Beta-adrenergic stimulation promotes an endoplasmic reticulum stress-dependent inflammatory program in salivary gland epithelial cells.

The effect of beta-adrenergic stimulation on human labial minor salivary gland epithelial cells (LMSGEC) on IL-6 production, and its dependency to endoplasmic reticulum (ER) stress were investigated. Primary LMSGEC from Sjögren's syndrome (SS) patients and controls in culture were stimulated with epinephrine and IL-6 expression was evaluated by qPCR and ELISA. The expression of ß-ARs in cultured LMSGEC was tested by qPCR, while adrenoceptors and cAMP levels were examined in LMSGs by immunofluorescence. ER evaluation was performed by Transmission electron microscopy (TEM) and ER stress by Western blot. Adrenergic induced IL-6 production by cultured LMSGEC was evaluated after alleviation of the ER stress by applying Tauroursodeoxycholic acid (TUDCA) and silencing of PKR-like ER kinase (PERK) and activating transcription factor 4 (ATF4) RNAs. Expression of IL-6 by LMSGEC was upregulated after ß-adrenergic stimulation, while the silencing of adrenoreceptors downregulated IL-6. The amelioration of ER stress, as well as the silencing of PERK/ATF4, prevented epinephrine-induced upregulation of IL-6. Adrenergic stimulation led to higher and sustained IL-6 levels secreted by LMSGEC of SS patients compared to controls. Adrenergic signaling was endogenously enhanced in LMSGEC of SS patients (expression of ß-ARs in situ, intracellular cAMP in cultured LMSGEC). In parallel, SS-LMSGEC expressed dilated ER (TEM) and higher levels of GRP78/BiP. PERK/ATF4 pathway of the ER stress emerged a considerable mediator of adrenergic stimulation for IL-6 production by the LMSGEC. An enhanced endogenous adrenergic activation and a stressed ER observed in SS-LMSGEC may contribute to a sustained IL-6 production by these cells after adrenergic stimulation.

Clinical and laboratory findings of primary Sjögren's syndrome patients without sicca symptoms.

OBJECTIVES: Primary Sjögren's syndrome (pSS) is a systemic autoimmune disease characterised by oral and eye dryness. A minority of patients can present without dryness but studies on their clinico-laboratory manifestations are scarce. Our purpose was to describe the clinical phenotype of pSS patients lacking sicca symptoms. METHODS: From a total of 1738 consecutive pSS patients fulfilling the 2016 ACR-EULAR criteria, those who presented without sicca symptoms were identified (non-dryness group). Their medical data was collected and compared with 2 control groups: a) the remaining unmatched sicca pSS patients with both oral and eye dryness (unmatched dryness group) and b) matched sicca pSS patients according to age, sex, and disease duration, in 1:2 ratio (matched dryness group). RESULTS: Thirty-eight (2.19%) patients lacked sicca manifestations presenting mainly with arthralgias (47%), parotid enlargement (24%), Raynaud's phenomenon (11%) and persistent lymphadenopathy (11%) that led them to be evaluated for pSS. Non-dryness pSS patients were younger than the unmatched sicca controls, displaying a higher frequency of anti-Ro/SSA antibodies (100% vs. 79.7%, p<0.001), ANA positivity (100% vs. 90.4%, p<0.001), neutropenia (20.8% vs. 7.5%, p=0.04) and thrombocytopenia (13.8% vs. 4.2%, p=0.04). They also had lower frequency of positive ocular tests compared to both unmatched and matched dryness patients. No differences were found between non-dryness pSS patients and both control groups regarding focus score or any other extraglandular manifestation. CONCLUSIONS: pSS patients without sicca complaints constitute a distinct phenotype involving younger patients, sharing common immunopathologic mechanisms with typical sicca patients.

COVID-19: Clinical features and outcomes in unvaccinated 2-dose and 3-dose vaccinated against SARS-CoV-2 patients with systemic autoimmune and autoinflammatory rheumatic diseases.

