction and 20.83% (25) had combined obstructive parameters. So in light of the study it is clear that the work organization has not developed in this particular industry. In every steps of their work ship breaking workers are facing violations of industrial codes which correspond with safe working environment. In long run the workers have to pay with their health and life about which they are unaware.

Multidisciplinary Management of Phyllodes Tumours and Breast Sarcoma: A Cross-sectional Survey of Clinical Practice across the UK and Ireland

AIMS

Phyllodes tumours and breast sarcomas are uncommon tumours and their rarity poses significant challenges in diagnosis and management. This cross-sectional study was conducted to evaluate the multidisciplinary clinical practice for these tumours across the UK and Ireland, with the aim of identifying gaps in knowledge and providing direction for establishing national guidelines.

MATERIALS AND METHODS

An international survey was adapted and circulated to breast and/or sarcoma surgeons and oncologists in the UK and Ireland through national organisations. Multidisciplinary team (MDT) responses were analysed anonymously.

RESULTS

Twenty-eight MDTs participated in this study, predominately from high-volume units (85.5%). Although only 43% of the surveyed units were part of a trust that holds a sarcoma MDT, 68% of units managed malignant phyllodes and angiosarcoma, whereas 64.5% managed soft-tissue sarcoma of the breast. Across all subtypes, axillary surgery was recommended by 14-21% of the MDTs and the most recommended resection margins for breast surgery were 'no tumour on ink' in benign phyllodes (39%) and 10 mm in the remaining subtypes (25-29%). Immediate breast reconstruction was supported by 11-18% of MDTs for breast sarcoma subtypes, whereas 36% and 32% advocated this approach in benign and borderline phyllodes tumours, respectively. Adjuvant radiotherapy and chemotherapy were recommended by up to 29% and 11% of the MDTs, respectively.

CONCLUSION

The results of this study demonstrate a wide variation in clinical practice across the surveyed MDTs. As only 28 MDTs participated in our study, with under-representation from low-volume units, our results might be an underestimation of the variability in practice across the UK and Ireland. This multi-institutional study sheds light on controversial aspects in the management of phyllodes tumours and breast sarcoma, identifies the need for national guidelines to inform best practice, and calls for the centralisation of the management of breast sarcoma within specialist centres.

Anatomical Study of Number, Location and Position of Nutrient Foramina of Fully Ossified Dry Human Humerus

The nutrient foramen is the natural opening present in the shaft of the humerus. It passes the nutrient artery to the medullary cavity. The nutrient artery is the chief artery that enters the bone through a nutrient foramen to provide nutrition for its growth. It plays an important role in healing during fracture and trauma and is also important for bone grafting. This study aimed to determine the common location, position and number of nutrient foramina of fully ossified dry human humerus. One hundred samples (right- 43 and left- 57) were selected through the purposive sampling technique for this cross-sectional descriptive study carried out in the Department of Anatomy, Mymensingh Medical College, Bangladesh from July 2021 to June 2022. Any damaged, unossified bones or fractured bones were excluded. Data were tabulated and statistically analyzed using Microsoft Excel and SPSS software. Among 43 right humeri, 37(75.51%) have single-nutrient foramen and 06(24.49%) have double-nutrient foramina. Among 57 left humeri, 53(92.98%) have single nutrient foramen, 03(5.27%) have double nutrient foramina and 01(1.75%) has triple nutrient foramina. In case of location of nutrient foramina, among 49 right nutrient foramina, 45(91.84%) were found on the anteromedial surface, 02(4.08%) were found on the anterolateral surface and 02(4.08%) were on the posterior surface of the shaft of the humerus. In case of 62 left nutrient foramina, 57(91.94%) were found on the anteromedial surface and 05(8.06%) were found on the posterior surface of the shaft of the humerus. Among 49 right nutrient foramina, 01(2.04%) was found on the upper third, 46(93.88%) on the middle third and 02(4.08%) on the lower third of the shaft of the humerus. In case of 62 left nutrient foramina, 01(1.60%) was on the upper third, 57(91.95%) were on the middle third and 04(6.45%) were on the lower third of the shaft of the humerus.

Investigation of BAK, BAX and MAD2L1 gene expression in human aneuploid blastocysts

Maintaining genomic stability is crucial for normal development. At earlier stages of preimplantation development, as the embryonic genome activation is not fully completed, the embryos may be more prone to abnormalities. Aneuploidies are one of the most common genetic causes of implantation failure or first-trimester miscarriages. Apoptosis is a crucial mechanism to eliminate damaged or abnormal cells from the organism to enable healthy growth. Therefore, this study aimed to determine the relationship between the expression levels of genes involved in apoptosis in human aneuploid and euploid blastocysts. In total, 32 human embryos obtained from 21 patients were used for this study. Trophectoderm biopsies were performed and next-generation screening was carried out for aneuploidy screening. Total RNA was extracted from each blastocyst separately and cDNA was synthesized. Gene expression levels were evaluated using RT-PCR. The statistical analysis was performed to evaluate the gene expression level variations in the euploid and aneuploid embryos, respectively. The expression level of the BAX gene was significantly different between the aneuploid and euploid samples. BAX expression levels were found to be 1.5-fold lower in aneuploid cells. However, the expression levels of BAK and MAD2L1 genes were similar in each group. This study aimed to investigate the possible role of genes involved in apoptosis and aneuploidy mechanisms. The findings of this investigation revealed that the BAX gene was expressed significantly differently between aneuploid and euploid embryos. Therefore, it is possible that the genes involved in the apoptotic pathway have a role in the aneuploidy mechanism.

