The rocky road to freedom: number of countries transited during defection and risk of metabolic syndrome among North Korean Refugees in South Korea

OBJECTIVES

North Korean Refugees (NKRs) undergo defection, and this has been shown to impact their current health status in South Korea. However, little is understood about how the defection process is related to metabolic syndrome (MetS). This study regarded the defection process to be a quasi-measurement of traumatic experience and investigated whether defection was a risk factor for MetS among NKRs living in South Korea.

STUDY DESIGN

This cross-sectional study obtained data from the Korea University Anam Hospital in Seoul. NKRs (N = 847) voluntarily completed questionnaires and underwent at least one medical examination between October 2008 and July 2021.

METHODS

Multivariable logistic regression models were used to evaluate whether the number of countries transited by NKRs was associated with MetS by controlling for covariates.

RESULTS

The prevalence of MetS among male and female NKRs in South Korea was 12.3% and 13.3%, respectively. The highest prevalence of MetS (33.4%) was among NKRs who had transited two countries. The number of months in transit countries (mean: 49.9 ± 51.7) and period of residence in South Korea (mean: 40.9 ± 40.9 months) were also considered. NKRs who transited three countries had a higher probability of MetS (odds ratio [OR] 2.660, 95% confidence interval [CI] 1.161-6.097) than those who travelled directly to South Korea. NKRs who transited three countries and had only resided in South Korea for a short period had a higher probability of MetS (OR 3.424, 95% CI 1.149-10.208) than those who have lived in South Korea for a longer period.

CONCLUSIONS

Considering the social vulnerability of NKRs and consequential health problems, there is an urgent need for appropriate support from the government and society.

Molecular signature of neutrophil extracellular trap mediating disease module in idiopathic inflammatory myopathy

The rarity and heterogeneity of idiopathic inflammatory myopathy (IIM) pose challenges for researching IIM in affected individuals. We analyzed integrated transcriptomic datasets obtained using muscle tissues from patients with five distinct IIM subtypes to investigate the shared and distinctive cellular and molecular characteristics. A transcriptomic dataset of muscle tissues from normal controls (n = 105) and patients with dermatomyositis (n = 89), polymyositis (n = 33), inclusion body myositis (n = 121), immune-mediated necrotizing myositis (n = 75), and anti-synthetase syndrome (n = 18) was used for differential gene-expression analysis, functional-enrichment analysis, gene set-enrichment analysis, disease-module identification, and kernel-based diffusion scoring. Damage-associated molecular pattern-associated pathways and neutrophil-mediated immunity were significantly enriched across different IIM subtypes, although their activities varied. Interferons-signaling pathways were differentially activated across all five IIM subtypes. In particular, neutrophil extracellular trap (NET) formation was significantly activated and correlated with Fcγ R-mediated signaling pathways. NET formation-associated genes were key for establishing disease modules, and FCGRs, C1QA, and SERPINE1 markedly perturbed the disease modules. Integrated transcriptomic analysis of muscle tissues identified NETs as key components of neutrophil-mediated immunity involved in the pathogenesis of IIM subtypes and, thus, has therapeutically targetable value.

Quantitative prediction of radiographic progression in patients with axial spondyloarthritis using neural network model in a real-world setting

BACKGROUND

Predicting radiographic progression in axial spondyloarthritis (axSpA) remains limited because of the complex interaction between multiple associated factors and individual variability in real-world settings. Hence, we tested the feasibility of artificial neural network (ANN) models to predict radiographic progression in axSpA.

METHODS

In total, 555 patients with axSpA were split into training and testing datasets at a 3:1 ratio. A generalized linear model (GLM) and ANN models were fitted based on the baseline clinical characteristics and treatment-dependent variables for the modified Stoke Ankylosing Spondylitis Spine Score (mSASSS) of the radiographs at follow-up time points. The mSASSS prediction was evaluated, and explainable machine learning methods were used to provide insights into the model outcome or prediction.

RESULTS

The R² values of the fitted models were in the range of 0.90-0.95 and ANN with an input of mSASSS as the number of each score performed better (root mean squared error (RMSE) = 2.83) than GLM or input of mSASSS as a total score (RMSE = 2.99-3.57). The ANN also effectively captured complex interactions among variables and their contributions to the transition of mSASSS over time in the fitted models. Structural changes constituting the mSASSS scoring systems were the most important contributing factors, and no detectable structural abnormalities at baseline were the most significant factors suppressing mSASSS change.

CONCLUSIONS

Clinical and radiographic data-driven ANN allows precise mSASSS prediction in real-world settings. Correct evaluation and prediction of spinal structural changes could be beneficial for monitoring patients with axSpA and developing a treatment plan.

Exploratory use of romosozumab for osteoporosis in a patient with Hajdu-Cheney syndrome: a case report

Hajdu-Cheney syndrome (HCS) is an inherited skeletal disorder caused by mutations in the Notch homolog protein 2 gene (NOTCH2). Treatment of this rare disease is challenging because there are no established guidelines worldwide. Previous case reports using bisphosphonates, denosumab, or teriparatide suggested that curative treatment for HCS did not exist yet in terms of preventing the disease progression. Therefore, the efficacy of romosozumab for osteoporosis in patients with HCS needs to be evaluated. Herein, we report the case of a 43-year-old woman who had progressive acro-osteolysis and repeated fractures since the age of 29 years. Next-generation sequencing confirmed HCS with a mutation at nucleotide 6758G>A, leading to Trp2253Ter replacement in NOTCH2. Romosozumab treatment was initiated because she had already received bisphosphonate for more than 10 years at other hospitals. After 1 year of romosozumab treatment, the bone mineral density (BMD) increased by 10.2%, 6.3%, and 1.3%, with Z scores of -2.9, -1.6, and -1.2 at the lumbar spine, femoral neck, and total hip, respectively. In addition, C-telopeptide was suppressed by 26.4% (0.121 to 0.089 ng/mL), and procollagen type I N-terminal propeptide increased by 18.7% (25.2 to 29.9 ng/mL). This was the first report of romosozumab treatment in patient with osteoporosis and HCS in Korea. One year of romosozumab treatment provided substantial gains in BMD with maintaining the last acro-osteolytic status without deteriorating, representing a possible treatment option for HCS.

Clinical Implications of Shared Epitope and Anti-citrullinated Peptide Antibody in Patients With Rheumatoid Arthritis

Objective

The shared epitope (SE) and anti-citrullinated peptide antibody (ACPA) are involved in the pathogenesis of rheumatoid arthritis (RA). This study evaluated the clinical implications of SE and ACPA in terms of disease manifestation and response to biologic disease modifying anti-rheumatic drugs (DMARDs).

Methods

Patients with identified human leukocyte antigen (HLA)-DRB1 alleles were included to compare the clinical characteristics and drug survival rate of tumor necrosis factor (TNF) inhibitors or abatacept based on the presence of SE and ACPA.