Clinical data on vaccinated patients with coronavirus disease 2019 (COVID-19) who have systemic autoimmune and autoinflammatory rheumatic diseases (SAARD) are limited. This observational study aimed to report the clinical features and outcomes of COVID-19 among cases with SAARD that were unvaccinated or were 2- and 3-dose vaccinated against SARS-CoV-2 and were consecutively recorded by the treating physician. Unvaccinated and 2- and 3-dose vaccinated patients were compared in terms of COVID-19 symptomatology, hospitalizations, oxygen supplementation requirements, and death rates. From the beginning of the pandemic to February 15, 2022, 134 vaccine-naïve COVID-19 cases were recorded among our study cohort. From March 1, 2021 to February 15, 2022, 89 2-dose vaccinated and 105 3-dose vaccinated patients who were infected with SARS-CoV-2 ≥14 days after the second dose were included. The hospitalization rate was higher in the unvaccinated (n = 36, 26.9%) than in the 2-dose (n = 13, 14.6%, p = 0.03) or 3-dose (n = 5, 4.8%, p < 0.001) vaccinated patients. Severe/critical COVID-19 cases requiring oxygen supplementation were the least among 3-dose vaccinated (n = 4, 3.8%) compared to both 2-dose vaccinated (n = 12, 13.5%, p = 0.018) and unvaccinated (n = 25, 18.7%, p < 0.001) patients. ICU admission and death rates were similar among unvaccinated (n = 5, 3.7% and n = 3, 2.2%, respectively) and 2-dose vaccinated patients (n = 4, 4.5%; and n = 2, 2.2%, respectively), while no 3-dose vaccinated patients died or required ICU admission. Logistic regression analysis revealed a significant inverse association between 3-dose vaccination and severe/critical COVID-19 (OR = 0.078, 95% CI: 0.022-0.273, p < 0.001). In conclusion, these findings argue in favor of booster vaccination against SARS-CoV-2 in patients with SAARD.

Addressing the clinical unmet needs in primary Sjögren's Syndrome through the sharing, harmonization and federated analysis of 21 European cohorts.

For many decades, the clinical unmet needs of primary Sjögren's Syndrome (pSS) have been left unresolved due to the rareness of the disease and the complexity of the underlying pathogenic mechanisms, including the pSS-associated lymphomagenesis process. Here, we present the HarmonicSS cloud-computing exemplar which offers beyond the state-of-the-art data analytics services to address the pSS clinical unmet needs, including the development of lymphoma classification models and the identification of biomarkers for lymphomagenesis. The users of the platform have been able to successfully interlink, curate, and harmonize 21 regional, national, and international European cohorts of 7,551 pSS patients with respect to the ethical and legal issues for data sharing. Federated AI algorithms were trained across the harmonized databases, with reduced execution time complexity, yielding robust lymphoma classification models with 85% accuracy, 81.25% sensitivity, 85.4% specificity along with 5 biomarkers for lymphoma development. To our knowledge, this is the first GDPR compliant platform that provides federated AI services to address the pSS clinical unmet needs.

A prospective multicenter study assessing humoral immunogenicity and safety of the mRNA SARS-CoV-2 vaccines in Greek patients with systemic autoimmune and autoinflammatory rheumatic diseases.

OBJECTIVES: To investigate humoral responses and safety of mRNA SARS-CoV-2 vaccines in systemic autoimmune and autoinflammatory rheumatic disease (SAARD) patients subjected or not to treatment modifications during vaccination. METHODS: A nationwide, multicenter study, including 605 SAARD patients and 116 controls, prospectively evaluated serum anti-SARS-CoV-2 S1-protein IgG antibody titers, side-effects, and disease activity, one month after complete vaccination, in terms of distinct treatment modification strategies (none, partial and extended modifications). Independent risk factors associated with hampered humoral responses were identified by data-driven multivariable logistic regression analysis. RESULTS: Patients with extended treatment modifications responded to vaccines similarly to controls as well as SAARD patients without immunosuppressive therapy (97.56% vs 100%, p = 0.2468 and 97.56% vs 97.46%, p > 0.9999, respectively). In contrast, patients with partial or without therapeutic modifications responded in 87.50% and 84.50%, respectively. Furthermore, SAARD patients with extended treatment modifications developed higher anti-SARS-CoV-2 antibody levels compared to those without or with partial modifications (median:7.90 vs 7.06 vs 7.1, p = 0.0003 and p = 0.0195, respectively). Mycophenolate mofetil (MMF), rituximab (RTX) and methotrexate (MTX) negatively affected anti-SARS-CoV-2 humoral responses. In 10.5% of vaccinated patients, mild clinical deterioration was noted; however, no differences in the incidence of deterioration were observed among the distinct treatment modification SAARD subgroups. Side-effects were generally comparable between SAARD patients and controls. CONCLUSIONS: In SAARD patients, mRNA SARS-CoV-2 vaccines are effective and safe, both in terms of side-effects and disease flares. Treatment with MMF, RTX and/or MTX compromises anti-SARS-CoV-2 antibody responses, which are restored upon extended treatment modifications without affecting disease activity.