Association of polygenic score and the involvement of cholinergic and glutamatergic pathways with lithium treatment response in patients with bipolar disorder

Lithium is regarded as the first-line treatment for bipolar disorder (BD), a severe and disabling mental health disorder that affects about 1% of the population worldwide. Nevertheless, lithium is not consistently effective, with only 30% of patients showing a favorable response to treatment. To provide personalized treatment options for bipolar patients, it is essential to identify prediction biomarkers such as polygenic scores. In this study, we developed a polygenic score for lithium treatment response (Li+PGS) in patients with BD. To gain further insights into lithium's possible molecular mechanism of action, we performed a genome-wide gene-based analysis. Using polygenic score modeling, via methods incorporating Bayesian regression and continuous shrinkage priors, Li+PGS was developed in the International Consortium of Lithium Genetics cohort (ConLi+Gen: N = 2367) and replicated in the combined PsyCourse (N = 89) and BipoLife (N = 102) studies. The associations of Li+PGS and lithium treatment response - defined in a continuous ALDA scale and a categorical outcome (good response vs. poor response) were tested using regression models, each adjusted for the covariates: age, sex, and the first four genetic principal components. Statistical significance was determined at P < 0.05. Li+PGS was positively associated with lithium treatment response in the ConLi+Gen cohort, in both the categorical (P = 9.8 × 10-12, R2 = 1.9%) and continuous (P = 6.4 × 10-9, R2 = 2.6%) outcomes. Compared to bipolar patients in the 1st decile of the risk distribution, individuals in the 10th decile had 3.47-fold (95%CI: 2.22-5.47) higher odds of responding favorably to lithium. The results were replicated in the independent cohorts for the categorical treatment outcome (P = 3.9 × 10-4, R2 = 0.9%), but not for the continuous outcome (P = 0.13). Gene-based analyses revealed 36 candidate genes that are enriched in biological pathways controlled by glutamate and acetylcholine. Li+PGS may be useful in the development of pharmacogenomic testing strategies by enabling a classification of bipolar patients according to their response to treatment.

Phytochemical Composition, Antioxidant, Antimicrobial, Antibiofilm, and Antiquorum Sensing Potential of Methanol Extract and Essential Oil from Acanthus polystachyus Delile (Acanthaceae)

The evolution of microbes in response to conventional antimicrobials leads to antimicrobial resistance (AMR) and multidrug resistance (MDR), and it is a global threat to public health. Natural products are possible solutions to this massive challenge. In this study, the potential of Acanthus polystachyus extracts was investigated for phytochemical composition and biological properties as antimicrobials. Gas chromatography-mass spectra (GC-MS) analysis of methanol extract (ME) and essential oil (EO) detected 79 and 20 compounds, respectively. The major compounds identified in ME and their abundance were β-sitosterol acetate (16.06%), cholest-5-en-3-yl (9Z)-9-octadecenoate (9.54%), 1-dodecanol (7.57%), (S)-(E)-(-)-4-acetoxy-1-phenyl-2-dodecen-1-one (6.03%), neophytadiene (5.7%), (E)-2-nonadecene (3.9%), hexanol-4-D2 (2.92%), and decane (2.4%). Most compounds have known bioactive functions. In EO, the major compounds were stearyl alcohol (25.38%); cis-9-tetradecenoic acid, isobutyl ester (22.95%); butyl 9-tetradecenoate (10.62%); 11,13-dimethyl-12-tetradecen-1-ol acetate (10.14%); ginsenol (3.48%); and diisooctyl phthalate (2.54%). All compounds are known to be bioactive. The antioxidant activity of ME and EO ranged from 48.3 to 84.2% radical scavenging activity (RSA) and 45.6 to 82% RSA, respectively, with dose dependency. The disc diffusion assay for the antimicrobial activity of ME revealed high inhibition against Acenetobacter baumannii (130.2%), Pseudomonas aeruginosa (100.3%), and Staphylococcus aureus (87.7%). The MIC, MBC/MFC, and MBIC values for ME were 0.5-1.0, 2-4, and 0.5-1.0 mg/mL and for EO were 0.31-0.62, 1.25-2.5, and 0.31-0.62 μL/mL, respectively, indicating inhibition potential as well as inhibition of biofilm formation. The tolerance test values indicated bactericidal activity against most strains and bacteriostatic/fungistatic activity against A. baumannii, E. faecalis, and C. albicans. The antiquorum sensing activity of ME achieved by pyocyanin inhibition assay on P. aeruginosa showed a 51.6% inhibition at 500 μg/mL. These results suggest that ME and EO derived from A. polystachyus leaves are potent, valuable, cost-effective antioxidants and antimicrobials. Both extracts may effectively combat pathogenic and resistant microbes.

Initial Experience with the Commercial Electron FLASH Research Extension

PURPOSE/OBJECTIVE(S)

The purpose of this study was to introduce a new commercial electron FLASH system that has the potential to become widely available for FLASH researchers globally. In this study, we first present the initial acceptance and commissioning tests for the FLASH system, and second, we highlight preliminary FLASH effect results from our cell studies.

