POS0573 MUSCULOSKELEATAL ULTRASOUND STUDIES ARE CRITICAL FOR DETECTING SERONEGATIVE INFLAMMATORY ARTHRITIS

Background

The autoantibody status of rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibodies (anti-CCP Ab) has gained widespread recognition for its role in the diagnosis of rheumatoid arthritis (RA) based on the latest diagnostic criteria for RA.1 However, in early disease, the rates of antibody expression have been reported as low as 50%2, rendering early diagnosis of RA difficult. Furthermore, the nature of seronegative rheumatoid arthritis is unknown, though it is presumed to have less aggressive disease course as compared to its seropositive counterparts. Musculoskeletal (MS) ultrasound studies have been widely used in recent clinical practice to assess soft-tissue abnormalities of the joints and disease states in RA, such as synovitis and bone erosions. MS ultrasound studies were recently shown to be more sensitive to detect early synovial changes and erosions than other radiographic methods while maintaining cost-effectiveness.3-5 We hypothesize that MS ultrasound studies are more sensitive to detecting inflammatory changes in seronegative inflammatory arthritis, which is often subclinical in presentation.

Objectives

To assess the role of MS ultrasound studies in detecting early inflammatory changes in the joints and diagnosing seronegative inflammatory arthritis.

Methods

A retrospective electronic medical record review was performed of all patients at the two University at Buffalo rheumatology clinics who underwent MS ultrasound studies after complaining of multiple joint pain. All these patients were previously seen and evaluated by at least one other medical provider, who found no evidence of inflammatory arthritis on physical examination. These patients did not meet diagnostic criteria for rheumatoid arthritis due to a lack of gross joint swelling and/or positive serological makeup. As part of their clinical care, they were referred to obtain MS ultrasound studies to rule out inflammatory arthritis. All patients were de-identified at initial data collection. Information pertaining to the patients’ 1) demographics (gender, age, ethnicity, etc.), 2) findings of MS ultrasound studies, and 3) serological studies (RF, anti-CCP Ab, HLA-B27) was collected and tabulated.

Results

Of the 363 patients who underwent MS ultrasound studies, 280 of them (77.1%) of them were found to have synovial hypertrophy [minimal = 23%, mild = 46%, moderate = 29%, severe = 2%] in bilateral MCP, PIP, carpal, and/or MTP joints, therefore conferring a diagnosis of inflammatory arthritis. The average age of these 280 patients was 48.35 ± 14.86 years old at the time of diagnosis, with female to male ratio of 4.38:1. Surprisingly, of these 280 patients with evidence of inflammatory arthritis, 69 (24.6%) of them were found to have joint erosions with either MCP or MTP joints, supporting a diagnosis of advanced inflammatory arthritis with erosive disease. The erosions were predominantly located in MTP joints (77.1%) as compared to MCP joints (22.9%). Therefore, our findings clearly demonstrated distinct clinical and ultrasonography features of seronegative inflammatory arthritis (SNIA) as compared to seropositive RA.

Conclusion

MS ultrasound studies are more sensitive to and critical for detecting inflammatory changes and joint damages in SNIA due to its subclinical presentation. Based on our findings, SN IA is underdiagnosed in individuals who complain of joint pain without gross synovitis. SNIA also likely has distinct pathophysiology that needs further characterization.

References

[1]Aydin, S.Z. et al. Eur J Rheumatol. 2017; 4(2):118-121.

[2]Barra, L. et al. J of Rheum 2014;41(12):2361-2369.

[3]Mathiessen, A. et al. Ann Rheum Dis 2017:72;51-56.

[4]Tamas, M.M. et al. Rheumatol (Oxford) 2014; 53(6):1100-1107.

[5]Salaffi, F. et al. Clin Exp Rheumatol 2014;32.1(80):S85-S90.

Disclosure of Interests

Clarice Lin: None declared, Richard Chou Consultant of: Sun Pharmaceuticals Industries Limited.

Needlestick injuries in radiology: prevention and management

Needlestick injuries are common and often underreported in invasive radiological procedures. Prior needlestick injuries have been reported in 86-91% of interventional radiologists, and on average, one needlestick injury occurs for every 5 years of practice. Of those that have had a needlestick injury, only 58% had formal education on needlestick injury prevention. Needlestick injuries can often result in long-term debility if not properly managed. Injuries can result in transmission of blood-borne pathogens, such as hepatitis B, hepatitis C, and human immunodeficiency virus. Preventative measures, such as vaccination, proper sharps selection, handling, and disposal during radiological procedures, minimising procedure time, and team communication, can decrease the risk of needlestick injuries and pathogen transmission rate. Initial management involves proper cleaning of the wound and activating the injury reporting system. Further lab testing and post-exposure prophylaxis will depend on the serology status of the source and exposed patient. Needlestick injuries with pathogen transmission can result in long-term health issues and psychological damage, therefore, it is imperative for radiologists to understand factors that increase the risk for transmission, methods to prevent injury, and how to manage an injury when it occurs.

