Lipoxygenase-derived oxylipins are enriched in anti-citrullinated protein antibody (ACPA)-positive individuals at risk for developing rheumatoid arthritis.

BACKGROUND: Rheumatoid arthritis (RA) is typically preceded by an extended preclinical period where circulating autoantibodies, particularly anti-citrullinated protein antibodies (ACPA), are detectable in the absence of clinical arthritis. Increased dietary intake of anti-inflammatory omega-3 (ω3) polyunsaturated fatty acids (PUFA) has been shown to be associated with a lower the risk of developing incident RA in large epidemiological studies. It is currently not known how changes in fatty acid (FA) metabolism may impact on the progression towards RA in at-risk individuals. To begin to address this question, we profiled serum FAs and oxylipins in an established cohort of at-risk ACPA-positive first-degree relatives (FDR) of RA patients (N = 31), some of whom developed RA (N = 4), and compared their profile to ACPA-negative FDR from the same population (N = 10). METHODS: Gas chromatography (GC) was used for FA quantitation. Oxylipins were extracted and quantified using high-performance liquid chromatography-tandem mass spectrometry (HPLC/MS/MS). RESULTS: Although we did not detect any meaningful differences in overall FA content between ACPA + and ACPA - FDR, the levels of oxylipins derived from FA metabolism demonstrated significant differences between the two groups, with the ACPA + group demonstrating enrichment in circulating arachidonic acid- and eicosapentaenoic acid-derived molecules. Compared with the ACPA - FDR group, the ACPA + FDR, including those who progressed into inflammatory arthritis, displayed higher levels of LOX-derived oxylipins. CONCLUSION: ACPA seropositivity in otherwise unaffected individuals at-risk for developing future RA based on family history (FDR) is associated with alterations in the serum oxylipin profile that suggests dysregulated LOX activity.

Predictive Modeling of Tensile Strength in Aluminum Alloys via Machine Learning.

Aluminum alloys are widely used due to their exceptional properties, but the systematic relationship between their grain size and their tensile strength has not been thoroughly explored in the literature. This study aims to fill this gap by compiling a comprehensive dataset and utilizing machine learning models that consider both the alloy composition and the grain size. A pivotal enhancement to this study was the integration of hardness as a feature variable, providing a more robust predictor of the tensile strength. The refined models demonstrated a marked improvement in predictive performance, with XGBoost exhibiting an R2 value of 0.914. Polynomial regression was also applied to derive a mathematical relationship between the tensile strength, alloy composition, and grain size, contributing to a more profound comprehension of these interdependencies. The improved methodology and analytical techniques, validated by the models' enhanced accuracy, are not only relevant to aluminum alloys, but also hold promise for application to other material systems, potentially revolutionizing the prediction of material properties.

Brain Functional Network Generation Using Distribution-Regularized Adversarial Graph Autoencoder with Transformer for Dementia Diagnosis.

The topological connectivity information derived from the brain functional network can bring new insights for diagnosing and analyzing dementia disorders. The brain functional network is suitable to bridge the correlation between abnormal connectivities and dementia disorders. However, it is challenging to access considerable amounts of brain functional network data, which hinders the widespread application of data-driven models in dementia diagnosis. In this study, a novel distribution-regularized adversarial graph auto-Encoder (DAGAE) with transformer is proposed to generate new fake brain functional networks to augment the brain functional network dataset, improving the dementia diagnosis accuracy of data-driven models. Specifically, the label distribution is estimated to regularize the latent space learned by the graph encoder, which can make the learning process stable and the learned representation robust. Also, the transformer generator is devised to map the node representations into node-to-node connections by exploring the long-term dependence of highly-correlated distant brain regions. The typical topological properties and discriminative features can be preserved entirely. Furthermore, the generated brain functional networks improve the prediction performance using different classifiers, which can be applied to analyze other cognitive diseases. Attempts on the Alzheimer's Disease Neuroimaging Initiative (ADNI) dataset demonstrate that the proposed model can generate good brain functional networks. The classification results show adding generated data can achieve the best accuracy value of 85.33%, sensitivity value of 84.00%, specificity value of 86.67%. The proposed model also achieves superior performance compared with other related augmented models. Overall, the proposed model effectively improves cognitive disease diagnosis by generating diverse brain functional networks.

Serum proteomic networks associate with pre-clinical rheumatoid arthritis autoantibodies and longitudinal outcomes.