MATERIALS/METHODS

A linear accelerator was converted into a commercial research platform with the FLASH Research Extension, enabling the generation of a powerful 16 MeV electron FLASH beam. The dosimetric and stability tests were conducted using various dosimeters (i.e., radiochromic film, optically stimulated luminescent dosimeters (OSLDs), and a plane-parallel ionization chamber). To evaluate the FLASH effect, normal and cancer cell lines were FLASH irradiated using different pulse repetition frequencies (PRF) of 18 pulses/s and 180 pulses/s.

RESULTS

The electron FLASH mode was able to generate over 1 Gy per pulse at the isocenter and a dose rate of up to 690 Gy/s near the accessory mount of the Linac gantry head. The charge collected by the plane-parallel ionization chamber at the highest PRF (i.e., 180 pulses/s) showed a linear relationship with the delivered number of pulses (i.e., 1 to 99 pulses) with a coefficient of determination (R2) of 0.9996. The absorbed dose measured using radiochromic film and OSLDs agreed within 3%, on average, and followed an inverse square law as the source-to-axis distance (SAD) varied for which the R2 values were 0.9972 and 0.9955 for radiochromic film and OSLDs, respectively. The profile of the FLASH beam was symmetrical but was not as flat as the conventional 16 MeV electron beam due to the use of a thinner custom scattering foil to reduce the degradation of the ultra-high dose rate. The depth-dose curve beyond the build-up region for the FLASH beam was similar to the conventional 16 MeV electron beam for which the range at 50% the maximum dose (R50) agreed within 0.5 mm. The FLASH beam output remained consistent over a 4-month period with a variation of 2.5%, on average. The FLASH sparing effect was observed in vitro for healthy human pancreatic cells. Furthermore, we observed that the highest PRF beam (180 pulses/s) was more effective at destroying pancreatic cancerous cells while minimizing damage to healthy cells compared to the lowest PRF beam (18 pulses/s).

CONCLUSION

The novel commercial FLASH Research Extension system was dosimetrically characterized for pre-clinical FLASH research, and preliminary in vitro results demonstrated the FLASH effect. Given the prevalence of linear accelerators, this new commercial system has the potential to greatly increase the access to FLASH research.

Equivalent Uniform Dose (EUD) and the Evaluation of Cell Survival in Spatially Fractionated Radiotherapy (SFRT)

PURPOSE/OBJECTIVE(S)

SFRT has shown promise as a treatment modality to decrease normal tissue sparing without compromising tumor coverage, i.e., an increase in the therapeutic window compared to more conventional uniform radiation therapy (RT). The aim of this work is to examine and test several alternative bio-dosimetric parameters for the prediction of cell survival for normal-tissue and tumor cell lines irradiated in vitro with uniform and microbeam radiotherapy (MRT).

MATERIALS/METHODS

A bespoke tungsten collimator with 50 parallel, 50 µm wide slits and 400 µm slit spacing was mounted into an x-ray cabinet. Human fibroblast (MRC5) and two human tumor cell lines (LN18 and A549) were irradiated with a range of doses (< 10 Gy) for uniform and MRT (50um slits, 400um center spacing) using kV X-rays. Average, mean and valley dose as useful predictive metrics of cell survival are compared to the equivalent uniform dose (EUD) with biological parameters estimated from uniform-dose experiments.

RESULTS

We find that EUD, with linear-quadratic (LQ) model parameters, is more predictive for survival after SFRT than maximum, minimum or average dose. The maximum and average doses are correlated very poorly with in vitro cell survival. The difference in cell survival between uniform and MRT irradiation as a function of EUD is cell-type and dose dependent. The report results suggest that MRT is more effective at cell killing of tumor-cell lines than uniform irradiation for both tumor cell lines. However, MRT is less effective at killing normal tissue cells than uniform irradiation.

CONCLUSION

EUD is a superior predictor of in vitro cell survival than other metrics sometimes used in the SFRT literature, including mean dose, maximum dose, and valley dose. The reported studies provide some evidence that SFRT may increase the therapeutic ratio by producing spatial dose distributions that effectively reduce normal-tissue damage with little or no change in biological damage to tumor cells. Additional studies are needed to further extend and generalize our results and to test our conclusions against a larger dose range, low and high linear energy transfer (LET) radiations and additional cell lines.

Women in trauma and orthopaedics: are we losing them at the first hurdle?

INTRODUCTION

Diversity in the healthcare workforce is associated with improved performance and patient-reported outcomes. Gender disparity in Trauma and Orthopaedics (T&O) is well recognised. The aim of this study was to compare factors that influence career choice in T&O between male and female final-year students. Furthermore, the trend of representation of women in T&O over the last decade was also compared with other surgical specialities.

METHODS

An online survey of final-year students who attended nationally advertised T&O courses over a 2-year period was conducted. Data from NHS digital was obtained to assess gender diversity in T&O compared with other surgical specialities.

RESULTS

A total of 414 students from 13 UK medical schools completed the questionnaire. Compared with male students (34.2%), a significantly higher proportion of women (65.8%) decided against a career in T&O, p<0.001. Factors that dissuaded a significantly higher percentage of women included gender bias, technical aspects of surgery, unsociable hours, on-call commitments, inadequate undergraduate training and interest in another specialty (p<0.05). Motivating factors for choosing a career in T&O were similar between both sexes. T&O was the surgical specialty with the lowest proportion of women at both consultant and trainee level over the last decade.