Social determinants of health influence disease activity and functional disability in Polyarticular Juvenile Idiopathic Arthritis

BACKGROUND

Social determinants of health (SDH) greatly influence outcomes during the first year of treatment in rheumatoid arthritis, a disease similar to polyarticular juvenile idiopathic arthritis (pJIA). We investigated the correlation of community poverty level and other SDH with the persistence of moderate to severe disease activity and functional disability over the first year of treatment in pJIA patients enrolled in the Childhood Arthritis and Rheumatology Research Alliance Registry.

METHODS

In this cohort study, unadjusted and adjusted generalized linear mixed effects models analyzed the effect of community poverty and other SDH on disease activity, using the clinical Juvenile Arthritis Disease Activity Score-10, and disability, using the Child Health Assessment Questionnaire, measured at baseline, 6, and 12 months.

RESULTS

One thousand six hundred eighty-four patients were identified. High community poverty (≥20% living below the federal poverty level) was associated with increased odds of functional disability (OR 1.82, 95% CI 1.28-2.60) but was not statistically significant after adjustment (aOR 1.23, 95% CI 0.81-1.86) and was not associated with increased disease activity. Non-white race/ethnicity was associated with higher disease activity (aOR 2.48, 95% CI: 1.41-4.36). Lower self-reported household income was associated with higher disease activity and persistent functional disability. Public insurance (aOR 1.56, 95% CI 1.06-2.29) and low family education (aOR 1.89, 95% CI 1.14-3.12) was associated with persistent functional disability.

CONCLUSION

High community poverty level was associated with persistent functional disability in unadjusted analysis but not with persistent moderate to high disease activity. Race/ethnicity and other SDH were associated with persistent disease activity and functional disability.

Activated Epithelial FGF8 Signaling Induces Fused Supernumerary Incisors

FGF8, which is specifically expressed in the dental epithelium prior to the E12.5 bud stage, is a key player during odontogenesis, being responsible for the initiation of tooth development. Here, to investigate the impact of persistent FGF8 signaling on tooth development, we forcibly activated FGF8 signaling in the dental epithelium after the bud stage by generating K14-Cre;R26R-Fg8 mice. We found that a unique type of fused supernumerary incisors is formed, although morphologically resembling the features of type II dens invaginatus in humans. Further analysis revealed that ectopically activated epithelial FGF8 alters the cell fate of the incisor lingual outer enamel epithelium, endowing it with odontogenic potential by the activation of several key tooth genes, including Pitx2, Sox2, Lef-1, p38, and Erk1/2, and induces de novo formation of an extra incisor crown lingually in parallel to the original one, leading to the formation of an extra incisor crown and fused with the original incisor eventually. Meanwhile, the overdosed epithelial FGF8 signaling dramatically downregulates the expression of mesenchymal Bmp4, leading to severely impaired enamel mineralization. Based on the location of the extra incisors, we propose that they are likely to be rescued replacement teeth. Our results further demonstrate the essential role of FGF8 signaling for tooth initiation and the establishment of progenitor cells of dental epithelial stem cells during development.

[Exendin-4 promotes autophagy to relieve lipid deposition in a NAFLD cell model by activating AKT/mTOR signaling pathway]

OBJECTIVE

To investigate the effect of exendin-4 on lipid deposition in hepatocytes and explore its possible mechanism for treatment of nonalcoholic fatty liver disease (NAFLD).

METHODS

Human normal hepatocyte line LO2 and hepatoma cell line HepG2 were treated with palmitic acid (PA) to mimic hepatocyte steatosis or with combined treatments with PA+exendin-4 or PA+exendin-4+3BDO. Lipid deposition and proliferation of the two cell lines following treatment with PA or PA+exendin-4 were detected using Oil Red O staining and CCK8 assay, and the expression of p-mTOR, m-TOR, p-AKT, AKT and autophagy-related proteins LC3-Ⅰ/Ⅱ and p62 were detected with Western blotting; the expression of GLP-1R was detected with both Western blotting and immunofluorescence assay. The expression of LC3-Ⅰ/Ⅱ and p62 in the cells following treatment with PA+exendin-4 and PA+exendin-4+3BDO was detected with Western blotting.