Results

Of the 533 patients with identified HLA-DRB1 alleles, 329 patients (61.7%) with SE alleles showed higher disease activity and erosive changes compared to patients without SE alleles. SE-positive patients were more likely to start biologic (b-) or targeted synthetic DMARDs (tsDMARDs) within the first 5 years (p=0.020). The presence of SE, smoking, dyslipidemia, and higher erythrocyte sedimentation rate were independently associated with the initiation of b- or tsDMARDs (p=0.016, 0.028, 0.031, and 0.001, respectively). The presence of SE and ACPA did not affect the drug survival rate of TNF inhibitors, whereas the abatacept retention rate was higher in ACPA-positive patients (p=0.024).

Conclusion

The presence of SE affected disease characteristics and prognosis in Korean patients with RA without a significant impact on drug survival rate of TNF inhibitors and abatacept. ACPA positivity was associated with abatacept drug retention, suggesting that abatacept may be helpful in ACPA-positive patients than in ACPA-negative patients.

Use of Disease-modifying Antirheumatic Drugs After Cancer Diagnosis in Rheumatoid Arthritis Patients

Objective

There is no recommendation for the use of disease-modifying antirheumatic drugs (DMARDs) in patients with rheumatoid arthritis (RA) who developed cancer. We examined changes in the DMARDs prescription patterns associated with cancer diagnosis in RA patients.

Methods

We reviewed the medical records of 2,161 RA patients who visited rheumatology clinic between January 2008 and February 2017 and found 40 patients who developed cancer during RA treatment. In these patients, we examined DMARDs prescription patterns before and right after cancer diagnosis and at recent outpatient clinic visits.

Results

Before cancer diagnosis, methotrexate (MTX)-combined conventional synthetic DMARDs (csDMARDs) were most commonly prescribed (22, 55.0%) and biological DMARDs (biologics) in nine patients (22.5%). For cancer treatment, 19 patients received chemotherapy (including adjuvant chemotherapy) and 21 patients had surgery only. Right after cancer diagnosis, changes in the DMARDs prescription patterns were similar in discontinuation (13, 32.5%), switching (14, 35.0%), and maintenance (13, 32.5%). DMARDs were discontinued more frequently in the chemotherapy group (9/19, 47.4%) than the surgery only group (4/2, 19.0%) (p<0.05). Among the 13 patients who discontinued DMARDs, nine (69.2%) resumed DMARDs after a median of 5.5 months (interquartile range [IQR] 2.9, 18.3) due to arthritis flare. At a median of 4.6 years (IQR 3.3, 6.7) after cancer diagnosis, 25 patients were evaluated at recent outpatient clinic visits. Four patients received no DMARD, three MTX monotherapies, 11 csDMARDs combination therapies, and seven biologics.

Conclusion

A significant number of RA patients who developed cancer during RA treatment were still receiving DMARDs including biologics after cancer diagnosis.

Integrative analysis of lung molecular signatures reveals key drivers of idiopathic pulmonary fibrosis

Background

Idiopathic pulmonary fibrosis (IPF) is a devastating disease with a high clinical burden. The molecular signatures of IPF were analyzed to distinguish molecular subgroups and identify key driver genes and therapeutic targets.

Methods

Thirteen datasets of lung tissue transcriptomics including 585 IPF patients and 362 normal controls were obtained from the databases and subjected to filtration of differentially expressed genes (DEGs). A functional enrichment analysis, agglomerative hierarchical clustering, network-based key driver analysis, and diffusion scoring were performed, and the association of enriched pathways and clinical parameters was evaluated.

Results

A total of 2,967 upregulated DEGs was filtered during the comparison of gene expression profiles of lung tissues between IPF patients and healthy controls. The core molecular network of IPF featured p53 signaling pathway and cellular senescence. IPF patients were classified into two molecular subgroups (C1, C2) via unsupervised clustering. C1 was more enriched in the p53 signaling pathway and ciliated cells and presented a worse prognostic score, while C2 was more enriched for cellular senescence, profibrosing pathways, and alveolar epithelial cells. The p53 signaling pathway was closely correlated with a decline in forced vital capacity and carbon monoxide diffusion capacity and with the activation of cellular senescence. CDK1/2, CKDNA1A, CSNK1A1, HDAC1/2, FN1, VCAM1, and ITGA4 were the key regulators as evidence by high diffusion scores in the disease module. Currently available and investigational drugs showed differential diffusion scores in terms of their target molecules.

Conclusions

An integrative molecular analysis of IPF lungs identified two molecular subgroups with distinct pathobiological characteristics and clinical prognostic scores. Inhibition against CDKs or HDACs showed great promise for controlling lung fibrosis. This approach provided molecular insights to support the prediction of clinical outcomes and the selection of therapeutic targets in IPF patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01749-3.

Association of influenza infection with hospitalisation-related systemic lupus erythematosus flares: a time series analysis

OBJECTIVES

This study aimed to investigate whether the influenza annual outbreak in Korea is related to hospitalisation-related flares in systemic lupus erythematosus (SLE) patients.

METHODS

The weekly frequency of hospitalisation-related SLE flares (2012-2015) was collected from the Korean National Health Insurance claim database. The weekly laboratory-confirmed detection rate of influenza infection was obtained from the Korea Centers for Disease Control and Prevention database. A generalised linear model was used to examine the relative risks (RRs) of hospitalisation-related SLE flares associated with influenza infection, after adjusting for time trends and meteorological data.

RESULTS

A total of 2,223 hospitalisation-related SLE flares were analysed. An interquartile range (24.5%) increase in influenza infection was associated with a 14.0% increase in hospitalisation-related SLE flares (RR, 1.14; 95% confidence interval [CI]: 1.04-1.25; p=0.006). In addition, influenza infections at lag 0-1 (over 2 weeks including concurrent and 1 previous week) and lag 0-2 (over 3 weeks including concurrent and 2 previous weeks) were associated with increase in hospitalisation-related SLE flares (RR, 1.14; 95% confidence interval [CI]: 1.03-1.26; p=0.014 and RR, 1.13; 95% CI: 1.02-1.26; p=0.023). Significant associations were especially observed in women (RR, 1.15; 95% CI: 1.15-1.16; p=0.006) and immunosuppressant (RR, 1.26; 95% CI: 1.26-1.27; p<0.001) or glucocorticoid recipients (RR, 1.17, 95% CI: 1.16-1.17; p=0.004).

CONCLUSIONS

This study shows a significant association between seasonal influenza infection and flares in SLE patients, which suggests influenza can be a novel environmental risk factor for SLE flares.

Transverse bunch-by-bunch feedback system for time-resolved experiments at PLS-II

A description of the upgraded bunch-by-bunch feedback system for time-resolved experiments at Pohang Light Source II (PLS-II) is provided. The bunch-by-bunch feedback system has been upgraded to increase the single-bunch current in the hybrid fill pattern of the PLS-II facility. The project is part of the SPring-8 and PLS-II collaboration. The main features of the upgrade are to employ a single 500 MHz analog-to-digital converter (ADC) instead of the previous four 125 MHz interleaved ADCs for 500 MHz rate, to replace a single-loop two-dimensional feedback with two independent one-dimensional feedback loops, to implement the tune measurement function with a single bunch, and mainly to implement single-bunch and stretcher control. The realization of a 400 mA hybrid fill pattern including a 10 mA single bunch demonstrates the precision of the upgraded bunch-by-bunch feedback system.