Combined seronegativity in Sjögren's syndrome.

OBJECTIVES: To describe the clinical spectrum of Sjögren's syndrome (SS) patients with combined seronegativity. METHODS: From a multicentre study population of consecutive SS patients fulfilling the 2016 ACR-EULAR classification criteria, patients with triple seronegativity [anti-Ro/SSA(-), anti-La/SSB(-), RF(-) and ANA(+)] and quadruple seronegativity [anti-Ro/SSA(-), anti-La/SSB(-), RF(-) and ANA(-)] were identified retrospectively. Both groups were matched in an 1:1 ratio with 2 distinct control SS groups: i) classic anti-Ro/SSA seropositive patients [SS(+)] and ii) classic anti-Ro/SSA seropositive patients with negative rheumatoid factor [SS(+)/RF(-)] to explore their effect on disease expression. Clinical, laboratory and, histologic features were compared. A comparison between triple and quadruple seronegative SS patients was also performed. REESULTS: One hundred thirty-five SS patients (8.6%) were identified as triple seronegative patients and 72 (4.5%) as quadruple. Triple seronegative patients had lower frequency of peripheral nervous involvement (0% vs. 7.2% p=0.002) compared to SS(+) controls and lower frequency of interstitial renal disease and higher prevalence of dry mouth than SS(+)/RF(-) controls. Quadruple seronegative patients presented less frequently with persistent lymphadenopathy (1.5% vs. 16.9 p=0.004) and lymphoma (0% vs. 9.8% p=0.006) compared to SS(+) controls and with lower prevalence of persistent lymphadenopathy (1.5% vs. 15.3% p=0.008) and higher frequency of dry eyes (98.6% vs. 87.5% p=0.01) and autoimmune thyroiditis (44.1% vs. 17.1% p=0.02) compared to SS(+)/RF(-) SS controls. Study groups comparative analysis revealed that triple seronegative patients had higher frequency of persistent lymphadenopathy and lymphoma, higher focus score and later age of SS diagnosis compared to quadruple seronegative patients. CONCLUSIONS: Combined seronegativity accounts for almost 9% of total SS population and is associated with a milder clinical phenotype, partly attributed to the absence of rheumatoid factor.

COVID-19 infection among autoimmune rheumatic disease patients: Data from an observational study and literature review.

The impact of SARS-CoV-2 infection in patients with autoimmune/auto-inflammatory rheumatic diseases (AARD) under immunomodulatory treatment has been a focus of interest during the COVID-19 pandemic. In this observational study, demographic data, disease related features and comorbidities, COVID-19 manifestations and outcome as well as antibody responses to SARS-CoV-2 were recorded among 77 consecutive patients with underlying AARD infected by SARS-CoV-2. Analysis of data was performed using univariate and multivariate models. Most patients (68.8%) had a mild COVID-19 course. The predominant clinical manifestations were fatigue (58.4%), low grade fever (45.4%) and upper respiratory tract symptoms (68.8%). About a quarter of patients required hospitalization (23.3%) and the mortality rate was 1.3%. Regarding COVID-19 severity, prior treatment with corticosteroids, mycophenolate mofetil or rituximab was more common in patients who developed a more serious disease course (60.0 vs 29.9%, p = 0.003, 40.0 vs 7.5%, p = 0.003, 10.0 vs 0.0%, p = 0.009, respectively). When disease related features and comorbidities were considered in multivariate models, older age and lung disease in the context of the AARD were found to be independent predictive factors for hospitalization (OR [95%]: 1.09 [1.03-1.15] and 6.43 [1.11-37.19]). Among COVID-19 related features, patients with shortness of breath and high-grade fever were more likely to get hospitalized (OR [95%]: 7.06 [1.36-36.57], 12.04 [2.96-48.86]), while anosmia was independently associated with lower hospitalization risk (OR [95%]: 0.09 [0.01-0.99]). Though the majority of AARD patients displayed a mild COVID-19 course, certain underlying disease features and COVID-19 related manifestations should prompt alertness for the physician to identify patients with AARD at high risk for severe COVID-19 and need for hospitalization.