Objectives: The development of autoantibody directed towards citrullinated proteins (ACPA) are predictive of RA in at-risk individuals. The biological events that underpin loss of immune tolerance and progression into inflammatory arthritis are not known. We sought to identify serum proteomic alterations that drive autoantibody formation, persistence and progression into inflammatory arthritis in a cohort of first-degree relatives (FDR) of RA patients. Methods: We studied baseline serum samples from a cohort of Indigenous FDR (n = 147) and quantified serum proteins using a 48-plex platform. Longitudinal outcomes were defined on the basis of ACPA status and progression into inflammatory arthritis (IA). K-means clustering, differential expression, and principal components analyze group differences. A co-expression module analysis was used to identify enriched networks. Random forest was used to classify ACPA positive samples, while network analysis was used to understand underlying biological processes based on protein expression. Results: We defined 6 proteomic clusters, with enrichment of ACPA positive samples in one of the clusters. 23 of 24 differentially expressed proteins in ACPA positive samples were upregulated. A co-expression network was enriched in ACPA positive sera and individuals who progressed into IA. Random Forest achieved an area under the curve of 0.767 to classify ACPA positive sera in a test dataset. Network analysis revealed upregulation of JAK-STAT signalling as being activated in those at highest risk to develop future IA. Conclusions: The serum proteome provides a rich dataset to understand biological processes in ACPA seropositive individuals. A combination of serum biomarkers, including ACPA, may predict future arthritis onset in at-risk individuals.

Increased frequency of TIGIT+ CD4 T Cell subset in autoantibody-positive first-degree relatives of patients with rheumatoid arthritis.

Background: Despite immune cell dysregulation being an important event preceding the onset of rheumatoid arthritis (RA), the phenotype of T and B cells in preclinical RA is less understood. The aim of this study was to characterize T and B cell populations in RA patients and their autoantibody (aAb) negative and positive first-degree relatives (FDR). Methods: Cryopreserved peripheral blood mononuclear cells (PBMCs) collected at scheduled visits from aAb-(n=25), and aAb+ FDR (n=10) and RA patients (n=13) were thawed and stained using optimized antibody cocktails as per a specific 13-color T or B cell panel. Immunophenotyping was performed using a Cytoflex LX (Beckman-Coulter) flow cytometer and FlowJo software was used for analyzing the frequency of immune cell populations. Results: Multicolor flow cytometry experiments identified an increased TIGIT expression in circulating lymphocytes of aAb+ FDR and RA patients, relative to aAb- FDR (P<0.01). These TIGIT+ T cells exhibited a memory phenotype and expressed high levels of PD-1, ICOS, HLA-DR, CXCR3 and CXCR5. Moreover, increased TIGIT+ CD4 T cell frequency correlated with the frequency of PD-1+ CD4 T cells (r = 0.4705: P = 0.0043) and circulating levels of ACPA and RF. We also identified a decreased frequency of CD27+IgD- switched memory B cells in RA patients (P < 0.01), while increased frequency of TIGIT+ CD4 T cells in FDR correlated with the frequency of PD1+PTEN+ B cells (r = 0.6838, P = 0.0004) and autoantibody positivity (P = 0.01). Conclusion: We demonstrate TIGIT as a distinct CD4 T cell marker for differentiating aAb- FDR from aAb+FDR and might play a critical role in regulating T and B cell crosstalk in preclinical RA.

Characteristics of Small-Molecule Migration of Silicone Rubber Insulator in Electrical Power Systems.

The migration of low-molecular-weight components of polysiloxane (small molecules) to the surface of high-temperature-vulcanizing silicone rubber (HTV-SR) ensures its hydrophobicity and tends to coat the surface of pollutants, which would otherwise lower hydrophobicity. The transferability of hydrophobicity will ensure the insulator maintains its higher hydrophobicity after being coated with surface pollutants, thus providing the insulator with higher pollution flashover voltage. This migration process takes a certain time, and in this paper, the time characteristics of hydrophobicity transfer from HTV-SR coated with ten different inert materials were investigated. Ten different inert materials have different migration times and static contact angles, possibly due to the influence of pollution material characteristics on the characteristics of small-molecule migration. Thermogravimetric analysis (TG), Fourier transform infrared spectroscopy (FTIR), and gas chromatography-mass spectrometry (GC-MS) were used to analyze the migration of small molecules to the polluted surface. The evidence of small molecules migrating to the surface of the polluted material over time was found. Furthermore, the influence of pollution material characteristics on small-molecule migration was analyzed via SEM, specific surface area, and porosity. On that basis, the hydrophobicity migration characteristics of mixtures of kaolin and kieselguhr were also studied and compared to determine how best to simulate the behavior of natural pollution using artificial pollutants and their mixtures.

Streamer Propagation along the Insulator with the Different Curved Profiles of the Shed.

