Near-miss Thoracic Spine Solitary Plasmacytoma with Neurological Deficit during Pregnancy: A Case Report

Solitary plasmacytoma (SPC) account for only 5% of plasma cell neoplasms, and the literature hardly reports spinal SPC with a neurological deficit. Furthermore, spinal surgical intervention during pregnancy is rarely encountered and often requires multidisciplinary collaboration and management. The objective of this case report is to highlight this near-miss diagnosis and spinal surgical intervention during pregnancy. A 31-year-old woman with 24 weeks gestation presented with sudden paralysis and incontinence, with an underlying history of chronic backpain over a two-month period. Initially, she was treated for musculoskeletal back pain by obstetric colleagues during an antenatal visit, and no radiograph was performed. A non-contrasted spinal MRI was eventually requested when she started to show bilateral lower limb weakness, numbness and incontinence. The MRI highlighted thoracic vertebrae T11 vertebra plana with kyphotic deformity and a paraspinal soft tissue mass compressing the spinal cord causing spinal cord oedema. Our initial working diagnosis was spinal tuberculosis (TB), considering TB is highly endemic in Malaysia. However, TB workup was negative, and we proceeded with spinal surgery and transpedicular biopsy. Neurology improved significantly after surgery. Eventually, serum protein electrophoresis reported plasma dyscrasia, and HPE confirmed plasmacytoma. The patient was referred to a haematologist for steroidal and chemotherapy treatment.

Harnessing lipid signaling pathways to target specialized pro-angiogenic neutrophil subsets for regenerative immunotherapy

To gain insights into neutrophil heterogeneity dynamics in the context of sterile inflammation and wound healing, we performed a pseudotime analysis of single-cell flow cytometry data using the spanning-tree progression analysis of density-normalized events algorithm. This enables us to view neutrophil transitional subsets along a pseudotime trajectory and identify distinct VEGFR1, VEGFR2, and CXCR4 high-expressing pro-angiogenic neutrophils. While the proresolving lipid mediator aspirin-triggered resolvin D1 (AT-RvD1) has a known ability to limit neutrophil infiltration, our analysis uncovers a mode of action in which AT-RvD1 leads to inflammation resolution through the selective reprogramming toward a therapeutic neutrophil subset. This accumulation leads to enhanced vascular remodeling in the skinfold window chamber and a proregenerative shift in macrophage and dendritic cell phenotype, resulting in improved wound closure after skin transplantation. As the targeting of functional immune subsets becomes the key to regenerative immunotherapies, single-cell pseudotime analysis tools will be vital in this field.

THU0140 COMORBIDITIES AMONG KOREAN WOMEN WITH RHEUMATOID ARTHRITIS IN CHILDBEARING YEARS: A NATIONWIDE POPULATION-BASED STUDY

Background:

Rheumatoid arthritis is a chronic systemic inflammatory disease known to be associated with many comorbidities. Many women with rheumatoid arthritis (RA) are diagnosed with the disease before completing childbearing, but the risk of comorbidities associated with RA among women in childbearing years is not known.

Objectives:

We aimed to investigate the risk of comorbidities among Korean women with RA in childbearing years.

Methods:

From National Health Insurance Service data of 2009-2016, containing inpatient and outpatient claim information for approximately 97% of the Korean population, we identified 20-44 year aged-women with RA and controls without rheumatic diseases such as RA, systemic lupus erythematosus, and ankylosing spondylitis. Prevalence of comorbidities including cancer (Ca), hypertension (HTN), hyperlipidemia (HLD), and diabetes mellitus (DM) were analyzed. The rheumatic diseases and comorbidities were defined by International Classification of Disease (ICD)-10 codes for disease classifications. The comorbidities associated with RA were defined by the ICD-10 codes presented after the RA diagnosis.

Results:

Total 23,756 women with RA and 208,941 controls were identified. Women with RA had significantly higher prevalence of all comorbidities analyzed compared with the controls (49.92% vs 25.58%, p<0.001). In women with RA, Ca (OR 1.14), DM (OR 1.22), HTN (OR 1.56), and HLD (OR 2.44) occurred significantly more often compared with the controls (p<0.001).

Conclusion:

During childbearing years, women with RA are more susceptible to comorbidities leading to a significant burden in this specific population of Korean women in childbearing years.

References:

[1]Dougados M: Comorbidities in rheumatoid arthritis. Current opinion in rheumatology 2016, 28(3):282-288.