Deep phenotyping of synovial molecular signatures by integrative systems analysis in rheumatoid arthritis

OBJECTIVE

RA encompasses a complex, heterogeneous and dynamic group of diseases arising from molecular and cellular perturbations of synovial tissues. The aim of this study was to decipher this complexity using an integrative systems approach and provide novel insights for designing stratified treatments.

METHODS

An RNA sequencing dataset of synovial tissues from 152 RA patients and 28 normal controls was imported and subjected to filtration of differentially expressed genes, functional enrichment and network analysis, non-negative matrix factorization, and key driver analysis. A naïve Bayes classifier was applied to the independent datasets to investigate the factors associated with treatment outcome.

RESULTS

A matrix of 1241 upregulated differentially expressed genes from RA samples was classified into three subtypes (C1-C3) with distinct molecular and cellular signatures. C3 with prominent immune cells and proinflammatory signatures had a stronger association with the presence of ACPA and showed a better therapeutic response than C1 and C2, which were enriched with neutrophil and fibroblast signatures, respectively. C2 was more occupied by synovial fibroblasts of destructive phenotype and carried highly expressed key effector molecules of invasion and osteoclastogenesis. CXCR2, JAK3, FYN and LYN were identified as key driver genes in C1 and C3. HDAC, JUN, NFKB1, TNF and TP53 were key regulators modulating fibroblast aggressiveness in C2.

CONCLUSIONS

Deep phenotyping of synovial heterogeneity captured comprehensive and discrete pathophysiological attributes of RA regarding clinical features and treatment response. This result could serve as a template for future studies to design stratified approaches for RA patients.

Integrative analysis of lung molecular signatures reveals key drivers of systemic sclerosis-associated interstitial lung disease

OBJECTIVES

Interstitial lung disease is a significant comorbidity and the leading cause of mortality in patients with systemic sclerosis. Transcriptomic data of systemic sclerosis-associated interstitial lung disease (SSc-ILD) were analysed to evaluate the salient molecular and cellular signatures in comparison with those in related pulmonary diseases and to identify the key driver genes and target molecules in the disease module.

METHODS

A transcriptomic dataset of lung tissues from patients with SSc-ILD (n=52), idiopathic pulmonary fibrosis (IPF) (n=549), non-specific interstitial pneumonia (n=49) and pulmonary arterial hypertension (n=81) and from normal healthy controls (n=331) was subjected to filtration of differentially expressed genes, functional enrichment analysis, network-based key driver analysis and kernel-based diffusion scoring. The association of enriched pathways with clinical parameters was evaluated in patients with SSc-ILD.

RESULTS

SSc-ILD shared key pathogenic pathways with other fibrosing pulmonary diseases but was distinguishable in some pathological processes. SSc-ILD showed general similarity with IPF in molecular and cellular signatures but stronger signals for myofibroblasts, which in SSc-ILD were in a senescent and apoptosis-resistant state. The p53 signalling pathway was the most enriched signature in lung tissues and lung fibroblasts of SSc-ILD, and was significantly correlated with carbon monoxide diffusing capacity of lung, cellular senescence and apoptosis. EEF2, EFF2K, PHKG2, VCAM1, PRKACB, ITGA4, CDK1, CDK2, FN1 and HDAC1 were key regulators with high diffusion scores in the disease module.

CONCLUSIONS

Integrative transcriptomic analysis of lung tissues revealed key signatures of fibrosis in SSc-ILD. A network-based Bayesian approach provides deep insights into key regulatory genes and molecular targets applicable to treating SSc-ILD.

Switching from TNFα inhibitor to tacrolimus as maintenance therapy in rheumatoid arthritis after achieving low disease activity with TNFα inhibitors and methotrexate: 24-week result from a non-randomized, prospective, active-controlled trial

Background

Tapering or stopping biological disease-modifying anti-rheumatic drugs has been proposed for patients with rheumatoid arthritis (RA) in remission, but it frequently results in high rates of recurrence. This study evaluates the efficacy and safety of tacrolimus (TAC) as maintenance therapy in patients with established RA in remission after receiving combination therapy with tumor necrosis factor inhibitor (TNFi) and methotrexate (MTX).

Methods

This 24-week, prospective, open-label trial included patients who received TNFi and MTX at stable doses for ≥24 weeks and had low disease activity (LDA), measured by Disease Activity Score-28 for ≥12 weeks. Patients selected one of two arms: maintenance (TNFi plus MTX) or switched (TAC plus MTX). The primary outcome was the difference in the proportion of patients maintaining LDA at week 24, which was assessed using a logistic regression model. Adverse events were monitored throughout the study period.

Results

In efficacy analysis, 80 and 34 patients were included in the maintenance and switched arms, respectively. At week 24, LDA was maintained in 99% and 91% of patients in the maintenance and switched arms, respectively (odds ratio, 0.14; 95% confidence interval, 0.01–1.59). Drug-related adverse effects tended to be more common in the switched arm than in the maintenance arm (20.9% versus 7.1%, respectively) but were well-tolerated.

Conclusion

This controlled study tested a novel treatment strategy of switching from TNFi to TAC in RA patients with sustained LDA, and the findings suggested that TNFi can be replaced with TAC in most patients without the patients experiencing flare-ups for at least 24 weeks.

Trial registration

Korea CDC CRIS, KCT0005868. Registered 4 February 2021—retrospectively registered

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02566-z.

Author Correction: Network-based modeling of drug effects on disease module in systemic sclerosis

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Consensus on Components of Frailty Using the Delphi Method: Korean Frailty and Aging Cohort Study

BACKGROUND

The concept of frailty has been suggested to comprise physical, mental, and social phenotypes. However, there is no general consensus about the appropriate components for assessing frailty.

OBJECTIVES

The purpose of this study was to reach consensus on components of frailty assessment using the Delphi process.

METHODS

To achieve consensus on the definition of frailty, a modified Delphi method was used. Geriatric and gerontologic experts were selected from various fields. The detailed components of frailty were composed of data from the Korean Frailty and Aging Cohort Study. Establishing consensus and collecting opinions from experts were conducted using a modified Delphi method.

RESULTS

Overall, nine domains with 14 components of frailty assessment were accepted. There was consensus on the necessity of a broad phenotype including physical, mental, and social frailty.

CONCLUSIONS

Consensus on the components of a frailty assessment in a clinical setting is achieved through the Delphi process to establish a new tool of frailty assessment.