A biomarker for lymphoma development in Sjogren's syndrome: Salivary gland focus score.

The aim of this study is to explore the role of labial minor salivary gland (LMSG) focus score (FS) in stratifying Sjögren's Syndrome (SS) patients, lymphoma development prediction and to facilitate early lymphoma diagnosis. Ιn an integrated cohort of 1997 patients, 618 patients with FS ≥ 1 and at least one-year elapsing time interval from SS diagnosis to lymphoma diagnosis or last follow up were identified. Clinical, laboratory and serological features were recorded. A data driven logistic regression model was applied to identify independent lymphoma associated risk factors. Furthermore, a FS threshold maximizing the difference of time interval from SS until lymphoma diagnosis between high and low FS lymphoma subgroups was investigated, to develop a follow up strategy for early lymphoma diagnosis. Of the 618 patients, 560 were non-lymphoma SS patients while the other 58 had SS and lymphoma. FS, cryoglobulinemia and salivary gland enlargement (SGE) were proven to be independent lymphoma associated risk factors. Lymphoma patients with FS ≥ 4 had a statistically significant shorter time interval from SS to lymphoma diagnosis, compared to those with FS < 4 (4 vs 9 years, respectively, p = 0,008). SS patients with FS ≥ 4 had more frequently B cell originated manifestations and lymphoma, while in patients with FS < 4, autoimmune thyroiditis was more prevalent. In the latter group SGE was the only lymphoma independent risk factor. A second LMSG biopsy is patients with a FS ≥ 4, 4 years after SS diagnosis and in those with FS < 4 and a history of SGE, at 9-years, may contribute to an early lymphoma diagnosis. Based on our results we conclude that LMSG FS, evaluated at the time of SS diagnosis, is an independent lymphoma associated risk factor and may serve as a predictive biomarker for the early diagnosis of SS-associated lymphomas.

Primary Sjögren's Syndrome of Early and Late Onset: Distinct Clinical Phenotypes and Lymphoma Development.

Objectives: To study the clinical, serological and histologic features of primary Sjögren's syndrome (pSS) patients with early (young ≤35 years) or late (old ≥65 years) onset and to explore the differential effect on lymphoma development. Methods: From a multicentre study population of 1997 consecutive pSS patients, those with early or late disease onset, were matched and compared with pSS control patients of middle age onset. Data driven analysis was applied to identify the independent variables associated with lymphoma in both age groups. Results: Young pSS patients (19%, n = 379) had higher frequency of salivary gland enlargement (SGE, lymphadenopathy, Raynaud's phenomenon, autoantibodies, C4 hypocomplementemia, hypergammaglobulinemia, leukopenia, and lymphoma (10.3% vs. 5.7%, p = 0.030, OR = 1.91, 95% CI: 1.11-3.27), while old pSS patients (15%, n = 293) had more frequently dry mouth, interstitial lung disease, and lymphoma (6.8% vs. 2.1%, p = 0.011, OR = 3.40, 95% CI: 1.34-8.17) compared to their middle-aged pSS controls, respectively. In young pSS patients, cryoglobulinemia, C4 hypocomplementemia, lymphadenopathy, and SGE were identified as independent lymphoma associated factors, as opposed to old pSS patients in whom SGE, C4 hypocomplementemia and male gender were the independent lymphoma associated factors. Early onset pSS patients displayed two incidence peaks of lymphoma within 3 years of onset and after 10 years, while in late onset pSS patients, lymphoma occurred within the first 6 years. Conclusion: Patients with early and late disease onset constitute a significant proportion of pSS population with distinct clinical phenotypes. They possess a higher prevalence of lymphoma, with different predisposing factors and lymphoma distribution across time.