The flashover along the insulator endangers the reliable operation of the electrical power system. The reasonable curved profiles of the shed could improve the flashover voltage, which would reduce power system outages. The research on the influence of the curved profiles of the shed on the streamer propagation along the insulator made of polymer was presented in the paper. The streamer propagation "stability" field, path, and velocity affected by the curved profiles of the shed, were measured by ultraviolet camera, ICCD camera, and photomultipliers. The "surface" component of the streamer is stopped at the shed with the different curved profiles, while the "air" component could go round the shed and reach the cathode. The streamer propagation "stability" fields are inversely proportional to the curved profiles of the shed. The streamer propagation velocities are proportional to the curved profiles of the shed. The relationship between the streamer propagation and the flashover propagation was discussed in depth. The subsequent flashover propagation is greatly affected by the streamer propagation path and "stability" field. Furthermore, the influence of the material properties on the streamer propagation path was also discussed in depth.

Functional Disability to Evaluate the Risk of Arthritis in First-degree Relatives of Patients With Rheumatoid Arthritis.

OBJECTIVE: The events that occur prior to the onset of rheumatoid arthritis (RA) continue to be delineated. We examined the relationship between self-reported joint symptoms, functional disability, and anticitrullinated protein antibody (ACPA) status in a cohort of first-degree relatives (FDR) of patients with RA who are at risk of future disease development. METHODS: We studied a cohort of 279 FDR of First Nations (FN) patients with RA who are at increased risk for future RA development, and analyzed data collected at their enrollment study visit. In parallel, we analyzed data from 279 FN subjects with no family history of RA. A subset of FDR developed inflammatory arthritis and we analyzed longitudinal data in this group. RESULTS: The prevalence of joint symptoms and functional disability was higher in FDR compared to non-FDR (all P < 0.001). Difficulty walking (37.3% vs 18.0%) and modified Health Assessment Questionnaire (HAQ) results were higher in ACPA-positive FDR compared to ACPA-negative FDR, and HAQ was independently associated with ACPA seropositivity (OR 2.79, 95% CI 1.56-5.00). Longitudinally, in individuals who developed ACPA-positive RA, ACPA level and HAQ score were significantly associated (R = 0.45, P < 0.001) in the preclinical period. CONCLUSION: Compared to population-based controls, FDR have a high burden of joint symptoms and functional disability. Functional disability was most closely associated with ACPA seropositivity in the FDR, suggesting a direct role for ACPA outside of the context of clinically detectable synovitis. HAQ appears to be particularly valuable in the assessment of individuals at risk for future RA development.

Influence of Silicone Rubber Coating on the Characteristics of Surface Streamer Discharge.

A pollution flashover along an insulation surface-a catastrophic accident in electrical power system-threatens the safe and reliable operation of a power grid. Silicone rubber coatings are applied to the surfaces of other insulation materials in order to improve the pollution flashover voltage of the insulation structure. It is generally believed that the hydrophobicity of the silicone rubber coating is key to blocking the physical process of pollution flashover, which prevents the formation of continuously wet pollution areas. However, it is unclear whether silicone rubber coating can suppress the generation of pre-discharges such as corona discharge and streamer discharge. In this research, the influence of silicone rubber coating on the characteristics of surface streamer discharge was researched in-depth. The streamer 'stability' propagation fields of the polymer are lower than that of the polymer with silicone rubber coating. The velocities of the streamer propagation along the polymer are higher than those along the polymer with silicone rubber coating. This indicates that the surface properties of the polymer with the silicone rubber coating are less favorable for streamer propagation than those of the polymer.

Associação da hipertensão com a gravidade e a mortalidade de pacientes hospitalizados com COVID-19 em Wuhan, China: Estudo unicêntrico e retrospectivo / Association of hypertension with severity and mortality in hospitalized patients with COVID-19 in wuhan, China: A single-centered, retrospective study