Long-term clinical outcomes of endoscopic submucosal dissection for colorectal neoplasia with or without the hybrid technique

AIM

The main aim of this study was to compare the long-term outcome of a conventional colorectal endoscopic submucosal dissection (ESD) in which submucosal dissection was continued throughout until the completion of resection (ESD-T) to hybrid endoscopic submucosal dissection (ESD-H) in the colorectum.

METHOD

Medical records of 836 colorectal neoplasia patients treated by ESD-T or ESD-H were reviewed. ESD-H was defined as colorectal ESD with additional snaring in the final stage of the procedure. Primary outcomes were the overall and metastatic recurrence rates. Secondary outcomes were short-term outcomes such as the en bloc resection rate, procedure time and adverse events.

RESULTS

The overall recurrence rate was higher in the ESD-H than in the ESD-T group (5.7% vs 0.7%, P = 0.001). The metastatic recurrence rate showed no significant difference between these groups (1.4% vs 1.4%, P = 1.000). Multivariate analysis revealed that a failed en bloc resection (hazard ratio 24.097; 95% CI 5.446-106.237; P < 0.001) and larger tumour size (hazard ratio 1.042; 95% CI 1.014-1.070; P = 0.003) were independently associated with overall recurrence. The ESD-H group showed a lower en bloc resection rate (56.8% vs 96.5%, P < 0.001), shorter procedure time (45.6 vs 54.3 min, P < 0.001) and higher perforation rate (10.3% vs 6.0%, P = 0.029).

CONCLUSION

Although long-term outcomes in terms of overall recurrence are inferior following ESD-H, a failed en bloc resection and large tumour size are the only independent risk factors for recurrence. Further investigations are warranted to improve the long-term outcomes of ESD-H.

Network-based modeling of drug effects on disease module in systemic sclerosis

The network-based proximity between drug targets and disease genes can provide novel insights regarding the repercussions, interplay, and repositioning of drugs in the context of disease. Current understanding and treatment for reversing of the fibrotic process is limited in systemic sclerosis (SSc). We have developed a network-based analysis for drug effects that takes into account the human interactome network, proximity measures between drug targets and disease-associated genes, genome-wide gene expression and disease modules that emerge through pertinent analysis. Currently used and potential drugs showed a wide variation in proximity to SSc-associated genes and distinctive proximity to the SSc-relevant pathways, depending on their class and targets. Tyrosine kinase inhibitors (TyKIs) approach disease gene through multiple pathways, including both inflammatory and fibrosing processes. The SSc disease module includes the emerging molecular targets and is in better accord with the current knowledge of the pathophysiology of the disease. In the disease-module network, the greatest perturbing activity was shown by nintedanib, followed by imatinib, dasatinib, and acetylcysteine. Suppression of the SSc-relevant pathways and alleviation of the skin fibrosis was remarkable in the inflammatory subsets of the SSc patients receiving TyKI therapy. Our results show that network-based drug-disease proximity offers a novel perspective into a drug’s therapeutic effect in the SSc disease module. This could be applied to drug combinations or drug repositioning, and be helpful guiding clinical trial design and subgroup analysis.

Risk factors for cervical spine instability in patients with rheumatoid arthritis

INTRODUCTION

Cervical spine (C-spine) instability is a unique and significant characteristic of rheumatoid arthritis (RA) because its occurrence is not rare and it can cause compressive cervical myelopathy, which may lead to serious neurologic sequelae. This study evaluated the prevalence and risk factors of C-spine instabilities in RA patients with a focus on anti-citrullinated protein antibody (ACPA) and biologic disease-modifying antirheumatic drug (DMARD) therapies.

METHODS

The presence of C-spine instabilities in 1114 patients with RA was evaluated using C-spine radiographies according to the defined metrics. Multivariable logistic regression analyses were performed to identify independent predictors of C-spine instability. The initiation of biologic DMARDs was assessed via a Kaplan-Meier analysis and compared using log-rank tests.

RESULTS

In total, 306 (27.5%) patients presented with C-spine instabilities. The most common type was atlantoaxial subluxation (AAS; n = 199 [17.9%]). Male sex, positivity for rheumatoid factor and ACPA, erosive change in the peripheral joints, and presence of osteoporosis were independently associated with C-spine instabilities (all P < 0.05). In particular, positivity for ACPA was the most powerful risk factor (odds ratio: 2.33 [95% confidence interval: 1.37, 3.96], P = 0.002), and it was closely associated with AAS. Patients with AAS were at a higher risk for early initiation of biologic DMARDs.

CONCLUSIONS

Positivity for ACPA was a significant risk factor for C-spine instability, and AAS was remarkably correlated to the early initiation of biologic DMARDs, a surrogate index of poor long-term outcomes. Key Points • The presence of antibodies against citrullinated proteins was a strong risk factor for C-spine instability in patients with rheumatoid arthritis. • Atlantoaxial subluxation was significantly associated with early initiation of biologic DMARDs, a surrogate index of poor long-term outcome.

Integrated systems analysis of salivary gland transcriptomics reveals key molecular networks in Sjögren's syndrome

Background

Treatment of patients with Sjögren’s syndrome (SjS) is a clinical challenge with high unmet needs. Gene expression profiling and integrative network-based approaches to complex disease can offer an insight on molecular characteristics in the context of clinical setting.

Methods

An integrated dataset was created from salivary gland samples of 30 SjS patients. Pathway-driven enrichment profiles made by gene set enrichment analysis were categorized using hierarchical clustering. Differentially expressed genes (DEGs) were subjected to functional network analysis, where the elements of the core subnetwork were used for key driver analysis.

Results

We identified 310 upregulated DEGs, including nine known genetic risk factors and two potential biomarkers. The core subnetwork was enriched with the processes associated with B cell hyperactivity. Pathway-based subgrouping revealed two clusters with distinct molecular signatures for the relevant pathways and cell subsets. Cluster 2, with low-grade inflammation, showed a better response to rituximab therapy than cluster 1, with high-grade inflammation. Fourteen key driver genes appeared to be essential signaling mediators downstream of the B cell receptor (BCR) signaling pathway and to have a positive relationship with histopathology scores.

Conclusion

Integrative network-based approaches provide deep insights into the modules and pathways causally related to SjS and allow identification of key targets for disease. Intervention adjusted to the molecular traits of the disease would allow the achievement of better outcomes, and the BCR signaling pathway and its leading players are promising therapeutic targets.

Machine learning-based prediction of radiographic progression in patients with axial spondyloarthritis

INTRODUCTION

Machine learning is applied to characterize the risk and predict outcomes in multi-dimensional data. The prediction of radiographic progression in axial spondyloarthritis (axSpA) remains limited. Hence, we tested the feasibility of supervised machine learning algorithms to predict radiographic progression in axSpA.

METHODS

This is a retrospective and hospital-based study. Clinical and laboratory data obtained from two independent axSpA groups were used as training and testing datasets. Radiographic progression over 2 years was assessed using the modified Stoke Ankylosing Spondylitis Spine Score (mSASSS) and mSASSS worsening by ≥ two units was defined as progression. Seven machine learning models with different algorithms were fitted, and their performance for the testing dataset was assessed using receiver-operating characteristic (ROC) and precision-recall (PR) curve.