CONCLUSION

T&O remains an unpopular career choice among women. To enhance recruitment of women in T&O, future strategies should be directed toward medical students. Universities, orthopaedic departments and societies must work collaboratively to embed culture change, improve the delivery of the undergraduate curriculum, and facilitate students' exposure to operating theatres and female role models.

Implementation and Effectiveness Outcomes of a Quality Improvement Intervention to Strengthen the Application of the World Health Organization Surgical Safety Checklist Tool in a Limited-Resource Setting

BACKGROUND

There is a disparity in the provision of quality and safe surgical care in Nigeria. The capacity to track surgical safety through the use of the surgical safety checklist tool is variable in this setting. This study aimed to assess the outcomes of training on this checklist and the results of its pilot implementation.

SUBJECTS, MATERIALS AND METHODS

A mixed-methods research comprising of quantitative and qualitative study designs was conducted to evaluate these 23 weeks intervention in our centre. Implementation was conducted in two phases: training of the surgical team and pilot testing of the intervention. Using the RE-AIM framework, implementation outcomes evaluated included reach of training, adoption of checklist and implementation challenges, while effectiveness outcomes evaluated included change in the knowledge score after the training and self-reported impact of the training and pilot test. Quantitative and qualitative data were collected and analyzed.

RESULTS

There was a 2.4-point significant increase in the knowledge score after the training. During the pilot testing phase, 843 patients had surgery. The weekly checklist utilization rate for elective surgery rose to 64% at project completion. Despite logistic and manpower-related implementation challenges, the training intervention facilitated the translation of participant knowledge into practice (81.5%) and the pilot phase had a high impact on the practice of checklist use (3.8 ± 0.9).

CONCLUSION

The quality improvement programme enhanced knowledge of checklist use and led to improved behaviour and positive organizational change. However, barriers need to be addressed to strengthen the sustainable use of the checklist tool.

A CLINICO-EPIDEMIOLOGICAL STUDY OF MULTIPLE SCLEROSIS IN MOSUL CITY, IRAQ

Multiple Sclerosis (MS) is a debilitating disease that affects millions of people worldwide. In this study, we aimed to shed light on the clinical and epidemiological characteristics of MS in Ninevah governorate, Iraq. Our goal was to provide valuable insights into the disease's prevalence, symptoms, and functional disability among Iraqi patients. The present case-series study was conducted on 418 patients diagnosed with MS based on McDonald criteria. Kurtzke Expanded Disability Status Score (EDSS) used for patients' assessment. The prevalence of MS in Ninevah governorate is predicted to be 10.3 per 100,000, with an annual incidence ranging from 4.6 to 11.57 per million in the last four years. The average age of symptom onset was 27.7±9.9 years, with an average symptom duration of 7.2±6.9 years. Women were twice as likely to be diagnosed with MS, with a female-male ratio of 1:0.6. Sensory symptoms were more common than visual and motor symptoms. The most common subtype of clinical presentation was relapsing-remitting MS, followed by secondary progressive MS and primary progressive MS. Finally, 68.5%, 25.4%, and 6.1% of patients had mild, moderate, and severe functional disability, respectively. The study found that the age of onset, clinical pattern, and disability from MS were consistent with studies in other Middle Eastern countries. However, the prevalence of MS in the study was relatively lower than in neighboring countries due to underestimation of the disease, limited tools for diagnosing MS, and a shortage of neurologists. The study emphasizes the importance of early diagnosis and proper management of MS to improve patients' quality of life.

Application of Machine Learning Algorithms to Predict Uncontrolled Diabetes Using the All of Us Research Program Data

There is a paucity of predictive models for uncontrolled diabetes mellitus. The present study applied different machine learning algorithms on multiple patient characteristics to predict uncontrolled diabetes. Patients with diabetes above the age of 18 from the All of Us Research Program were included. Random forest, extreme gradient boost, logistic regression, and weighted ensemble model algorithms were employed. Patients who had a record of uncontrolled diabetes based on the international classification of diseases code were identified as cases. A set of features including basic demographic, biomarkers and hematological indices were included in the model. The random forest model demonstrated high performance in predicting uncontrolled diabetes, yielding an accuracy of 0.80 (95% CI: 0.79-0.81) as compared to the extreme gradient boost 0.74 (95% CI: 0.73-0.75), the logistic regression 0.64 (95% CI: 0.63-0.65) and the weighted ensemble model 0.77 (95% CI: 0.76-0.79). The maximum area under the receiver characteristics curve value was 0.77 (random forest model), while the minimum value was 0.7 (logistic regression model). Potassium levels, body weight, aspartate aminotransferase, height, and heart rate were important predictors of uncontrolled diabetes. The random forest model demonstrated a high performance in predicting uncontrolled diabetes. Serum electrolytes and physical measurements were important features in predicting uncontrolled diabetes. Machine learning techniques may be used to predict uncontrolled diabetes by incorporating these clinical characteristics.