Lessons of the month: Reemergence of rheumatic fever after a systemic streptococcal A infection: The role of cardiac MRI on the diagnosis of subclinical rheumatic carditis.

A 42-year-old man presented with fever, sore throat, rash and painful right knee swelling, preceded by self-medication with oral steroids. Blood and knee cultures yielded group A Streptococcus After 2 weeks of intravenous antibiotics and two arthroscopic knee debridements, he continued to experience spiking fevers, and electrocardiographic changes developed. We postulate that the patient suffered from the first presentation of acute rheumatic fever, following an invasive group A bacteraemic streptococcal infection. The possible role of cardiac magnetic resonance imaging in the diagnosis of rheumatic carditis is discussed.

Rheumatoid arthritis patients on persistent moderate disease activity on biologics have adverse 5-year outcome compared to persistent low-remission status and represent a heterogeneous group.

BACKGROUND: The long-term outcome of rheumatoid arthritis (RA) patients who in clinical practice exhibit persistent moderate disease activity (pMDA) despite treatment with biologics has not been adequately studied. Herein, we analyzed the 5-year outcome of the pMDA group and assessed for within-group heterogeneity. METHODS: We included longitudinally monitored RA patients from the Hellenic Registry of Biologic Therapies with persistent (cumulative time ≥ 50% of a 5-year period) moderate (pMDA, 3.2 < DAS28 ≤ 5.1) or remission/low (pRLDA, DAS28 ≤ 3.2) disease activity. The former was further classified into persistent lower-moderate (plMDA, DAS28 < 4.2) and higher-moderate (phMDA, DAS28 ≥ 4.2) subgroups. Five-year trajectories of functionality (HAQ) were the primary outcome in comparing pRLDA versus pMDA and assessing heterogeneity within the pMDA subgroups through multivariable mixed-effect regression. We further compared serious adverse events (SAEs) occurrence between the two groups. RESULTS: We identified 295 patients with pMDA and 90 patients with pRLDA, the former group comprising of plMDA (n = 133, 45%) and phMDA (n = 162, 55%). pMDA was associated with worse 5-year functionality trajectory than pRLDA (+ 0.27 HAQ units, CI 95% + 0.22 to + 0.33; p < 0.0001), while the phMDA subgroup had worse 5-year functionality than plMDA (+ 0.26 HAQ units, CI 95% 0.18 to 0.36; p < 0.0001). Importantly, higher persistent disease activity was associated with more SAEs [pRLDA: 0.2 ± 0.48 vs pMDA: 0.5 ± 0.96, p = 0.006; plMDA: 0.32 ± 0.6 vs phMDA: 0.64 ± 1.16, p = 0.038]. Male gender (p = 0.017), lower baseline DAS28 (p < 0.001), HAQ improvement > 0.22 (p = 0.029), and lower average DAS28 during the first trimester since treatment initiation (p = 0.001) independently predicted grouping into pRLDA. CONCLUSIONS: In clinical practice, RA patients with pMDA while on bDMARDs have adverse long-term outcomes compared to lower disease activity status, while heterogeneity exists within the pMDA group in terms of 5-year functionality and SAEs. Targeted studies to better characterize pMDA subgroups are needed, in order to assist clinicians in tailoring treatments.

Sjögren's Syndrome: The Clinical Spectrum of Male Patients.