RESULTS

The training and testing groups had equivalent characteristics, and radiographic progression was identified in 25.3% and 23.7%, respectively. The generalized linear model (GLM) and support vector machine (SVM) were the top two best-performing models with an average area-under-curve (AUC) of ROC of over 0.78. SVM had the higher AUC of PR compared with GLM (0.56 versus 0.51). Balanced accuracy was over 65% in all models. mSASSS was the most informative variable, followed by the presence of syndesmophyte(s) at the baseline and sacroiliac joint grades.

CONCLUSIONS

Clinical and radiographic data-driven predictive models showed reasonable performance in the prediction of radiographic progression in axSpA. Further modelling with larger and more detailed data could provide an excellent opportunity for the clinical translation of the predictive models to the management of high-risk patients.Key Points• Clinical and radiographic data-driven predictive models showed reasonable performance in the prediction of radiographic progression in axSpA.• Further modelling with larger and more detailed data could provide an excellent opportunity for the clinical translation of the predictive models to the management of high-risk patients.

Respiratory viral infections and the risk of rheumatoid arthritis

Background

We aimed to investigate the effects of ambient respiratory viral infections in the general population on rheumatoid arthritis (RA) development.

Methods

Data of weekly incident RA (2012–2013) were obtained from the Korean National Health Insurance claims database, and those of weekly observations on eight respiratory viral infections were obtained from the Korea Centers for Disease Control and Prevention database. We estimated the percentage change in incident RA associated with ambient mean respiratory viral infections using a generalized linear model, after adjusting for time trend, air pollution, and meteorological data.

Results

A total of 24,117 cases of incident RA (mean age 54.7 years, 18,688 [77.5%] women) were analyzed. Ambient respiratory viral infections in the population were associated with a higher number of incident RA over time, and its effect peaked 6 or 7 weeks after exposure. Among the 8 viruses, parainfluenza virus (4.8% for 1% respiratory viral infection increase, 95% CI 1.6 to 8.1, P = .003), coronavirus (9.2%, 3.9 to 14.8, P < .001), and metapneumovirus (44%, 2.0 to 103.4, P = .038) were associated with increased number of incident RA. The impact of these respiratory viral infections remained significant in women (3.8%, 12.1%, and 67.4%, respectively, P < .05) and in older patients (10.7%, 14.6%, and 118.2%, respectively, P < .05).

Conclusions

Ambient respiratory viral infections in the population were associated with an increased number of incident RA, especially in women and older patients, suggesting that respiratory viral infections can be a novel environmental risk factor for the development of RA.

Electronic supplementary material

The online version of this article (10.1186/s13075-019-1977-9) contains supplementary material, which is available to authorized users.

Application of machine learning in rheumatic disease research

Over the past decade, there has been a paradigm shift in how clinical data are collected, processed and utilized. Machine learning and artificial intelligence, fueled by breakthroughs in high-performance computing, data availability and algorithmic innovations, are paving the way to effective analyses of large, multi-dimensional collections of patient histories, laboratory results, treatments, and outcomes. In the new era of machine learning and predictive analytics, the impact on clinical decision-making in all clinical areas, including rheumatology, will be unprecedented. Here we provide a critical review of the machine-learning methods currently used in the analysis of clinical data, the advantages and limitations of these methods, and how they can be leveraged within the field of rheumatology.

Association of cumulative anti-cyclic citrullinated protein antibodies with radiographic progression in patients with rheumatoid arthritis

INTRODUCTION

Antibody against cyclic citrullinated protein (ACPA) is counted as one of the most important biomarkers in diagnosis, classification, and prognosis of rheumatoid arthritis (RA). We examined the evolution of ACPA during disease course and assess predictive value of time-weighted cumulative ACPA titer on radiographic progression in RA patients.

METHOD

A group of 734 patients with RA was followed longitudinally over 2 years, with annual measurements of ACPA. The cumulative titers of ACPA were calculated using the trapezoidal rule and were divided into three categories: negative, low-to-moderate, and high. Radiographs of the hands were scored with the modified Sharp score (SHS). Multivariable logistic regression models were performed to identify independent predictors over follow-up for individual patients with different combinations of risk factors. The effect size was computed by Cohen's d method.

RESULTS

The patients with radiographic progression had a higher SHS at baseline; and smoking status, diabetes, RF positivity, and use of biologic DMARDs were independently associated with radiographic progression (all P < 0.05). As for ACPA, reversion happened more commonly in men and was associated with younger onset age and lower titer at baseline, but it had no direct relevance to radiographic outcome. In multivariable regression analysis, only high cumulative or baseline titer of ACPA had a predictive power for rapid radiographic progression (all P < 0.05), and cumulative ACPA titer was superior in terms of statistical significance (Cohen's d, 0.637 versus 0.583).

CONCLUSIONS

High cumulative ACPA titer was independently associated with accelerated radiographic progression, especially with initiation of joint damage.

Compendium of skin molecular signatures identifies key pathological features associated with fibrosis in systemic sclerosis

Objectives

Treatment of patients with systemic sclerosis (SSc) can be challenging because of clinical heterogeneity. Integration of genome-scale transcriptomic profiling for patients with SSc can provide insights on patient categorisation and novel drug targets.

Methods

A normalised compendium was created from 344 skin samples of 173 patients with SSc, covering an intersection of 17 424 genes from eight data sets. Differentially expressed genes (DEGs) identified by three independent methods were subjected to functional network analysis, where samples were grouped using non-negative matrix factorisation. Finally, we investigated the pathways and biomarkers associated with skin fibrosis using gene-set enrichment analysis.

Results

We identified 1089 upregulated DEGs, including 14 known genetic risk factors and five potential drug targets. Pathway-based subgrouping revealed four distinct clusters of patients with SSc with distinct activity signatures for SSc-relevant pathways. The inflammatory subtype was related to significant improvement in skin fibrosis at follow-up. The phosphoinositide-3-kinase-protein kinase B (PI3K-Akt) signalling pathway showed both the closest correlation and temporal pattern to skin fibrosis score. COMP, THBS1, THBS4, FN1, and TNC were leading-edge genes of the PI3K-Akt pathway in skin fibrogenesis.

Conclusions

Construction and analysis of normalised skin transcriptomic compendia can provide useful insights on pathway involvement by SSc subsets and discovering viable biomarkers for a skin fibrosis index. Particularly, the PI3K-Akt pathway and its leading players are promising therapeutic targets.

Association between long-term exposure of ambient air pollutants and cardiometabolic diseases: A 2012 Korean Community Health Survey

BACKGROUND AND AIM

The associations of long-term exposure to particulate matter <10 μm in size (PM₁₀), nitrogen dioxide (NO₂), carbon monoxide (CO), sulfur dioxide (SO₂), and ozone (O₃) with cardiometabolic diseases (CMD) remain uncertain in the Korean population. Therefore, we sought to examine the associations between PM₁₀, NO₂, CO, SO₂, and O₃ and CMD using data collected from the Korean Community Health Survey.