[2]Choi IA, Park SH, Cha HS, Park W, Kim HA, Yoo DH, Baek HJ, Lee SG, Lee YJ, Park YB et al: Prevalence of co-morbidities and evaluation of their monitoring in Korean patients with rheumatoid arthritis: comparison with the results of an international, cross-sectional study (COMORA). International journal of rheumatic diseases 2018, 21(7):1414-1422.

Table 1.

Risk of comorbidities associated with RA among Korean women in childbearing years during 2009-2016

RA(n=23,756)Controls(n=208,941)p-valueOR95% CIn(%)n(%)Any comorbidities10,859(45.71)53,423(25.57)<.00012.302.234-2.367 Ca1,235(5.20)8,845(4.23)<.00011.141.072-1.217 DM1,885(7.93)12,606(6.03)<.00011.221.155-1.285 HTN3,274(13.78)17,052(8.16)<.00011.561.495-1.628 HLD8,046(33.87)34,672(16.60)<.00012.442.367-2.516

RA, rheumatoid arthritis; Ca, cancer; DM, diabetes mellitus; HTN, hypertension; HLD, hyperlipidemia; OR, odds ratio; CI, confidence interval

Disclosure of Interests:

None declared

FRI0526 THE INCIDENCE, PREVALENCE AND MEDICATION USE OF RHEUMATOID ARTHRITIS AMONG KOREAN WOMEN IN CHILDBEARING YEARS: A NATIONWIDE POPULATION-BASED STUDY

Background:

Rheumatoid arthritis (RA) predominantly affects women and has a significant impact on childbearing. Several population-based studies identifying incidence, prevalence, and medication use of RA have been reported, yet epidemiological studies focusing on women with RA in childbearing years are missing.

Objectives:

We aimed to identify the incidence, prevalence and medication use of RA among Korean women in childbearing years.

Methods:

From National Health Insurance Service (NHIS) data (2009-2016), containing inpatient and outpatient claim information for approximately 97% of the Korean population, we identified 9,217,139 women aged between 20-44 years. Incidence and prevalence of RA in the specific sociodemographic group of women in childbearing age were analyzed, and the prevalence of medication prescription were compared between women with RA and controls without rheumatic diseases such as RA, systemic lupus erythematosus, and ankylosing spondylitis. Individuals with RA were defined by the presence of International Classification of Disease, 10th revision code, M05. The medication use was defined as receiving > 90days prescriptions of NSAIDs, corticosteroids (CSs), and conventional synthetic (cs) disease modifying antirheumatic drugs (DMARDs) or > 1day prescription of biologic (b) DMARDs.

Results:

Total 24,590 women with RA were identified. The average incidence of RA during 2011-2016 among women in childbearing years was 24.1/100,000 person-years (PYs) (95% CI 20.91-27.31) with a yearly increase from 20.99/100,000 PYs in 2011 to 28.38/100,000 PYs in 2016. The average prevalence of RA during 2009-2016 among women in childbearing years was 105.2/100,000 PYs (95% CI 99.0-111.5) with a minimum of 95.7/100,000 PYs in 2009 and a maximum of 110.5/100,000 PYs in 2016. There were increasing trends in both incidence and prevalence of RA according to age among women in childbearing years peaking in the age group of 40-44 years. The prescriptions of NSAIDs, CSs, csDMARDs and bDMARDs were more frequent in women with RA than controls (NSAIDs; 94.21% vs 21.79%, CSs; 83.65% vs 4.28%, csDMARDs; 91.23% vs 0.41%, bDMARDs; 0.11% vs 0%, p<0.001).

Conclusion:

The incidence and prevalence of RA are high among Korean women in childbearing years, and medication use was significantly more frequent in this specific population than controls. High disease burden is imposed upon women in childbearing years.

References:

[1] Won S, Cho SK, Kim D, Han M, Lee J, Jang EJ, Sung YK, Bae SC: Update on the prevalence and incidence of rheumatoid arthritis in Korea and an analysis of medical care and drug utilization. Rheumatol Int 2018, 38(4):649-656.

[2] Smeele HTW, Dolhain R: Current perspectives on fertility, pregnancy and childbirth in patients with Rheumatoid Arthritis. Seminars in arthritis and rheumatism 2019, 49(3s):S32-s35.

Table 1.