Resumo Fundamento A doença Coronavírus 2019 (COVID-19), causada pela síndrome respiratória aguda grave Coronavírus 2 (SARS-CoV-2), espalhou-se pelo mundo. Objetivo Investigar a associação entre a hipertensão e a gravidade/mortalidade de pacientes hospitalizados com COVID-19 em Wuhan, China. Métodos Um total de 337 pacientes diagnosticados com COVID-19 no Sétimo Hospital da cidade de Wuhan, de 20 de janeiro a 25 de fevereiro de 2020, foram inseridos e analisados em um estudo de caso unicêntrico e retrospectivo. O nível de significância adotado para a análise estatística foi 0,05. Resultados Dos 337 pacientes com diagnóstico confirmado de COVID-19, 297 (87.8%) tiveram alta do hospital e 40 pacientes (22,9%) morreram. A idade média foi de 58 anos (variando de 18 a 91 anos). Havia 112 (33,2%) pacientes diagnosticados com hipertensão no momento da internação (idade média, 65,0 anos [variação, 38-91 anos]; sendo 67 homens [59,8%, IC95%: 50,6%-69,0%], p=0,0209). Pacientes com hipertensão apresentaram uma porção significativamente maior de casos graves (69 [61,6%, IC95%: 52,5%-70,8%] vs. 117 [52,0%, IC95%: 45,4%-58,6%] em pacientes graves e 23 [19,3%, IC95%: 12,9%-28,1%] vs. 27 [12,0%, IC95%: 7,7%-16,3%] em pacientes críticos, p=0,0014) e maiores taxas de mortalidade (20 [17,9%, IC95%: 10,7%-25,1%] vs. 20 [8,9%, IC95%: 5,1%-12,6%, p=0,0202). Além disso, pacientes hipertensos apresentaram níveis anormais de vários indicadores, como linfopenia e inflamação, e nas funções cardíacas, hepáticas, renais e pulmonares no momento da internação. O grupo de pacientes com hipertensão também demonstrou níveis maiores de TNT e creatinina próximo da alta. Conclusão A hipertensão está altamente associada à gravidade ou mortalidade da COVID-19. Um tratamento agressivo deve ser considerado para pacientes hipertensos com COVID-19, principalmente com relação a lesões cardíacas e dos rins.

Abstract Background Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread worldwide. Objective To investigate the association between hypertension and severity/mortality in hospitalized patients with COVID-19 in Wuhan, China. Methods A total of 337 patients diagnosed with COVID-19 at the Seventh Hospital of Wuhan City, from January 20 to February 25, 2020, were enrolled and analyzed in a retrospective, single-center case study. The significance level adopted in the statistical analysis was 0.05. Results Of the 337 patients with confirmed diagnosis of COVID-19, 297 (87.8%) were discharged from the hospital and 40 patients (22.9%) died. The median age was 58 years (range, 18-91 years). There were 112 (33.2%) patients diagnosed with hypertension at admission (median age, 65.0 years [range, 38-91 years]; 67 [59.8%, 95%CI: 50.6%-69.0%] men, p=0.0209). Patients with hypertension presented a significantly higher portion of severe cases (69 [61.6%, 95%CI:52.5%-70.8%] vs. 117 [52.0%, 95%CI: 45.4%-58.6%] in severe patients and 23 [19.3%, 95%CI:12.9%-28.1%] vs. 27 [12.0%, 95%CI: 7.7%-16.3%] in critical patients, p=0.0014) and higher mortality rates (20 [17.9%, 95%CI: 10.7%-25.1%] vs. 20 [8.9%, 95%CI: 5.1%-12.6%, p=0.0202). Moreover, hypertensive patients presented abnormal levels of multiple indicators, such as lymphopenia, inflammation, heart, liver, kidney, and lung function at admission. The hypertension group still displayed higher levels of TnT and creatinine at approaching discharge. Conclusion Hypertension is strongly associated with severity or mortality of COVID-19. Aggressive treatment may be considered for COVID-19 patients with hypertension, especially regarding cardiac and kidney injury.

Association of Hypertension with Severity and Mortality in Hospitalized Patients with COVID-19 in Wuhan, China: A Single-centered, Retrospective Study. / Associação da Hipertensão com a Gravidade e a Mortalidade de Pacientes Hospitalizados com COVID-19 em Wuhan, China: Estudo Unicêntrico e Retrospectivo.

BACKGROUND: Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread worldwide. OBJECTIVE: To investigate the association between hypertension and severity/mortality in hospitalized patients with COVID-19 in Wuhan, China. METHODS: A total of 337 patients diagnosed with COVID-19 at the Seventh Hospital of Wuhan City, from January 20 to February 25, 2020, were enrolled and analyzed in a retrospective, single-center case study. The significance level adopted in the statistical analysis was 0.05. RESULTS: Of the 337 patients with confirmed diagnosis of COVID-19, 297 (87.8%) were discharged from the hospital and 40 patients (22.9%) died. The median age was 58 years (range, 18-91 years). There were 112 (33.2%) patients diagnosed with hypertension at admission (median age, 65.0 years [range, 38-91 years]; 67 [59.8%, 95%CI: 50.6%-69.0%] men, p=0.0209). Patients with hypertension presented a significantly higher portion of severe cases (69 [61.6%, 95%CI:52.5%-70.8%] vs. 117 [52.0%, 95%CI: 45.4%-58.6%] in severe patients and 23 [19.3%, 95%CI:12.9%-28.1%] vs. 27 [12.0%, 95%CI: 7.7%-16.3%] in critical patients, p=0.0014) and higher mortality rates (20 [17.9%, 95%CI: 10.7%-25.1%] vs. 20 [8.9%, 95%CI: 5.1%-12.6%, p=0.0202). Moreover, hypertensive patients presented abnormal levels of multiple indicators, such as lymphopenia, inflammation, heart, liver, kidney, and lung function at admission. The hypertension group still displayed higher levels of TnT and creatinine at approaching discharge. CONCLUSION: Hypertension is strongly associated with severity or mortality of COVID-19. Aggressive treatment may be considered for COVID-19 patients with hypertension, especially regarding cardiac and kidney injury.