METHODS AND RESULTS

We selected 100,867 adults aged 19 years or older who had lived in the same domicile for ≥10 years and surveyed them to collect data on socioeconomic characteristics; health-related behaviors; obesity; and physician-diagnosed CMD history, including hypertension, diabetes mellitus, dyslipidemia, stroke, myocardial infarction, and ischemic heart disease. We calculated interquartile ranges for PM₁₀, NO₂, CO, SO₂, and O₃ from the 10 year average concentrations (2003-2012). Hypertension, diabetes mellitus, and dyslipidemia were positively associated with PM₁₀, NO₂, CO, SO₂, and O₃ after adjusting for confounding factors. Obesity was positively associated with PM₁₀, NO₂, SO₂, and O₃. On the other hand, we found no associations between stroke, myocardial infarction, and ischemic heart disease and exposure to PM₁₀, NO₂, CO, SO₂, and O₃ in these subjects. In subjects aged ≥65 years, the risk of dyslipidemia was markedly increased under exposure to NO₂ and CO compared to subjects aged <65 years. The risk of obesity was also significantly increased under exposure to PM₁₀ and NO₂. However, sex differences in these associations were not found.

CONCLUSION

Long-term exposure to PM₁₀, NO₂, CO, SO₂, and O₃ may be a risk factor of CMD in Korean adults.

The relationship between clinical characteristics including presence of exposed lesions and health-related quality of life (HRQoL) in patients with psoriasis: analysis from the nationwide epidemiologic study for psoriasis in Korea (EPI-PSODE study)

BACKGROUND

Psychological aspect and quality of life should be considered in treating patients with psoriasis.

OBJECTIVE

We sought to ascertain which clinical characteristics including presence of exposed lesions are associated with impairment of health-related quality of life (HRQoL) in patients with psoriasis.

METHODS

The EPI-PSODE study was a nationwide, multicenter, cross-sectional study conducted in Korea that included 1260 adult patients with psoriasis. In addition to clinical characteristics including presence of exposed lesions, data were collected using the Psoriatic Arthritis (PsA) Screening and Evaluation (PASE), Dermatology Life Quality Index (DLQI), MOS 36-Item Short-Form Health Survey (SF-36), Work Productivity and Activity Impairment Questionnaire Psoriasis (WPAI: PSO) and Medication Satisfaction Questionnaire (MSQ).

RESULTS

Patients with a DLQI score > 5 (n = 990) were younger, had an earlier onset of psoriasis, scored higher on the Psoriasis Area and Severity Index (PASI), had higher body surface area (BSA) and had higher PASE scores than patients with DLQI ≤ 5 (n = 266). The group of patients with exposed lesions (n = 871) were younger and male predominance, earlier onset of psoriasis, longer disease duration, higher PASI/BSA score and a higher proportion with drinking and smoking history each than the group of patients without exposed lesions (n = 389). Presence of exposed lesions negatively influenced DLQI, 36-Item Short-Form Health Survey (SF-36) (mental component), presenteeism, total work productivity impairment and total activity impairment in the WPAI: PSO. In multiple regression model, PASI score was the only variable which was significantly associated with all HRQoL measures. Presence of exposed lesions was a significant factor affecting DLQI and SF-36 (mental).

CONCLUSION

The presence of exposed lesions has a negative impact on quality of life, mental health and work productivity. Therefore, effective treatments are particularly needed for psoriasis patients with exposed lesions.

Elevated levels of soluble CD40 ligand are associated with antiphospholipid antibodies in patients with systemic lupus erythematosus

OBJECTIVES

The CD40L/CD40 pathway is involved in the pathophysiology of atherothrombotic disease, and elevated levels of soluble CD40L (sCD40L) were reported in SLE patients. However, the clinical implication of sCD40L in SLE remains elusive.

METHODS

We measured levels of plasma sCD40L in 241 SLE patients and 37 healthy controls and investigated its association with clinical manifestation and laboratory parameters.

RESULTS

Levels of plasma sCD40L in SLE patients were significantly elevated compared with healthy controls (p=0.013) and positively correlated with levels of soluble P-selectin (γ=0.336, p<0.001). SLE patients who experienced arterial thrombosis had a higher level of sCD40L than those who did not (p=0.029). Plasma sCD40L levels were positively correlated with the titers of anti-cardiolipin and anti-β2 glycoprotein I antibodies (γ=0.338, p<0.001 and γ=0.364, p<0.001, respectively). Its levels were also significantly higher in patients with clinical antiphospholipid syndrome (APS) than in non-APS patients, irrespective of antiphospholipid antibody (aPL) positivity. Of those with arterial thrombosis, sCD40L levels were significantly elevated in patients with positive aPL, compared to those with negative aPL (p=0.011). Multiple regression analysis revealed that the presence of hypertension and positive aPL were independently associated with the occurrence of arterial thrombosis in SLE patients. A parallel analysis showed that sCD40L was also an independent variable for arterial thrombosis; however, this association disappeared when aPL, a strong variable, was included in the model because of collinearity between aPL and sCD40L.

CONCLUSIONS

Plasma sCD40L levels were elevated in SLE patients who had positive aPL and experienced arterial thrombosis, suggesting that enhanced release of sCD40L through platelet activation presumably by aPL could contribute to the development of atherothrombotic disease.

Integration of piezo-capacitive and piezo-electric nanoweb based pressure sensors for imaging of static and dynamic pressure distribution

Recently, highly flexible and soft pressure distribution imaging sensor is in great demand for tactile sensing, gait analysis, ubiquitous life-care based on activity recognition, and therapeutics. In this study, we integrate the piezo-capacitive and piezo-electric nanowebs with the conductive fabric sheets for detecting static and dynamic pressure distributions on a large sensing area. Electrical impedance tomography (EIT) and electric source imaging are applied for reconstructing pressure distribution images from measured current-voltage data on the boundary of the hybrid fabric sensor. We evaluated the piezo-capacitive nanoweb sensor, piezo-electric nanoweb sensor, and hybrid fabric sensor. The results show the feasibility of static and dynamic pressure distribution imaging from the boundary measurements of the fabric sensors.