RESULTS

Lipid deposition in the two cell lines increased significantly after PA treatment, but was alleviated by co-treatment with exendin-4. PA treatment significantly inhibited the proliferation of the two cell lines (P < 0.01), and this inhibitory effect was obviously attenuated by exendin-4 (P < 0.05). Immunofluorescence assay showed that both LO2 and HepG2 cells expressed GLP-1R. The expression of p-mTOR was significantly lower and that of p-AKT was higher in cells treated with PA+exendin-4 than in PA-treated cells. Exendin-4 also down-regulated the autophagy-associated protein p62 and up-regulated the expression of LC3-Ⅱ in PA-treated cells, and this effect was obviously reversed by 3BDO.

CONCLUSION

Exendin-4 may activate the AKT-mTOR signal pathway to promote autophagy via its direct action on GLP-1R. Exendin-4 can also alleviate lipid deposition and promote proliferation of PA-treated hepatocytes, suggesting its important role in PA-induced lipid deposition in hepatocytes.

[Research advances on the effects and mechanism of curcumin in promoting diabetic wound healing]

Diabetic wound is a common complication of diabetes, and the effect of current treatment is still poor. Curcumin has many pharmacological effects, such as anti-inflammatory, anti-oxidation, antimicrobial, anti-cancer, and improving insulin resistance. In this paper, the research advances on the effects and mechanism of curcumin in promoting diabetic wound healing were mainly reviewed.

Study of the K_{L}→π^{0}νν[over ¯] Decay at the J-PARC KOTO Experiment

The rare decay K_{L}→π^{0}νν[over ¯] was studied with the dataset taken at the J-PARC KOTO experiment in 2016, 2017, and 2018. With a single event sensitivity of (7.20±0.05_{stat}±0.66_{syst})×10^{-10}, three candidate events were observed in the signal region. After unveiling them, contaminations from K^{±} and scattered K_{L} decays were studied, and the total number of background events was estimated to be 1.22±0.26. We conclude that the number of observed events is statistically consistent with the background expectation. For this dataset, we set an upper limit of 4.9×10^{-9} on the branching fraction of K_{L}→π^{0}νν[over ¯] at the 90% confidence level.

Humanized COVID-19 decoy antibody effectively blocks viral entry and prevents SARS-CoV-2 infection

To circumvent the devastating pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, a humanized decoy antibody (ACE2-Fc fusion protein) was designed to target the interaction between viral spike protein and its cellular receptor, angiotensin-converting enzyme 2 (ACE2). First, we demonstrated that ACE2-Fc could specifically abrogate virus replication by blocking the entry of SARS-CoV-2 spike-expressing pseudotyped virus into both ACE2-expressing lung cells and lung organoids. The impairment of viral entry was not affected by virus variants, since efficient inhibition was also observed in six SARS-CoV-2 clinical strains, including the D614G variants which have been shown to exhibit increased infectivity. The preservation of peptidase activity also enables ACE2-Fc to reduce the angiotensin II-mediated cytokine cascade. Furthermore, this Fc domain of ACE2-Fc was shown to activate NK cell degranulation after co-incubation with Spike-expressing H1975 cells. These promising characteristics potentiate the therapeutic prospects of ACE2-Fc as an effective treatment for COVID-19.

Blockade of BK channels attenuates chronic visceral hypersensitivity in an IBS-like rat model

BACKGROUND

Visceral hypersensitivity in irritable bowel syndrome (IBS) is still poorly understood, despite that chronic abdominal pain is the most common symptoms in IBS patients. To study effects of BK channels on visceral hypersensitivity in IBS rats and the underlying mechanisms, IBS rats were established by colorectal distention (CRD) in postnatal rats. The expression of large-conductance calcium and voltage-dependent potassium ion channels (BK channels) of the thoracolumbar spinal cord was examined in IBS and control rats. The effects of BK channel blockade on visceral hypersensitivity were evaluated. The interaction of BK channels and N-methyl-D-aspartate acid (NMDA) receptors was explored, and synaptic transmission at superficial dorsal horn (SDH) neurons of the thoracolumbar spinal cord was recorded by whole-cell patch clamp in IBS rats.