FUNDAMENTO: A doença Coronavírus 2019 (COVID-19), causada pela síndrome respiratória aguda grave Coronavírus 2 (SARS-CoV-2), espalhou-se pelo mundo. OBJETIVO: Investigar a associação entre a hipertensão e a gravidade/mortalidade de pacientes hospitalizados com COVID-19 em Wuhan, China. MÉTODOS: Um total de 337 pacientes diagnosticados com COVID-19 no Sétimo Hospital da cidade de Wuhan, de 20 de janeiro a 25 de fevereiro de 2020, foram inseridos e analisados em um estudo de caso unicêntrico e retrospectivo. O nível de significância adotado para a análise estatística foi 0,05. RESULTADOS: Dos 337 pacientes com diagnóstico confirmado de COVID-19, 297 (87.8%) tiveram alta do hospital e 40 pacientes (22,9%) morreram. A idade média foi de 58 anos (variando de 18 a 91 anos). Havia 112 (33,2%) pacientes diagnosticados com hipertensão no momento da internação (idade média, 65,0 anos [variação, 38-91 anos]; sendo 67 homens [59,8%, IC95%: 50,6%-69,0%], p=0,0209). Pacientes com hipertensão apresentaram uma porção significativamente maior de casos graves (69 [61,6%, IC95%: 52,5%-70,8%] vs. 117 [52,0%, IC95%: 45,4%-58,6%] em pacientes graves e 23 [19,3%, IC95%: 12,9%-28,1%] vs. 27 [12,0%, IC95%: 7,7%-16,3%] em pacientes críticos, p=0,0014) e maiores taxas de mortalidade (20 [17,9%, IC95%: 10,7%-25,1%] vs. 20 [8,9%, IC95%: 5,1%-12,6%, p=0,0202). Além disso, pacientes hipertensos apresentaram níveis anormais de vários indicadores, como linfopenia e inflamação, e nas funções cardíacas, hepáticas, renais e pulmonares no momento da internação. O grupo de pacientes com hipertensão também demonstrou níveis maiores de TNT e creatinina próximo da alta. CONCLUSÃO: A hipertensão está altamente associada à gravidade ou mortalidade da COVID-19. Um tratamento agressivo deve ser considerado para pacientes hipertensos com COVID-19, principalmente com relação a lesões cardíacas e dos rins.

Association of diabetes with severity and mortality in hospitalized patients with COVID-19 in Wuhan, China: a single-centered, retrospective study.

OBJECTIVE: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread worldwide. The aim this study was to investigate the association of diabetes with severity and mortality among hospitalized patients with COVID-19 in Wuhan, China. METHODS: This retrospective, single-center case study enrolled a total of 564 patients diagnosed with COVID-19 at the Seventh Hospital of Wuhan City, between January 20 and March 15, 2020. RESULTS: Among the 564 patients with confirmed COVID-19, 509 (85.1%) were discharged and 55 (9.8%) died. The median age was 59 years (range, 10-93 years). A total of 85 (15.1%) patients were diagnosed with diabetes on admission (median age, 65.0 [range, 34-91] years). Patients with diabetes had significantly higher proportions of critical cases (24 [28.2%] vs. 66 [13.8%]) and in-hospital mortality (17 [20%] vs. 38 [7.9%]). Moreover, patients with diabetes presented abnormal levels of multiple indicators concerning lymphopenia, inflammation, heart, liver, kidney, and lung function on admission, while diabetic patient group still display higher troponin T (TnT) levels when approaching discharge. The Kaplan-Meier survival curve indicated a trend toward poorer survival in diabetic patients compared to non-diabetic patients, also evidenced by abnormal laboratory biomarker changes regarding multiple system impairments among COVID-19 patients with diabetes with in-hospital death. CONCLUSION: The detailed clinical investigation of 564 hospitalized patients with COVID-19 indicated a considerable association between diabetes and COVID-19 severity or mortality. Thus, more intensive treatment may be considered for COVID-19 patients with diabetes, especially regarding to cardiac injury.