Medication use among women with RA and controls in childbearing age between 20-44 years during 2009-2016

Control(n=155,486)RA(n=23,756)n(%)n(%)PNSAIDs33,887(21.79)22,380(94.21)<.0001Steroids6,653(4.28)19,871(83.65)<.0001csDMARDs634(0.41)21,673(91.23)<.0001bDMARDs0(0.00)27(0.11)<.0001

RA, rheumatoid arthritis; NSAID, non-steroidal anti-inflammatory drug; cs, conventional synthetic; b, biologic; DMARDs, disease modifying antirheumatic drugs

Disclosure of Interests:

None declared

Adapting re-usable elastomeric respirators to utilise anaesthesia circuit filters using a 3D-printed adaptor - a potential alternative to address N95 shortages during the COVID-19 pandemic

The COVID‐19 pandemic has increased the demand for disposable N95 respirators. Re‐usable elastomeric respirators may provide a suitable alternative. Proprietary elastomeric respirator filters may become depleted as demand increases. An alternative may be the virus/bacterial filters used in anaesthesia circuits, if they can be adequately fitted onto the elastomeric respirators. In addition, many re‐usable elastomeric respirators do not filter exhaled breaths. If used for sterile procedures, this would also require modification. We designed a 3D‐printed adaptor that permits elastomeric respirators to interface with anaesthesia circuit filters and created a simple modification to divert exhaled breaths through the filter. We conducted a feasibility study evaluating the performance of our modified elastomeric respirators. A convenience sample of eight volunteers was recruited. Quantitative fit testing, respiratory rate and end‐tidal carbon dioxide were recorded during fit testing exercises and after 1 h of wear. All eight volunteers obtained excellent quantitative fit testing throughout the trial. The mean (SD) end‐tidal carbon dioxide was 4.5 (0.5) kPa and 4.6 (0.4) kPa at baseline and after 1 h of wear (p = 0.148). The mean (SD) respiratory rate was 17 (4) breaths.min⁻¹ and 17 (3) breaths.min⁻¹ at baseline and after 1 h of wear (p = 0.435). Four out of eight subjects self‐reported discomfort; two reported facial pressure, one reported exhalation resistance and one reported transient dizziness on exertion. Re‐usable elastomeric respirators to utilise anaesthesia circuit filters through a 3D‐printed adaptor may be a potential alternative to disposable N95 respirators during the COVID‐19 pandemic.

P574Accuracy of wrist-worn heart rate monitors for chronotropic assessment in atrial fibrillation

Introduction

Wrist-worn fitness and heart rate (HR) monitors are increasingly popular. Previous studies in healthy participants with sinus rhythm (SR) have yielded variable results depending on HR, activity levels and device tested. A paucity of data exists on their accuracy in atrial fibrillation (AF) in ambulatory patients.

Purpose

We sought to assess the HR accuracy of 2 commercially available smart watches (Fitbit Charge HR [FB] and Apple Watch Series 3 [AW]) compared with Holter monitoring in an ambulant patient cohort.

Methods

Patients aged >18 years referred for 24-hour Holter monitoring were prospectively recruited. The Holter monitor was the criterion measure. Each patient was randomly allocated to either a FB or AW along with their Holter monitor. The study protocol was approved by the institutional review board.

Statistical analysis: Pearson (r) correlation coefficients and Bland-Altman comparison with 95% limits of agreement (LoA) were evaluated to assess criterion validity and agreement between the smart watch and Holter ECG-HR. Bias was the calculated mean difference between the smart watch and ECG-HR. A ± 10-beat different between Holter-HR and SW-HR was used as a clinically relevant range to establish the accuracy of HR estimation by SW.

Results

Across all devices, 53,288 hear rate values were recorded from 32 patients. Twenty six patients were in persistent AF and six were in SR. Twelve patients wore the FB while 20 wore the AW. In the FB arm, nice patient were in persistent AF and three in SR. In the AW arm, persistent AF was the rhythm in seventeen and SR in three. Patients in SR demonstrated overall strong agreement compared to Holter monitoring (Mean Bias <1 beat, LoA −11 to 11 beats) and a correlation coefficient of 0.87 (p<0.001). In AF, both devices underestimated HR measurements (Overall Bias −9 beats, LoA −41 to 23, r=0.60, p<0.001). The AW had lower bias and narrower LoA compared to FB (−5 beats vs −13 beats, LoA −31 to 21 beats vs −50 to 22 beats). Using a ± 10-beat range against ECG-HR for clinical accuracy, both the AW and FB performed satisfactorily in SR with 95.2% of AW and 92.2% of FB HR readings considered valid. In AF, however, the AW-HR readings were within the ± 10-beat threshold in 76.5% of the time compared with only 56.1% of FB readings.

Conclusion

In ambulatory patients, smart watches were accurate in HR estimation when compared to Holter monitor in SR; however tended to underestimate HR in AF. Further improvements in device technology are needed before the widespread consumer adoption of this nascent technology for chronotropic assessment in arrhythmias.