RESULTS

The expression of the BK channels of the thoracolumbar spinal cord in IBS rats was significantly reduced. The blockade of BK channels could reduce the visceral hypersensitivity in IBS rats. There was an interaction between BK channels and NMDA receptors in the spinal cord. The frequency of spontaneous inhibitory postsynaptic currents (sIPSCs) in SDH neurons is significantly reduced in IBS rats. The blockade of BK channels depolarizes the inhibitory interneuron membrane and increases their excitability in IBS rats.

CONCLUSIONS

BK channels could interact with NMDA receptors in the thoracolumbar spinal cord of rats and regulate visceral hypersensitivity in IBS rats.

Reducing scan time of paediatric 99mTc-DMSA SPECT via deep learning

AIM

To investigate the feasibility of reducing the scan time of paediatric technetium 99m (^99mTc) dimercaptosuccinic acid (DMSA) single-photon-emission computed tomographic (SPECT) using a deep learning (DL) method.

MATERIAL AND METHODS

A total of 112 paediatric ^99mTc-DMSA renal SPECT scans were analysed retrospectively. Of the 112 examinations, 88 (84 for training and four for validation) were used to train a DL-based model that could generate full-acquisition-time reconstructed SPECT images from half-time acquisition. The remaining 24 examinations were used to evaluate the performance of the trained model.

RESULTS

DL-based SPECT images obtained from half-time acquisition have image quality similar to the standard clinical SPECT images obtained from full-acquisition-time acquisition. Moreover, the accuracy, sensitivity and specificity of the DL-based SPECT images for detection of affected kidneys were 91.7%, 83.3%, and 100%, respectively.

CONCLUSION

These preliminary results suggest that DL has the potential to reduce the scan time of paediatric ^99mTc-DMSA SPECT imaging while maintaining diagnostic accuracy.

Toward High Precision XCO2 Retrievals From TanSat Observations: Retrieval Improvement and Validation Against TCCON Measurements

TanSat is the 1st Chinese carbon dioxide (CO2) measurement satellite, launched in 2016. In this study, the University of Leicester Full Physics (UoL-FP) algorithm is implemented for TanSat nadir mode XCO2 retrievals. We develop a spectrum correction method to reduce the retrieval errors by the online fitting of an 8th order Fourier series. The spectrum-correction model and its a priori parameters are developed by analyzing the solar calibration measurement. This correction provides a significant improvement to the O2 A band retrieval. Accordingly, we extend the previous TanSat single CO2 weak band retrieval to a combined O2 A and CO2 weak band retrieval. A Genetic Algorithm (GA) has been applied to determine the threshold values of post-screening filters. In total, 18.3% of the retrieved data is identified as high quality compared to the original measurements. The same quality control parameters have been used in a footprint independent multiple linear regression bias correction due to the strong correlation with the XCO2 retrieval error. Twenty sites of the Total Column Carbon Observing Network (TCCON) have been selected to validate our new approach for the TanSat XCO2 retrieval. We show that our new approach produces a significant improvement on the XCO2 retrieval accuracy and precision when compared to TCCON with an average bias and RMSE of -0.08 ppm and 1.47 ppm, respectively. The methods used in this study can help to improve the XCO2 retrieval from TanSat and subsequently the Level-2 data production, and hence will be applied in the TanSat operational XCO2 processing.

Phase states, microstructure and dielectric characteristics of solid solutions (1 - x)NaNbO3 - xCa2Nb2O7 and (1 - x)NaNbO3 - xSr2Nb2O7

Ceramics of binary systems solid solutions (1 – x)NaNbO₃ – xCa₂Nb₂O₇ and (1 – x)NaNbO₃ – xSr₂Nb₂O₇ with non-isostructural extreme components were prepared by the solid-phase reactions technique with the following sintering using conventional ceramic technology. It was found that ceramics with x ≤ 0.2 have a perovskite structure. Layered type of structure predominates in the concentration range 0.2 < x ≤ 1. Phase diagrams of both systems at room temperature have been determined in the perovskite area. It was shown that this area contains two concentration regions with the different crystal structures and the morphotropic phase boundary between them. Microstructure and dielectric characteristics of selected solid solutions were investigated. The influence of technological regulations, such as mechanical activation and variation of sintering temperatures, on the formation of the microstructure and dielectric characteristics was studied for the individually selected concentrations (x = 0.1 and x = 0.25). Dielectric characteristics of ceramics revealed the presence of the Maxwell-Wagner polarization and its corresponding relaxation in the solid solutions (1 – x)NaNbO₃ – xCa₂Nb₂O₇ at x > 0.20.