Expansion of Alternative Autoantibodies Does Not Follow the Evolution of Anti-Citrullinated Protein Antibodies in Preclinical Rheumatoid Arthritis: An Analysis in At-Risk First Degree Relatives.

OBJECTIVE: Co-occurrence of autoantibodies specific for ≥1 autoimmune disease is widely prevalent in rheumatoid arthritis (RA) patients. To understand the prevalence of polyautoimmunity in preclinical RA, we performed a comprehensive autoantibody assessment in a First Nations cohort of at-risk first-degree relatives (FDR) of RA patients, a subset of whom subsequently developed RA (progressors). METHODS: Venous blood was collected from all study participants (n = 50 RA patients and 64 FDR) at scheduled visits, and serum was stored at -20°C. High-sensitivity C-reactive protein level, anti-citrullinated protein antibody (ACPA) status, and autoantibody status were determined using commercially available enzyme-linked immunosorbent assay kits. Rheumatoid factor (RF) was detected by nephelometry. Antinuclear autoantibodies (ANA) were identified using Hep-2 indirect immunofluorescence assay (IFA) and classified according to international consensus nomenclature as various anti-cell (AC) patterns. RESULTS: Of our study cohort, 78.9% had positive ANA reactivity (≥1:80), which was either a homogenous, fine-speckled (AC-1 and AC-4) or mixed IFA pattern. Importantly, the AC-4 and mixed ANA patterns were also observed in progressors at the time of disease onset. While all of the RA patients showed a high prevalence of arthritis-associated autoantibodies, they also had a high prevalence of extractable nuclear antigen-positive autoantibodies to other autoantigens. In FDR, we did not observe any increase in serum autoreactivity to nonarthritis autoantigens, either cross-sectionally or in samples collected longitudinally from progressors prior to RA onset. CONCLUSION: While alternative autoimmunity and ANA positivity are widely prevalent in First Nations populations, including asymptomatic, seronegative FDR, expansion of alternative autoimmunity does not occur in parallel with ACPA expansion in FDR and is restricted to patients with established RA.

Association of a Serum Protein Signature With Rheumatoid Arthritis Development.

OBJECTIVE: The pathophysiologic events that precede the onset of rheumatoid arthritis (RA) remain incompletely understood. This study was undertaken to identify changes in the serum proteome that precede the onset of RA, with the aim of providing new insights into the pathogenic mechanisms that lead to its development. METHODS: In a cohort of first-degree relatives of Indigenous North American RA patients, the SomaScan proteomics platform was used to determine the levels of 1,307 proteins in multiple longitudinal serum samples from 17 individuals who were followed up prospectively to the time of disease onset. Proteomic signatures from this group of individuals (designated the progressor group) were compared to those in a group of individuals who were considered at risk of developing RA, stratified as either positive (n = 63) or negative (n = 47) for anti-citrullinated protein antibodies (ACPAs) (designated the at-risk group). Machine learning was used to identify a protein signature that could accurately classify those individuals at highest risk of future RA development. RESULTS: A preclinical proteomic signature that differentiated RA progressors from at-risk individuals, irrespective of ACPA status, was identified (area under the curve 0.913, accuracy 91.2%). Importantly, the predictive preclinical proteomic signature was present not only in serum samples obtained close to the onset of RA, but also in serum samples obtained a median of 30.9 months prior to onset. Network analysis implicated the activation of Toll-like receptor 2 and production of tumor necrosis factor and interleukin-1 as key events that precede RA progression. CONCLUSION: Alterations in the serum proteome in the preclinical phase of RA can emerge years prior to the onset of disease. Our findings suggest that the serum proteome provides a rich source of proteins serving both to classify at-risk individuals and to identify molecular pathways involved in the development of clinically detectable RA.

Association of diabetes with severity and mortality in hospitalized patients with COVID-19 in Wuhan, China: a single-centered, retrospective study