Association of Polygenic Score and the involvement of Cholinergic and Glutamatergic Pathways with Lithium Treatment Response in Patients with Bipolar Disorder

Lithium is regarded as the first-line treatment for bipolar disorder (BD), a severe and disabling mental disorder that affects about 1% of the population worldwide. Nevertheless, lithium is not consistently effective, with only 30% of patients showing a favorable response to treatment. To provide personalized treatment options for bipolar patients, it is essential to identify prediction biomarkers such as polygenic scores. In this study, we developed a polygenic score for lithium treatment response (Li+PGS) in patients with BD. To gain further insights into lithium's possible molecular mechanism of action, we performed a genome-wide gene-based analysis. Using polygenic score modeling, via methods incorporating Bayesian regression and continuous shrinkage priors, Li+PGS was developed in the International Consortium of Lithium Genetics cohort (ConLi+Gen: N=2,367) and replicated in the combined PsyCourse (N=89) and BipoLife (N=102) studies. The associations of Li+PGS and lithium treatment response - defined in a continuous ALDA scale and a categorical outcome (good response vs. poor response) were tested using regression models, each adjusted for the covariates: age, sex, and the first four genetic principal components. Statistical significance was determined at P<����������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������������.

Patterns of Failure After Stereotactic Body Radiotherapy to Sacral Metastases

AIMS

Stereotactic body radiotherapy (SBRT) is increasingly used to treat sacral metastases. We analysed our centre's local relapse rates and patterns of failure after sacral SBRT and assessed whether using the consensus contouring recommendation (CCR) may have prevented local relapse.

MATERIALS AND METHODS

We conducted a single-centre retrospective review of patients treated with sacral SBRT between February 2012 and December 2021. The cumulative incidence of local relapse, patterns of failure and overall survival were determined. Two investigators reviewed planning computed tomography scans and imaging at relapse to determine if local relapse was potentially preventable with a larger CCR-derived radiotherapy field.

RESULTS

In total, 34 patients received sacral SBRT, with doses ranging from 24 to 40 Gy over three to five fractions. The most frequently used schedule was 30 Gy in three fractions. Common primaries treated included prostate (n = 16), breast (n = 6), lung (n = 3) and renal (n = 3) cancers. The median follow-up was 20 months (interquartile range 13-55 months). The cumulative incidence of local relapse (4/34) was 2.9% (95% confidence interval 0.2-13.2), 6.3% (95% confidence interval 1.1-18.5) and 16.8% (95% confidence interval 4.7-35.4) at 6 months, 1 year and 2 years, respectively. The patterns of failure were local-only (1/34), local and distant (3/34) and distant relapse (10/34). The overall survival was 96.7% (95% confidence interval 90.5-100) and 90.6% (95% confidence interval 78.6-100) at 1 and 2 years, respectively. For prostate/breast primaries, the cumulative incidence of local relapse was 4.5% (95% confidence interval 0.3-19.4), 4.5% (95% confidence interval 0.3-19.4) and 12.5% (95% confidence interval 1.7-34.8) at 6 months, 1 and 2 years, respectively. Twenty-nine cases (85.3%) deviated from the CCR. Sacral relapse was potentially preventable if the CCR was used in one patient (2.9% of the whole cohort and 25% of the relapsed cohort).

DISCUSSION

We have shown excellent local control rates with sacral SBRT, which was largely planned with a margin expansion approach.

Lifestyle, genetic risk and incidence of cancer: a prospective cohort study of 13 cancer types

BACKGROUND

Genetic and lifestyle factors are associated with cancer risk. We investigated the benefits of adhering to lifestyle advice by the World Cancer Research Fund (WCRF) with the risk of 13 types of cancer and whether these associations differ according to genetic risk using data from the UK Biobank.

METHODS

In 2006-2010, participants aged 37-73 years had their lifestyle assessed and were followed up for incident cancers until 2015-2019. Analyses were restricted to those of White European ancestry with no prior history of malignant cancer (n = 195 822). Polygenic risk scores (PRSs) were computed for 13 cancer types and these cancers combined ('overall cancer'), and a lifestyle index was calculated from WCRF recommendations. Associations with cancer incidence were estimated using Cox regression, adjusting for relevant confounders. Additive and multiplicative interactions between lifestyle index and PRSs were assessed.

RESULTS

There were 15 240 incident cancers during the 1 926 987 person-years of follow-up (median follow-up = 10.2 years). After adjusting for confounders, the lifestyle index was associated with a lower risk of overall cancer [hazard ratio per standard deviation increase (95% CI) = 0.89 (0.87, 0.90)] and of eight specific cancer types. There was no evidence of interactions on the multiplicative scale. There was evidence of additive interactions in risks for colorectal, breast, pancreatic, lung and bladder cancers, such that the recommended lifestyle was associated with greater change in absolute risk for persons at higher genetic risk (P < 0.0003 for all).

CONCLUSIONS

The recommended lifestyle has beneficial associations with most cancers. In terms of absolute risk, the protective association is greater for higher genetic risk groups for some cancers. These findings have important implications for persons most genetically predisposed to those cancers and for targeted strategies for cancer prevention.

Multifactorial structure of cognitive assessment tests in the UK Biobank: A combined exploratory factor and structural equation modeling analyses

Introduction

The UK Biobank cognitive assessment data has been a significant resource for researchers looking to investigate predictors and modifiers of cognitive abilities and associated health outcomes in the general population. Given the diverse nature of this data, researchers use different approaches - from the use of a single test to composing the general intelligence score, g, across the tests. We argue that both approaches are suboptimal - one being too specific and the other one too general - and suggest a novel multifactorial solution to represent cognitive abilities.