BACKGROUND: To compare the clinical, serological and histologic features between male and female patients with Sjögren's syndrome (SS) and explore the potential effect of gender on lymphoma development. METHODS: From a multicenter population (Universities of Udine, Pisa and Athens, Harokopion and Ioannina (UPAHI)) consisting of consecutive SS patients fulfilling the 2016 ACR/EULAR criteria, male patients were identified, matched and compared with female controls. Data-driven multivariable logistic regression analysis was applied to identify independent lymphoma-associated factors. RESULTS: From 1987 consecutive SS patients, 96 males and 192 matched female controls were identified and compared. Males had a higher frequency of lymphoma compared to females (18% vs. 5.2%, OR = 3.89, 95% CI: 1.66 to 8.67; p = 0.0014) and an increased prevalence of serum anti-La/SSB antibodies (50% vs. 34%, OR = 1.953, 95% CI: 1.19 to 3.25; p = 0.0128). No differences were observed in the frequencies of lymphoma predictors between the two genders. Data-driven multivariable logistic regression analysis revealed negative association of the female gender with lymphoma and positive association with lymphadenopathy. CONCLUSION: Male SS patients carry an increased risk of lymphoma development. Although statistics showed no difference in classical lymphoma predictors compared to females, data-driven analysis revealed gender and lymphadenopathy as independent lymphoma-associated features.

Anti-Ro52 and/or anti-Ro60 immune reactivity: autoantibody and disease associations.

OBJECTIVES: This study aims to characterise the clinical phenotype and autoantibody associations in an autoimmune population positive for anti-Ro52 and/or anti-Ro60 autoantibodies. METHODS: The sera of 508 individuals tested for autoantibody presence were found positive for anti-Ro52 and/or anti-Ro60. Medical records were available for 272 of them. Correlations of clinical, laboratory and other autoantibodies as well as disease phenotypes with the presence of anti-Ro52 and/or anti-Ro60 reactivity were examined. RESULTS: Combined serum anti-Ro52/anti-Ro60 reactivity was the most frequent one, mostly seen in Sjögren's syndrome (SS) and systemic lupus erythematosus (SLE) patients. In these patients this reactivity strongly associated with anti-La and/or anti-dsDNA autoantibodies. SS patients with combined anti-Ro52/anti-Ro60 and anti-La reactivity had clinical and/or laboratory risk factors for lymphoma development. Solo anti-Ro52 reactivity was primarily found in idiopathic inflammatory myopathies (IIM), primary biliary cholangitis (PBC), rheumatoid arthritis (RA) and SS patients. Solo anti-Ro52 also associated with anti-Jo1 and anti-M2 autoantibodies and with interstitial lung disease (ILD) in a context of IIM-related lung injury. ILD patients with combined anti-Ro52/anti-Ro-60 reactivity were diagnosed mostly as RA and/or SS. Solo anti-Ro60 reactivity strongly correlated with oral ulcers and co-existed with autoantibodies to Sm and nRNP/Sm. CONCLUSIONS: Testing for autoantibodies against both Ro peptides may guide diagnosis, classify clinical manifestations in disease entities and define prognosis in certain autoimmune disorders. A distinct weight could be given to the isolated anti-Ro specificities in the SS classification criteria.

Overcoming the Barriers That Obscure the Interlinking and Analysis of Clinical Data Through Harmonization and Incremental Learning.

Goal: To present a framework for data sharing, curation, harmonization and federated data analytics to solve open issues in healthcare, such as, the development of robust disease prediction models. Methods: Data curation is applied to remove data inconsistencies. Lexical and semantic matching methods are used to align the structure of the heterogeneous, curated cohort data along with incremental learning algorithms including class imbalance handling and hyperparameter optimization to enable the development of disease prediction models. Results: The applicability of the framework is demonstrated in a case study of primary Sjögren's Syndrome, yielding harmonized data with increased quality and more than 85% agreement, along with lymphoma prediction models with more than 80% sensitivity and specificity. Conclusions: The framework provides data quality, harmonization and analytics workflows that can enhance the statistical power of heterogeneous clinical data and enables the development of robust models for disease prediction.

Autoimmune epithelitis (Sjögren's syndrome); the impact of metabolic status of glandular epithelial cells on auto-immunogenicity.