ABSTRACT Objective: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread worldwide. The aim this study was to investigate the association of diabetes with severity and mortality among hospitalized patients with COVID-19 in Wuhan, China. Subjects and methods: This retrospective, single-center case study enrolled a total of 564 patients diagnosed with COVID-19 at the Seventh Hospital of Wuhan City, between January 20 and March 15, 2020. Results: Among the 564 patients with confirmed COVID-19, 509 (85.1%) were discharged and 55 (9.8%) died. The median age was 59 years (range, 10-93 years). A total of 85 (15.1%) patients were diagnosed with diabetes on admission (median age, 65.0 [range, 34-91] years). Patients with diabetes had significantly higher proportions of critical cases (24 [28.2%] vs. 66 [13.8%]) and in-hospital mortality (17 [20%] vs. 38 [7.9%]). Moreover, patients with diabetes presented abnormal levels of multiple indicators concerning lymphopenia, inflammation, heart, liver, kidney, and lung function on admission, while diabetic patient group still display higher troponin T (TnT) levels when approaching discharge. The Kaplan-Meier survival curve indicated a trend toward poorer survival in diabetic patients compared to non-diabetic patients, also evidenced by abnormal laboratory biomarker changes regarding multiple system impairments among COVID-19 patients with diabetes with in-hospital death. Conclusion: The detailed clinical investigation of 564 hospitalized patients with COVID-19 indicated a considerable association between diabetes and COVID-19 severity or mortality. Thus, more intensive treatment may be considered for COVID-19 patients with diabetes, especially regarding to cardiac injury.

Circulating levels of free 25(OH)D increase at the onset of rheumatoid arthritis.

OBJECTIVE: Epidemiological studies suggest vitamin D deficiency as a potential risk factor for rheumatoid arthritis (RA) development, a chronic autoimmune disorder highly prevalent in indigenous North American (INA) population. We therefore profiled the circulating levels of 25-hydroxyvitaminD [25(OH)D], an active metabolite of vitamin D, in a cohort of at-risk first-degree relatives (FDR) of INA RA patients, a subset of whom subsequently developed RA (progressors). METHODS: 2007 onward, serum samples from INA RA patients and FDR were collected at the time of a structured baseline visit and stored at -20°C. Anti-citrullinated protein antibodies (ACPA), 25(OH)D, hs-CRP, vitamin-D binding protein (VDBP) and parathyroid hormone (PTH) levels were determined using ELISA and rheumatoid factor (RF) seropositivity was determined by nephelometry. RESULTS: We demonstrate that 25 (OH) D concentrations were lower in winter than summer (P = 0.0538), and that serum 25(OH)D levels were higher in samples collected and stored after 2013 (P<0.0001). Analysis of samples obtained after 2013 demonstrated that 37.6% of study participants were 25(OH)D insufficient (<75nmol/L). Also, seropositive RA patients and FDR had lower 25(OH)D levels compared to ACPA-/FDR (P<0.05, P<0.01 respectively). Linear regression analysis showed 25(OH)D insufficiency was inversely associated with presence of RA autoantibodies. Longitudinal samples from 14 progressors demonstrated a consistent increase in 25(OH)D levels at the time they exhibited clinically detectable joint inflammation, without any significant change in VDBP or PTH levels. Spearman rank correlation analysis showed significant association between 25(OH)D and PTH levels, both in RA patients and progressors at RA onset time. CONCLUSION: We demonstrate that 25(OH)D levels in serum increased at RA onset in progressors. The potential role that vitamin D metabolites and their downstream effects play in RA transition requires further investigation.

Effect of multi-pollutant state of ozone and sulfur dioxide on atmospheric corrosivity map of Guangdong Province.

Guangdong Province, which is located in southern China, has a tropical climate with high temperatures and humidity, making it extremely unfavourable for the corrosion resistance of various materials. Meanwhile, as a quickly developing region in China, Guangdong Province is also facing multi-pollutant conditions, which seriously affect the atmospheric degradation of the materials in this region. It is therefore necessary to identify the key air pollutants that affect the atmospheric corrosivity of Guangdong Province and to propose targets of air pollutant control. An analysis of the environmental data and corrosion rates in Guangdong Province showed that the atmospheric corrosivity of the entire region is closely related to the presence of sulfur dioxide (SO2) and ozone (O3). In addition, a superposition model was utilised to reflect the synergistic effect of SO2 and O3, and a superimposed map of both pollutants was drawn to demonstrate their amount. To control the corrosion rate of carbon steel and avoid exceeding the C2 classification in ISO 9223, the following targets of air pollutant control are proposed: an SO2 concentration of lower than 10 µg m-3 and an O3 level of lower than 85 µg m-3.

Human host defence peptide LL37 and anti-cyclic citrullinated peptide antibody in early inflammatory arthritis.