Methods

Using a combined Exploratory Factor (EFA) and Exploratory Structural Equation Modeling Analyses (ESEM) we developed a three-factor model to characterize an underlying structure of nine cognitive tests selected from the UK Biobank using a Cattell-Horn-Carroll framework. We first estimated a series of probable factor solutions using the maximum likelihood method of extraction. The best solution for the EFA-defined factor structure was then tested using the ESEM approach with the aim of confirming or disconfirming the decisions made.

Results

We determined that a three-factor model fits the UK Biobank cognitive assessment data best. Two of the three factors can be assigned to fluid reasoning (Gf) with a clear distinction between visuospatial reasoning and verbal-analytical reasoning. The third factor was identified as a processing speed (Gs) factor.

Discussion

This study characterizes cognitive assessment data in the UK Biobank and delivers an alternative view on its underlying structure, suggesting that the three factor model provides a more granular solution than g that can further be applied to study different facets of cognitive functioning in relation to health outcomes and to further progress examination of its biological underpinnings.

Metabolic profile predicts incident cancer: A large-scale population study in the UK Biobank

BACKGROUND AND AIMS

Analyses to predict the risk of cancer typically focus on single biomarkers, which do not capture their complex interrelations. We hypothesized that the use of metabolic profiles may provide new insights into cancer prediction.

METHODS

We used information from 290,888 UK Biobank participants aged 37 to 73 years at baseline. Metabolic subgroups were defined based on clustering of biochemical data using an artificial neural network approach and examined for their association with incident cancers identified through linkage to cancer registry. In addition, we evaluated associations between 38 individual biomarkers and cancer risk.

RESULTS

In total, 21,973 individuals developed cancer during the follow-up (median 3.87 years, interquartile range [IQR] = 2.03-5.58). Compared to the metabolically favorable subgroup (IV), subgroup III (defined as "high BMI, C-reactive protein & cystatin C") was associated with a higher risk of obesity-related cancers (hazard ratio [HR] = 1.26, 95 % CI = 1.21 to 1.32) and hematologic-malignancies (e.g., lymphoid leukemia: HR = 1.83, 95%CI = 1.44 to 2.33). Subgroup II ("high triglycerides & liver enzymes") was strongly associated with liver cancer risk (HR = 5.70, 95%CI = 3.57 to 9.11). Analysis of individual biomarkers showed a positive association between testosterone and greater risks of hormone-sensitive cancers (HR per SD higher = 1.32, 95%CI = 1.23 to 1.44), and liver cancer (HR = 2.49, 95%CI =1.47 to 4.24). Many liver tests were individually associated with a greater risk of liver cancer with the strongest association observed for gamma-glutamyl transferase (HR = 2.40, 95%CI = 2.19 to 2.65).

CONCLUSIONS

Metabolic profile in middle-to-older age can predict cancer incidence, in particular risk of obesity-related cancer, hematologic malignancies, and liver cancer. Elevated values from liver tests are strong predictors for later risk of liver cancer.

Efficacy of Ethanol Extract of Botanicals in Controlling Wheat Blast Fungus Magnaporthe oryzae triticum in vitro

The present research work was conducted to evaluate the efficacy of eight fresh botanicals namely Azadirachta indica (Neem leaf), Allium cepa (Onion bulb), Allium sativum (Garlic), Curcuma longa (Turmeric), Zingiber officinale (Ginger), Allamanda cathartica (Allamanda leaf), Nigella sativa (Black cumin) and Aloe vera (Aloe vera) against Magnaporthe oryzae triticum (MoT) and solvent, ethanol (95%) was used for the phytochemical extraction of various plant parts. Three concentrations namely 1:1 (w/v), 1:0.50 (w/v) and 1:0.25 (w/v) of plant parts and ethanol were used for botanical extraction. The antifungal activity of botanicals against a virulent MoT isolate CHMoT07 was evaluated in-vitro using poison food technique. The lowest mycelia growth was recorded with Aloe vera (Aloe vera leaf) extracts and Nigella sativa (Black cumin seeds) extracts @ 1:1 w/v and @ 1:0.25 w/v with growth rate of 3.00 mm and 3.33 mm respectively at 7 days after inoculation, whereas the highest mycelia growth rate of MoT isolates was recorded in control plates both at 7 DAI and 14 DAI under in-vitro condition.

329 ANTICHOLINERGIC BURDEN IN PEOPLE LIVING WITH DEMENTIA ATTENDING GERIATRIC MEDICINE AND PSYCHIATRY FOR OLDER PERSONS SERVICES

Background

Anticholinergic burden is associated with an increase in cognitive decline, delirium and confusion. We aimed to examine the Anticholinergic Cognitive Burden (ACB) of patients referred to local dementia services, and the prescribing of acetylcholinesterase inhibitors in patients with a significant anticholinergic burden. We also looked at frequency of prescribing of classes of some medications known to increase anticholinergic burden.

Methods

A retrospective chart review was carried out of new referrals attending local Geriatric Medicine and/or Psychiatry For Older Persons outpatient services with a diagnosis of dementia between 2017 and 2018. Medications in use at the time of patient review were obtained. ACB was calculated using ACB score. Results were analysed descriptively.