It is well established that distinct cell metabolic alterations strongly contribute to the modulation of innate and adaptive immune responses. In the past decade the term immunometabolism has been introduced to describe the intracellular metabolic shifts of immune cells that lead to alterations of their functions. The pathogenesis of Sjögren's syndrome (SS), also referred to as autoimmune epithelitis, is not completely understood, but strong evidence supports the central role of the salivary glandular epithelial cells which are the target cells in the initiation of the autoimmune responses. Moreover, the altered epithelial functional phenotype, observed in the salivary gland lesion, may explain their disturbed secretory as well as immunoregulatory functions. From an immunometabolic perspective we have focused our studies on the endoplasmic reticulum (ER) of the salivary gland epithelial cells (SGEC) and the implication of its altered functions in the immunogenicity of these cells in SS. We showed that ER of SGEC in SS patients in situ is stressed and extensively dilated. Using salivary gland cell cultures, we studied in vitro the effect of ER stress on the metabolic behavior and viability of the cells. ER stress induced by thapsigargin increased spliced X-box binding protein-1 (XBP-1, transcription factor that increases the transcription of UPR target genes) levels in a time-dependent manner followed by autophagy and resulted to cell apoptosis. In apoptotic cells, we observed that the autoantigens Ro52 and La were redistributed in apoptotic blebs. During the induction of ER stress autophagy rescued the cells from apoptosis acting as a protective mechanism. We have also shown that adiponectin, a multifunctional hormone, is upregulated in the SGEC of SS patients acting in an autocrine or paracrine manner in the same cells. Adiponectin through activation of AMPK, the major sensor for cell energy demands, protected SGEC from apoptosis. Our results in combination with the work of others indicate that any effort of cell adaptation to ER stress may up regulate a proinflammatory milieu. This enhances the notion that metabolic alterations of the targeted epithelial cells in SS, independently of the cause, may induce an immunogenic phenotype. Therefore, SGEC have the potential to directly regulate susceptibility to and/or severity of autoimmune responses. Since adiponectin plays a vital role in the viability of SGEC through phosphorylation of AMPK, therapeutic interventions using PPAR agonists that upregulate adiponectin and concomitantly modify the energy metabolism, may be promising candidates for therapeutic intervention in SS.

Enhancing medical data quality through data curation: a case study in primary Sjögren's syndrome.

OBJECTIVES: To address the need for automatically assessing the quality of clinical data in terms of accuracy, relevance, conformity, and completeness, through the concise development and application of an automated method which is able to automatically detect problematic fields and match clinical terms under a specific domain. METHODS: The proposed methodology involves the automated construction of three diagnostic reports that summarise valuable information regarding the types and ranges of each term in the dataset, along with the detected outliers, inconsistencies, and missing values, followed by a set of clinically relevant terms based on a reference model which serves as a set of terms which describes the domain knowledge of a disease of interest. RESULTS: A case study was conducted using anonymised data from 250 patients who were diagnosed with primary Sjögren's syndrome (pSS), yielding reliable outcomes that were highlighted for clinical evaluation. Our method was able to successfully identify 28 features with detected outliers, and unknown data types, as well as, identify outliers, missing values, similar terms, and inconsistencies within the dataset. The data standardisation method was able to match 76 out of 85 (89.41%) pSS-related terms according to a standard pSS reference model which has been introduced by the clinicians. CONCLUSIONS: Our results confirm the clinical value of the data curation method towards the improvement of the dataset quality through the precise identification of outliers, missing values, inconsistencies, and similar terms, as well as, through the automated detection of pSS-related relevant terms towards data standardisation.

Medical data quality assessment: On the development of an automated framework for medical data curation.

Data quality assessment has gained attention in the recent years since more and more companies and medical centers are highlighting the importance of an automated framework to effectively manage the quality of their big data. Data cleaning, also known as data curation, lies in the heart of the data quality assessment and is a key aspect prior to the development of any data analytics services. In this work, we present the objectives, functionalities and methodological advances of an automated framework for data curation from a medical perspective. The steps towards the development of a system for data quality assessment are first described along with multidisciplinary data quality measures. A three-layer architecture which realizes these steps is then presented. Emphasis is given on the detection and tracking of inconsistencies, missing values, outliers, and similarities, as well as, on data standardization to finally enable data harmonization. A case study is conducted in order to demonstrate the applicability and reliability of the proposed framework on two well-established cohorts with clinical data related to the primary Sjögren's Syndrome (pSS). Our results confirm the validity of the proposed framework towards the automated and fast identification of outliers, inconsistencies, and highly-correlated and duplicated terms, as well as, the successful matching of more than 85% of the pSS-related medical terms in both cohorts, yielding more accurate, relevant, and consistent clinical data.