The interaction of Lolium latent virus major coat protein with ankyrin repeat protein NbANKr redirects it to chloroplasts and modulates virus infection

The Lolium latent virus (LoLV) major coat protein sequence contains a typical chloroplast transit peptide (cTP) domain. In infected Nicotiana benthamiana leaf tissue, LoLV coat proteins can be detected at the chloroplast. In transient expression, several N-terminal deletions of the CP sequence, increasing in length, result in disruption of the domain functionality, markedly affecting intracellular localization. A yeast two-hybrid-based study using LoLV CP as bait identified several potentially interacting Arabidopsis host proteins, most of them with chloroplast-linked pathways. One of them, an ankyrin repeat protein, was studied in detail. The N. benthamiana homologue (NbANKr) targets chloroplasts, is able to co-localize with LoLV CP at chloroplast membranes in transient expression and shows a robust interaction with LoLV CP in vivo by BiFC, which has been confirmed by yeast two-hybrid data. Silencing NbANKr genes in N. benthamiana plants, prior to challenging with LoLV by mechanical inoculation, affects LoLV infection, significantly reducing the level of viral RNA in young leaves, compared to levels in control plants, and suggesting an inhibition of virus movement. Silencing of NbANKr has no obvious effect on plant phenotype, but is able to interfere with LoLV infection, opening the way for a new strategy for virus infection control.

A Study on CYP2C19 and CYP2D6 Polymorphic Effects on Pharmacokinetics and Pharmacodynamics of Amitriptyline in Healthy Koreans

We performed a double-blinded, genotype-based stratification study to explore the pharmacokinetics and pharmacodynamics of amitriptyline according to CYP2C19 and CYP2D6 genotype in Korean subjects. Twenty-four healthy adults were grouped by genotype of CYP2C19 and CYP2D6. After a single dose of 25 mg of amitriptyline, blood samples were collected and anticholinergic effects were measured. The extent of N-demethylation of amitriptyline significantly decreased in subjects carrying two nonfunctional alleles of CYP2C19. The extent of hydroxylation of amitriptyline or nortriptyline was significantly reduced in subjects carrying two CYP2D6 decreased functional alleles compared with those with no or one decreased functional allele. The overall metabolic pathway of amitriptyline was more likely to be dominated by CYP2C19 than CYP2D6. The gene variations of CYP2C19 and CYP2D6 did not change the pharmacodynamic effect. The findings of this study will provide useful information on individualized drug treatment with amitriptyline considering both CYP2D6 and CYP2C19 gene variations.

Population Pharmacokinetic and Pharmacodynamic Modeling Analysis of GCC-4401C, a Novel Direct Factor Xa Inhibitor, in Healthy Volunteers

GCC‐4401C, an orally active direct factor Xa inhibitor that is similar to rivaroxaban, is currently under development for venous thromboembolic disease (VTE). The purpose of this study was to characterize the pharmacokinetics (PKs) and pharmacodynamics (PDs) of GCC‐4401C by population modeling analysis and to predict proper dosage regimens compared to rivaroxaban using data from two phase I clinical studies. Plasma GCC‐4401C concentrations over time were best described by a two‐compartment linear model and body weight was associated with central volume of distribution. Relevant PD markers generally changed in a dose‐dependent manner and were described well with sigmoid, simple maximum effect, or linear models. GCC‐4401C was absorbed more rapidly than rivaroxaban. Comparisons based on simulations of PD marker changes over time suggest that 20 mg and 40 mg of GCC‐4401C administered under fasted status are comparable to 10 mg and 20 mg of rivaroxaban under fed status.

The fear-avoidance model of chronic pain: assessing the role of neuroticism and negative affect in pain catastrophizing using structural equation modeling

BACKGROUND

Previous research on the fear-avoidance model (FAM) of chronic pain suggests that the personality traits of neuroticism and negative affect (NA) influence pain catastrophizing. However, the mechanisms of their influence on pain catastrophizing remain unclear.

PURPOSE

This study examined four possible models of relationships between neuroticism, NA, and pain catastrophizing within the FAM framework using structural equation modeling.

METHOD

A total of 401 patients with chronic musculoskeletal pain completed measures of neuroticism, NA, three core FAM components (pain catastrophizing, pain-related fear, and pain anxiety), and adjustment outcomes (pain-related disability and depression).

RESULTS

Regression analyses refuted the possibility that neuroticism and NA moderated each other's effect on pain catastrophic thoughts (p > 0.05). Results of structural equation modeling (SEM) evidenced superior data-model fit for the collapsed models in which neuroticism and NA were two secondary traits underlying a latent construct, negative emotion (disability: comparative fit index (CFI) = 0.93; depression: CFI = 0.91).