Results

163 patients over 65 years old were included in this study, 94 (57.6%) were female. 30% (N = 49) had a significant anticholinergic burden (ACB &gt;3). The mean ACB was 1.69 (Range 0 – 8). 38% of all patients (N = 63) were prescribed an acetylcholinesterase inhibitor, and of those, 20% (N = 13) had a significant anticholinergic burden. Polypharmacy (use of 5 medications or more) was evident with 76% (N = 124) patients. Regarding groups of medications known to increase ACB, 35.5% (N = 58) were prescribed antipsychotics and 18.4% (30) were prescribed benzodiazepines.

Conclusion

There is a significant anticholinergic burden among people living with dementia attending the geriatric medicine and psychiatry of later life services. Some patients with a significant anticholinergic burden were being prescribed acetylcholinesterase inhibitors. This suggests acetylcholinesterase inhibitors may be prescribed without also discontinuing inappropriate medications that are contributing to the anticholinergic burden. We should look to further reduce the anticholinergic burden of patients attending the dementia services by avoiding these medications or using alternatives where available.

977 Breaking Out of Tradition: Designing Escape Rooms as Novel Simulation

Aim

The emerging field of gamification, the addition of game play elements to non-game settings, is widely used in business and is increasingly being used in education. Successful methods have included live leader boards and a web-based game solving a protein folding conundrum.

Method

We designed an escape room (ER), incorporating gaming elements, focussing on communication in a surgical environment. A cross over study was delivered to 4th year medical students, comparing traditional simulation. The ER included logic puzzles, hidden clues, padlocked boxes, and surgical skills appropriate to their level. Self-reported engagement and teamwork were recorded, as was observed teamwork and communication skills.

Results

Self-reported engagement was very high for the students compared to more traditional simulation, including better understanding of effective communication strategies. The ER group were less likely to self-identify learning points but structured debrief mitigated this difference.

Conclusions

Gamification techniques can be integrated with good engagement and educational outcomes and should be considered as an adjunct to existing simulation strategy.

775 Role of Inversion Imaging in the Diagnoses of Neck of Femur Fractures

Aim

The objective of this study was to assess whether inversion of grey scale radiograph images has any impact on the diagnostic sensitivity and inter-observer reliability in diagnosing neck of femur fractures.

Method

We performed a retrospective, single centre study, using 50 randomly selected AP pelvis radiographs. The images included a combination of normal, intracapsular and extracapsular neck of femur fractures, which had been confirmed on CT, MRI and/or subsequent surgery.

Four independent observers (two orthopaedic specialists, one registrar and one SHO in orthopaedics) reviewed the images and graded each radiograph image using the Likert scale in response to the statement “there is a fracture”. Following this, the same radiographs were inverted to grey scale images and sent for a second review using the same method. RAND correlation was used for statistical analysis.

Results

Overall, observers appeared to have similar accuracy and equivocal rates with normal and inversion radiographic imaging.

One of the T&O Consultant's had much higher equivocal rate when analysing inverted radiographs compared to conventional digital radiographs but had slightly higher accuracy with inversion (95.35% compared to 93.88%) as well as the Registrar (83.33% compared to 81.63%). The second Trauma and Orthopaedics Consultant had slightly more accuracy with conventional digital radiographs (89.58% compared with 87.50%).

Conclusions

Inversion of digital radiographs did not affect the diagnostic sensitivity of neck of femur fractures in our study, and similarly did to not have a statistically significant impact in clinician confidence in diagnosing neck of femur fractures.

971 Gamification of Education; Can Playable Education Result in Better Learning Outcomes?

Aim

Combining traditional simulation (TS) and the emerging field of gamification, to create medical Escape Rooms (ERS) has been used in Nursing to good results but is yet to be widely adopted in medical education. We conducted a pilot study to create ERS for undergraduates to assess their educational value.

Method

Existing Simulation themes of sepsis, post-operative bleeding, trauma, burns and communication in the theatre environment were developed into Escape Rooms by a multidisciplinary team. A cross over study for 4th year students was carried out. Questionnaires were used to evaluate the experience, learning assessed by pre and post quiz and observational tools for teamwork, communication and leadership were utilised.

Results

Qualitative data demonstrated overall good feedback on enjoyment an engagement. Quantitative data collected as pre- and post-exposure learning demonstrated equivocal benefit. Self-assessed teamwork showed equal in all domains and improved in contribution of knowledge and maintaining team focus on the ER group.

Conclusions

Participants find ER enjoyable have similar educational benefits of traditional simulation with the benefits on enhancing non-technical skills amongst a novice group. Escape rooms may be useful as an adjunct to TS particularly at developing non-technical skills.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Quantitative systems pharmacology modeling sheds light into the dose response relationship of a trispecific T cell engager in multiple myeloma