Objective: Antibodies to citrullinated peptides (anti-CCP) develop in individuals predisposed to rheumatoid arthritis (RA). Neutrophil extracellular traps are a major source of citrullinated antigens and the immunomodulatory host defence peptide LL-37. Vitamin D regulates LL-37 expression. This study assessed the associations of LL-37 and anti-CCP, vitamin D metabolites and vitamin D receptor (VDR) polymorphisms in early inflammatory arthritis (EIA). Methods: Serum LL-37, 25-hydroxy-vitamin D (25OHvitD) and anti-CCP were measured by ELISA in treatment naïve EIA (n = 181). VDR single nucleotide polymorphisms (Fok1, Bsm1, Apa1, Taq1, Cdx-2) and HLADRB1 shared epitope (SE) alleles were detected by DNA amplification. Associations were tested in multivariable models. Median (25%, 75%) or percentiles are reported. Results: Participants (70 % female, age 56 [45, 66] years, disease activity score [DAS28ESR3var] 3.7 [2.8, 4.8], 41 % anti-CCP positive, 68 % RA) had low serum 25OHvitD; 20.5 nmol/L (13.9, 29.0). In multivariable models, controlling for age, sex, SE, smoking and vitamin D deficiency, LL37 level (top quartile) associated with anti-CCP seropositivity (OR 22; 95% CI 4 to 104). Conclusions: Levels of circulating LL-37 are associated with anti-CCP seropositivity. LL37 activity may be one mechanism linking infection and toxin exposure to anti-CCP generation.

N-Linked Glycans in the Variable Domain of IgG Anti-Citrullinated Protein Antibodies Predict the Development of Rheumatoid Arthritis.

OBJECTIVE: Anti-citrullinated protein antibodies (ACPAs) are disease-specific biomarkers in rheumatoid arthritis (RA). More than 90% of IgG ACPAs harbor N-linked glycans in the antibody variable (V) domain. The corresponding N-glycosylation sites in ACPA V-region sequences result from somatic hypermutation, a T cell-dependent process. As ample evidence indicates that T cells drive the maturation of the ACPA response prior to arthritis onset, we undertook this study to investigate whether the presence of glycans in IgG ACPA V domains predicts the transition from predisease autoimmunity to overt RA. METHODS: We analyzed 2 independent sets of serum samples obtained from 126 ACPA-positive first-degree relatives (FDRs) of RA patients. Both sets originated from an Indigenous North American population and comprised cross-sectional and longitudinal samples of individuals who did or did not develop inflammatory arthritis. Serum IgG ACPAs were affinity-purified and subjected to ultra high-performance liquid chromatography-based glycan analysis. RESULTS: In both data sets, FDR-derived IgG ACPA displayed markedly lower levels of V domain glycans (<50%) compared to IgG ACPA from RA patients. Notably, FDRs who later developed RA showed extensive V-domain glycosylation before the onset of arthritis. Moreover, IgG ACPA V-domain glycosylation was strongly associated with future development of RA (hazard ratio 6.07 [95% confidence interval 1.46-25.2]; P = 0.013). CONCLUSION: Extensive glycosylation of the IgG ACPA V domain is present in a subset of predisposed FDRs of Indigenous North American RA patients. The presence of this feature substantially increases the risk of RA development. Based on these findings, we propose that glycosylation of the IgG ACPA V domain represents a predictive marker for RA development in ACPA-positive individuals and may serve to better target prevention measures.

A Prospective Study of the Development of Inflammatory Arthritis in the Family Members of Indigenous North American People With Rheumatoid Arthritis.

OBJECTIVE: To determine the incidence of inflammatory arthritis and autoantibody prevalence in Indigenous North American people. METHODS: Unaffected relatives of Indigenous North Americans with rheumatoid arthritis (RA) from central Canada and Alaska were systematically monitored from 2005 to 2017. Rheumatoid factor (RF) and anti-citrullinated protein antibodies (ACPAs) were tested at every visit, and a subset was tested for ACPA fine specificity using a custom multiplex assay. Multistate models based on all available study visits were developed to determine the likelihood of transitioning between autoantibody states, or to inflammatory arthritis. RESULTS: Eighteen of 374 relatives (4.8%) developed inflammatory arthritis during follow-up (after a mean ± SD of 4.7 ± 2.4 years), yielding a transition rate of 9.2 cases/1,000 person-years. Thirty percent of those who developed inflammatory arthritis were seronegative at baseline, but all were seropositive at inflammatory arthritis onset. Although 30% of ACPA/RF double-seropositive individuals developed inflammatory arthritis (after 3.2 ± 2.2 years), the majority of these individuals did not develop inflammatory arthritis. Multistate modeling indicated a 71% and 68% likelihood of ACPA and RF seropositive states, respectively, reverting to a seronegative state after 5 years, and a 39% likelihood of an ACPA/RF double-seropositive state becoming seronegative. Fine specificity testing demonstrated an expansion of the ACPA repertoire prior to the development of inflammatory arthritis. CONCLUSION: Despite a high incidence of inflammatory arthritis in this cohort of at-risk relatives of Indigenous North Americans with RA, a large proportion of autoantibody-positive individuals do not develop inflammatory arthritis and revert back to an autoantibody-negative state.