Increased risk of thyroid diseases in patients with systemic lupus erythematosus: A nationwide population-based Study in Korea

We investigated the association between autoimmune thyroid disease and systemic lupus erythematosus (SLE) using nationwide insurance claims data for the entire Korean population. Claims data for the period 2009-2013 were retrieved from the National Health Insurance System database. SLE and thyroid disease were identified using the International Classification of Diseases codes and medication information. Logistic regression analyses were used to evaluate the association between SLE and thyroid disease. The study used records from 17,495 patients with SLE and 52,485 age- and sex-matched control subjects. A greater prevalence of Graves' disease (0.94% vs. 0.46%, P < 0.001), Hashimoto's thyroiditis (2.68% vs. 0.80%, P < 0.001), and thyroid cancer (1.81% vs. 1.30%, P < 0.001) was observed in SLE patients than in control subjects. Multivariate regression analyses demonstrated that SLE was significantly associated with an increased risk of both autoimmune thyroid disease and thyroid cancer (Graves' disease: odds ratio [OR] 2.07, 95% confidence interval [CI] 1.70-2.53; Hashimoto's thyroiditis: OR 3.42, 95% CI 3.00-3.91; thyroid cancer: OR 1.40, 95% CI 1.22-1.60). Age- and sex- stratified analyses revealed that the risk of autoimmune thyroid disease in SLE patients was increased for all age groups and the female group. An association between thyroid cancer and SLE was identified only in the 20- to 59-year-old age group and in the female group. Using a large population-based study, we demonstrated that patients with SLE are at a greater risk of developing thyroid disease than matched control individuals.

Single-stage cell-based cartilage repair in a rabbit model: cell tracking and in vivo chondrogenesis of human umbilical cord blood-derived mesenchymal stem cells and hyaluronic acid hydrogel composite

OBJECTIVE

Human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) have gained popularity as a promising cell source for regenerative medicine, but limited in vivo studies have reported cartilage repair. In addition, the roles of MSCs in cartilage repair are not well-understood. The purpose of this study was to investigate the feasibility of transplanting hUCB-MSCs and hyaluronic acid (HA) hydrogel composite to repair articular cartilage defects in a rabbit model and determine whether the transplanted cells persisted or disappeared from the defect site.

DESIGN

Osteochondral defects were created in the trochlear grooves of the knees. The hUCB-MSCs and HA composite was transplanted into the defect of experimental knees. Control knees were transplanted by HA or left untreated. Animals were sacrificed at 8 and 16 weeks post-transplantation and additionally at 2 and 4 weeks to evaluate the fate of transplanted cells. The repair tissues were evaluated by gross, histological and immunohistochemical analysis.

RESULTS

Transplanting hUCB-MSCs and HA composite resulted in overall superior cartilage repair tissue with better quality than HA alone or no treatment. Cellular architecture and collagen arrangement at 16 weeks were similar to those of surrounding normal articular cartilage tissue. Histological scores also revealed that cartilage repair in experimental knees was better than that in control knees. Immunohistochemical analysis with anti-human nuclear antibody confirmed that the transplanted MSCs disappeared gradually over time.

CONCLUSION

Transplanting hUCB-MSCs and HA composite promote cartilage repair and interactions between hUCB-MSCs and host cells initiated by paracrine action may play an important role in cartilage repair.

Licoricidin, an isoflavonoid isolated from Glycyrrhiza uralensis Fisher, prevents UVA-induced photoaging of human dermal fibroblasts

OBJECTIVE

Licoricidin is an isoflavonoid isolated from Glycyrrhiza uralensis Fisher. In this study, we investigated the effects of licoricidin on photoaging of UVA-irradiated human dermal fibroblasts (HDFs).

METHODS

In vitro reactive oxygen species (ROS) scavenging activity, cellular protective effect and inhibition of elastase activity was determined by Fe³⁺ -EDTA/H₂ O₂ systems, photohaemolysis and elastase activity assay, respectively. Anti-oxidative capacity of the compound was evaluated by fluorescent ELISA and 2', 7'-dichlorofluorescin-diacetate (DCF-DA) assay. The expression of protein and phosphorylation was examined using Western blot.

RESULTS

The ROS scavenging activity (OSC₅₀ ) of licoricidin was 2.77 μM. It was 3.1-fold higher than that of L-ascorbic acid. Its protective effects were confirmed in a study of ¹ O₂ -induced cellular damage to human erythrocytes. The τ₅₀ value of 10 μM of licoricidin was 71.0 min; this was markedly higher than that obtained with α-tocopherol (37.0 min). The elastase inhibitory activity of licoricidin (IC₅₀ of 61.2 μM) was 2.1-fold more potent than that of oleanolic acid. Licoricidin markedly reduced the UVA-induced intracellular ROS in a concentration-dependent manner. Western blot revealed that licoricidin attenuated the UVA-dependent induction of MMP-1 protein. Mechanistically, this appeared to be due to licoricidin-dependent inhibition of mitogen-activated protein kinases (MAPK) phosphorylation, which resulted in decreased c-Jun activation and reduced c-Jun and c-Fos expression.

CONCLUSION

Licoricidin blocks UVA-induced photoaging via ROS scavenging. This activity converges to limit the activity of MMP-1. These data suggest that licoricidin may be considered as an active ingredient in new topically applied anti-ageing formulations.

Association of inflammatory bowel disease with ankylosing spondylitis and rheumatoid arthritis: A nationwide population-based study

OBJECTIVES

Tantalizing connections between autoimmune rheumatic diseases (ARDs) and inflammatory bowel disease (IBD) have become evident with regard to their genetic and immunologic background. However, the association between these two disease entities remains unclear. The aim of this study is to investigate the association between each ARD and IBD.

METHODS

A nationwide population-based cross-sectional study was performed using the Korean National Health Insurance Claims database. The data of patients with IBD and age- and sex-matched controls between 2009 and 2013 were collected from the database. The prevalence of ARDs, including systemic lupus erythematosus (SLE), inflammatory myositis (polymyositis and dermatomyositis), systemic sclerosis (SSc), Sjögren's syndrome (SjS), ankylosing spondylitis (AS), and rheumatoid arthritis (RA), was determined. The associations between each ARD and IBD were analyzed using multivariate logistic regression models.

RESULTS

A total of 40,843 IBD patients (28,197 patients with ulcerative colitis and 12,646 with Crohn's disease) and 122,529 controls were enrolled. The nonstratified analysis revealed that patients with IBD had significant risk of being concomitantly affected by AS (odds ratio [OR] 5.140, 95% confidence interval [95% CI] 4.069-6.492) and RA (OR: 3.474, 95% CI: 2.671-4.519) after adjusting for age and sex. No significant association was observed between IBD and other ARDs including SLE, inflammatory myositis, SSc, and SjS.

CONCLUSION

IBD is significantly associated with AS and RA in the large-scaled population-based study. This result suggests that etiopathogenesis of IBD might be shared with AS and RA.

Association of Anemic Hypoxia and Increased Pulmonary Artery Systolic Pressure in Patients With Systemic Lupus Erythematosus

OBJECTIVE

Pulmonary arterial hypertension (PAH) is a rare but serious complication of systemic lupus erythematosus (SLE). Chronic hypoxia is known to cause PAH resulting from pulmonary vascular remodeling. We investigated the association between anemic hypoxia and PAH in SLE patients.

METHODS

Systolic pulmonary artery pressure (PAP) was measured in 132 SLE patients by echocardiography. Increased PAP was defined as resting PAP > 40 mm Hg. Oxygen delivery (DO2) was estimated as the product of cardiac output and arterial oxygen content.