In relapsed and refractory multiple myeloma (RRMM), there are few treatment options once patients progress from the established standard of care. Several bispecific T-cell engagers (TCE) are in clinical development for multiple myeloma (MM), designed to promote T-cell activation and tumor killing by binding a T-cell receptor and a myeloma target. In this study we employ both computational and experimental tools to investigate how a novel trispecific TCE improves activation, proliferation, and cytolytic activity of T-cells against MM cells. In addition to binding CD3 on T-cells and CD38 on tumor cells, the trispecific binds CD28, which serves as both co-stimulation for T-cell activation and an additional tumor target. We have established a robust rule-based quantitative systems pharmacology (QSP) model trained against T-cell activation, cytotoxicity, and cytokine data, and used it to gain insight into the complex dose response of this drug. We predict that CD3-CD28-CD38 killing capacity increases rapidly in low dose levels, and with higher doses, killing plateaus rather than following the bell-shaped curve typical of bispecific TCEs. We further predict that dose–response curves are driven by the ability of tumor cells to form synapses with activated T-cells. When competition between cells limits tumor engagement with active T-cells, response to therapy may be diminished. We finally suggest a metric related to drug efficacy in our analysis—“effective” receptor occupancy, or the proportion of receptors engaged in synapses. Overall, this study predicts that the CD28 arm on the trispecific antibody improves efficacy, and identifies metrics to inform potency of novel TCEs.

Considering hormone-sensitive cancers as a single disease in the UK biobank reveals shared aetiology

Hormone-related cancers, including cancers of the breast, prostate, ovaries, uterine, and thyroid, globally contribute to the majority of cancer incidence. We hypothesize that hormone-sensitive cancers share common genetic risk factors that have rarely been investigated by previous genomic studies of site-specific cancers. Here, we show that considering hormone-sensitive cancers as a single disease in the UK Biobank reveals shared genetic aetiology. We observe that a significant proportion of variance in disease liability is explained by the genome-wide single nucleotide polymorphisms (SNPs), i.e., SNP-based heritability on the liability scale is estimated as 10.06% (SE 0.70%). Moreover, we find 55 genome-wide significant SNPs for the disease, using a genome-wide association study. Pair-wise analysis also estimates positive genetic correlations between some pairs of hormone-sensitive cancers although they are not statistically significant. Our finding suggests that heritable genetic factors may be a key driver in the mechanism of carcinogenesis shared by hormone-sensitive cancers.

OP0077 SYNOVIAL RNA-SEQ ANALYSIS OF THE R4RA TRIAL IDENTIFIES SIGNATURES OF TREATMENT RESISTANCE AND REFRACTORY STATE IN RHEUMATOID ARTHRITIS

Background

Although up to 5-20% of rheumatoid arthritis (RA) patients do not respond to all current medications including biologic therapies, relatively little is known about the underlying pathogenic mechanisms driving non-response. In the first biopsy-driven randomized clinical trial in RA (R4RA)1, patients, in whom synthetic-DMARDs and at least one anti-TNF drug were not effective, were randomised 1:1 to rituximab (RTX) or tocilizumab (TOC) with a balanced stratification based on their synovial B-cell rich/poor signature, and response was assessed at 16 weeks. Non-responders were subsequently allowed to switch to the alternative drug with 48-week follow-up.

Objectives

Investigate mechanisms of response and non-response to RTX and TOC through deep molecular (RNA-Sequencing) profiling of synovial tissue.

Methods

RNA-Seq from baseline synovial tissue biopsies of patients who received RTX (n=88) or TOC (n=94) at any point in the trial was analysed for differentially expressed genes and associated modules between responders and non-responders. Response was defined as 50% improvement in clinical disease activity index (CDAI) score. Patients who had received both drugs during the trial were subdivided into RTX only responders (pro-RTX, n=9), TOC only responders (pro-TOC, n=12) and refractory patients (no response to both RTX & TOC, n=32) and analysed for differential gene expression and performed gene module analysis.

Results

6625 genes were significantly differentially expressed between RTX responders compared to non-responders, with a predominance of antigen presentation as well as T- and B-cell genes being associated with response, while non-response was linked to fibroblast associated genes. Comparison between TOC responders and non-responders identified fewer (85) differentially expressed genes, however lymphocyte and immunoglobulin genes were also high in the synovial tissue of TOC responders similar to RTX responders, while non-responder genes and modules also included a fibroblast signature.

The cross-over study design enabled comparison of rituximab-specific responders (pro-RTX), tocilizumab-specific responders (pro-TOC) and refractory patients (non-responders to both RTX & TOC, n=32) in a 3-way analysis (see Figure 1). This identified 1980 genes upregulated both in pro-RTX and pro-TOC patients, 175 genes exclusive to the pro-RTX group and 306 to the pro-TOC group, while 1277 genes were exclusive to the refractory group. While leukocyte modules and genes dominated RTX & TOC response, the refractory state was strongly associated with fibroblast genes and modules. We confirmed the observed expansion of fibroblasts from the RNA-Seq data by immunohistochemistry showing the presence of DKK3+ sublining fibroblasts in refractory rather than responder patients.

Conclusion

We provide novel insights into the cellular and molecular pathways underpinning multi-biologic resistance that define a refractory RA phenotype, characterised by a stromal/fibroblast signature.

References

[1]Humby, F., et al. Lancet (2021)

Acknowledgements

We would like to thank all patients and the R4RA recruiting centres and principal investigators http://www.r4ra-nihr.whri.qmul.ac.uk/recruiting_centres.php We would also like to acknowledge the UK National Institute of Health Research for funding the R4RA trial (grant reference: 11/100/76) and Versus Arthritis for providing infrastructure support through the Experimental Arthritis Treatment Centre (grant number: 20022).

Disclosure of Interests

None declared.