CONCLUSION

The results offer preliminary evidence that patients presenting with more neurotic symptom and heightened NA probably elicit more catastrophic thoughts about pain.

Enhancement of spin-wave nonreciprocity in magnonic crystals via synthetic antiferromagnetic coupling

Spin-wave nonreciprocity arising from dipole-dipole interaction is insignificant for magnon wavelengths in the sub-100 nm range. Our micromagnetic simulations reveal that for the nanoscale magnonic crystals studied, such nonreciprocity can be greatly enhanced via synthetic antiferromagnetic coupling. The nonreciprocity is manifested as highly asymmetric magnon dispersion curves of the magnonic crystals. Furthermore, based on the study of the dependence of the nonreciprocity on an applied magnetic field, the antiparallel alignment of the magnetizations is shown to be responsible for the enhancement. Our findings would be useful for magnonic and spintronics applications.

Comparison of filter media materials for heavy metal removal from urban stormwater runoff using biofiltration systems

The filter media in biofiltration systems play an important role in removing potentially harmful pollutants from urban stormwater runoff. This study compares the heavy metal removal potential (Cu, Zn, Cd, Pb) of five materials (potting soil, compost, coconut coir, sludge and a commercial mix) using laboratory columns. Total/dissolved organic carbon (TOC/DOC) was also analysed because some of the test materials had high carbon content which affects heavy metal uptake/release. Potting soil and the commercial mix offered the best metal uptake when dosed with low (Cu: 44.78 μg/L, Zn: 436.4 μg/L, Cd, 1.82 μg/L, Pb: 51.32 μg/L) and high concentrations of heavy metals (Cu: 241 μg/L, Zn: 1127 μg/L, Cd: 4.57 μg/L, Pb: 90.25 μg/L). Compost and sludge also had high removal efficiencies (>90%). Heavy metal leaching from these materials was negligible. A one-month dry period between dosing experiments did not affect metal removal efficiencies. TOC concentrations from all materials increased after the dry period. Heavy metal removal was not affected by filter media depth (600 mm vs. 300 mm). Heavy metals tended to accumulate at the upper 5 cm of the filter media although potting soil showed bottom-enriched concentrations. We recommend using potting soil as the principal media mixed with compost or sludge since these materials perform well and are readily available. The use of renewable materials commonly found in Singapore supports a sustainable approach to urban water management.

Multiple regression analysis in modeling of columnar ozone in Peninsular Malaysia

This study aimed to predict monthly columnar ozone (O3) in Peninsular Malaysia by using data on the concentration of environmental pollutants. Data (2003-2008) on five atmospheric pollutant gases (CO2, O3, CH4, NO2, and H2O vapor) retrieved from the satellite Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) were employed to develop a model that predicts columnar ozone through multiple linear regression. In the entire period, the pollutants were highly correlated (R = 0.811 for the southwest monsoon, R = 0.803 for the northeast monsoon) with predicted columnar ozone. The results of the validation of columnar ozone with column ozone from SCIAMACHY showed a high correlation coefficient (R = 0.752-0.802), indicating the model's accuracy and efficiency. Statistical analysis was utilized to determine the effects of each atmospheric pollutant on columnar ozone. A model that can retrieve columnar ozone in Peninsular Malaysia was developed to provide air quality information. These results are encouraging and accurate and can be used in early warning of the population to comply with air quality standards.

Community-based wastewater treatment systems and water quality of an Indonesian village

This paper examines the impact of community-based water treatment systems on water quality in a peri-urban village in Yogyakarta, Indonesia. Water samples were taken from the wastewater treatment plants (WWTPs), irrigation canals, paddy fields and wells during the dry and wet seasons. The samples were tested for biological and chemical oxygen demand, nutrients (ammonia, nitrate, total nitrogen and total phosphorus) and Escherichia coli. Water quality in this village is affected by the presence of active septic tanks, WWTP effluent discharge, small-scale tempe industries and external sources. We found that the WWTPs remove oxygen-demanding wastes effectively but discharged nutrients, such as nitrate and ammonia, into irrigation canals. Irrigation canals had high levels of E. coli as well as oxygen-demanding wastes. Well samples had high E. coli, nitrate and total nitrogen levels. Rainfall tended to increase concentrations of biological and chemical oxygen demand and some nutrients. All our samples fell within the drinking water standards for nitrate but failed the international and Indonesian standards for E. coli. Water quality in this village can be improved by improving the WWTP treatment of nutrients, encouraging more villagers to be connected to WWTPs and controlling hotspot contamination areas in the village.