RESULTS

Of 132 patients, 17 (12.9%) had increased PAP, and these patients had significantly lower DO2 values than patients with normal PAP (P = 0.002). The DO2 values inversely correlated with PAP values (γ = -0.308, P < 0.001) and plasma N-terminal pro-brain natriuretic peptide levels (γ = -0.323, P = 0.001), but positively correlated with hemoglobin levels (γ = 0.402, P < 0.001). Compared to those with normal PAP, patients with increased PAP had significantly longer durations of anemia over the preceding 6-24 months. Patients with anemia of longer durations (≥3 months) in the preceding 6 months had a higher risk of increased PAP compared to those with shorter durations (P < 0.001). When SLE patients were divided into 3 groups according to hemoglobin and PAP, serum interleukin-6 (IL-6) levels increased across groups with higher PAP (P = 0.001 for trend), but decreased across tertiles of hemoglobin levels (P = 0.008 for trend).

CONCLUSION

Our data indicate an association between chronic anemic hypoxia and increased PAP in SLE patients and suggest that increased IL-6 might participate in this process.

C9orf72 is required for proper macrophage and microglial function in mice

Expansions of a hexanucleotide repeat (GGGGCC) in the noncoding region of the C9orf72 gene are the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia. Decreased expression of C9orf72 is seen in expansion carriers, suggesting that loss of function may play a role in disease. We found that two independent mouse lines lacking the C9orf72 ortholog (3110043O21Rik) in all tissues developed normally and aged without motor neuron disease. Instead, C9orf72 null mice developed progressive splenomegaly and lymphadenopathy with accumulation of engorged macrophage-like cells. C9orf72 expression was highest in myeloid cells, and the loss of C9orf72 led to lysosomal accumulation and altered immune responses in macrophages and microglia, with age-related neuroinflammation similar to C9orf72 ALS but not sporadic ALS human patient tissue. Thus, C9orf72 is required for the normal function of myeloid cells, and altered microglial function may contribute to neurodegeneration in C9orf72 expansion carriers.

Removal ratio of gaseous toluene and xylene transported from air to root zone via the stem by indoor plants

This work was designed to investigate the removal efficiency as well as the ratios of toluene and xylene transported from air to root zone via the stem and by direct diffusion from the air into the medium. Indoor plants (Schefflera actinophylla and Ficus benghalensis) were placed in a sealed test chamber. Shoot or root zone were sealed with a Teflon bag, and gaseous toluene and xylene were exposed. Removal efficiency of toluene and total xylene (m, p, o) was 13.3 and 7.0 μg·m(-3)·m(-2) leaf area over a 24-h period in S. actinophylla, and was 13.0 and 7.3 μg·m(-3)·m(-2) leaf area in F. benghalensis. Gaseous toluene and xylene in a chamber were absorbed through leaf and transported via the stem, and finally reached to root zone, and also transported by direct diffusion from the air into the medium. Toluene and xylene transported via the stem was decreased with time after exposure. Xylene transported via the stem was higher than that by direct diffusion from the air into the medium over a 24-h period. The ratios of toluene transported via the stem versus direct diffusion from the air into the medium were 46.3 and 53.7% in S. actinophylla, and 46.9 and 53.1% in F. benghalensis, for an average of 47 and 53% for both species. The ratios of m,p-xylene transported over 3 to 9 h via the stem versus direct diffusion from the air into the medium was 58.5 and 41.5% in S. actinophylla, and 60.7 and 39.3% in F. benghalensis, for an average of 60 and 40% for both species, whereas the ratios of o-xylene transported via the stem versus direct diffusion from the air into the medium were 61 and 39%. Both S. actinophylla and F. benghalensis removed toluene and xylene from the air. The ratios of toluene and xylene transported from air to root zone via the stem were 47 and 60 %, respectively. This result suggests that root zone is a significant contributor to gaseous toluene and xylene removal, and transported via the stem plays an important role in this process.

SATB2-associated syndrome presenting with Rett-like phenotypes

The SATB2-associated syndrome (SAS) was proposed recently, after the SATB2 gene was initially discovered to be associated with isolated cleft palate. This syndrome is characterized by intellectual disability with delayed speech development, facial dysmorphism, cleft or high-arched palate, and dentition problems. Here, we describe two novel SATB2 sequence variants in two unrelated patients presenting with Rett-like phenotypes. We performed trio-based whole-exome sequencing in a 17-month-old girl presenting with severe retardation and Rett-like phenotypes, which revealed a de novo missense variant in SATB2 (p.Glu396Gln). Moreover, targeted sequencing of the SATB2 gene was performed in a 2-year-old girl with severe psychomotor retardation, facial hypotonia, and cleft palate who also exhibited some features of Rett syndrome. A nonsense variant in SATB2 was identified in this patient (p.Arg459*). This study expanded the clinical and genetic spectrum of SAS. SATB2 variants should be considered in cases with psychomotor retardation alone or in any cases with Rett-like phenotypes, regardless of the typical features of SAS such as cleft palate.

Development of an optimized Compton suppression gamma-ray spectrometric system using Monte Carlo simulation

We have chosen to establish the Compton Suppression Spectrometer (CSS) for low activity environmental samples with a high purity germanium (HPGe) primary detector and a removable plug-in detector (NaI(Tl)) surrounded with a cylindrical annulus guard detector (NaI(Tl)). Monte Carlo simulation with PENELOPE (PENetration and Energy LOss of Positrons and Electrons) is used to determine the optimal geometry of the CSS. To verify a correlation between experiment and simulation, the energy distribution of (137)Cs and (60)Co point sources is measured and simulated for each condition. The CSS parameters are studied to determine optimal detector geometry and Compton Suppression Factor (CSF). The timing resolution of the CSS was found to be 44ns (FWHM), which is an outstanding result in the semiconductor-based gamma-ray spectrometry. All measured values of CSF agree within 5% with the values obtained from the simulation. The optimum geometry and CSF values are discussed.

Clinical significance of subclinical varicocelectomy in male infertility: systematic review and meta-analysis

Recent meta-analysis by the Cochrane collaboration concluded that treatment of varicocele may improve an infertile couple's chance of pregnancy. However, there has been no consensus on the management of subclinical varicocele. Therefore, we determine the impact of varicocele treatment on semen parameters and pregnancy rate in men with subclinical varicocele. The randomised controlled trials that assessed the presence and/or treatment of subclinical varicocele were included for systematic review and meta-analysis. Random effect model was used to calculate the weighted mean difference of semen parameters and odds ratio of pregnancy rates. Seven trials with 548 participants, 276 in subclinical varicocelectomy and 272 in no-treatment or clomiphene citrate subjects, were included. Although there was also no statistically significant difference in pregnancy rate (OR 1.29, 95% CI 0.99-1.67), surgical treatment resulted in statistically significant improvements on forward progressive sperm motility (MD 3.94, 95% CI 1.24-6.65). However, the evidence is not enough to allow final conclusions because the quality of included studies is very low and further research is needed.