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Introduction: This was an ambispective cohort study evaluating the prognostic significance of lymphocytic foci and its lymphoid composition in minor salivary gland biopsy (MSGB) for short-term disease flare and severity in Sjögren's syndrome (SS). Methods: The inclusion criteria comprised individuals meeting the ACR/EULAR 2016 criteria who underwent MSGB with an infiltration of more than 50 lymphocytes and received clinical diagnosis between September 2017 and December 2018. Patients with inadequate biopsy samples were excluded. The number of lymphocytic foci and their lymphoid composition in MSGB were assessed using immunofluorescence staining. Major organ damage and improvements in the EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI) were measured. Statistical analyses, including Cox and linear regressions, were conducted. Results: A total of 78 patients with at least one lymphocytic focus were included in the study. The presence of higher T-cell counts in lymphocytic foci in MSGB was associated with severe disease flare, and a logarithmic transformation of Tcell count indicated increased risk (HR 1.96, 95% CI 0.91-4.21). Improvements in the ESSDAI were associated with higher total lymphocyte count and T- and Bcell numbers in the lymphoid composition of the lymphocytic foci. Seropositive patients exhibited higher T CD4+ cell numbers. Correlation analysis showed negative associations between age and lymphocytic foci and the T-cell count. Positive correlations were observed between antinuclear antibody (ANA) titers and total lymphocyte numbers. Discussion: Patients with a higher number of T cells in the lymphocytic infiltrates of lymphocytic foci may have a two-fold risk of severe disease flare. The number of B cells and T CD4+ cells in the lymphocytic infiltrates of lymphocytic foci showed a weak but positive relation with the ESSDAI improvement during followup. Age and seropositivity appeared to influence the lymphoid composition of the lymphocytic foci. [ABSTRACT FROM AUTHOR]

Tocilizumab is a first-line biologic disease-modifying anti-rheumatic drug (bDMARD) that inhibits the interleukin-6 (IL-6) pathway by antagonizing the IL-6 receptor (IL-6R). Tocilizumab is widely used to treat rheumatoid arthritis (RA), a prevalent autoimmune disease that can cause irreversible joint damage and disability. Although many bDMARDs have been developed for RA, there is a lack of validated biomarkers which could guide personalized medicine strategies. To evaluate whether single-nucleotide polymorphisms (SNPs) in the IL6R gene could predict tocilizumab toxicity in patients with RA, we conducted a retrospective cohort study of 88 patients treated with tocilizumab. Six SNPs previously described in the IL6R gene were genotyped (rs12083537, rs11265618, rs4329505, rs2228145, rs4537545, and rs4845625). Using parametric tests, we studied the association between the SNPs and hepatotoxicity, infection, hypersensitivity, gastrointestinal, hematological, and dyslipidemia adverse events (AEs). We found associations between dyslipidemia and rs4845625 and between hematological AEs and rs11265618 and rs4329505. No further associations were found for the remaining SNPs and other AEs. Our findings support the potential clinical value of SNPs in the IL6R gene as predictive biomarkers for toxicity to tocilizumab in patients with RA. [ABSTRACT FROM AUTHOR]

In this paper, a theoretical study of the three-phase transformer behavior in the presence of a sag is presented by considering that the fault clearing is produced simultaneously in all phases. Analytical expressions of the magnetic flux and the inrush current after voltage recovery are obtained, and the results presented in the literature are analytically justified. The influence of depth, duration, and the initial point-on-wave on the peak value of the inrush current are studied for all sag types. Simple expressions to obtain the value of the current peaks are presented. Index Terms--Inrush current, transformer model, voltage sag.

Traction systems are generally single-phase loads that can cause voltage unbalances which affect the electric system operation. It is usual to delta-connect reactances with these singlephase loads to reduce voltage unbalances. The set of reactances and single-phase loads is known as a Steinmetz circuit. A parallel resonance can be produced between the capacitive reactance of the Steinmetz circuit and the system inductive reactances, which can damage power quality. This paper locates the frequency of this parallel resonance analytically and studies the influence of capacitor loss with respect to its design value. Experimental measurements are also presented to validate the obtained analytical results. Index Terms--Frequency scan, harmonic analysis, power quality.

In this paper, neutral conductor current in three-phase networks with single-phase ac/dc uncontrolled converters is analyzed, and the influence of the unbalances on neutral conductor current is analytically studied. It is shown that supply-voltage unbalance slightly affects the root-mean-square value of the neutral conductor current and load unbalance can increase it. The obtained results are validated with laboratory measurements. Index Terms--AC/DC converters, harmonic distortion, neutral conductor current.

This paper shows that the single-cage model is not the right choice to represent squirrel-cage induction motors in dynamic studies. Therefore, the aggregate model of a group of motors must be based on their double-cage models. Four aggregation methods that use the double-cage model have been studied. Various tests have been performed on several groups with a different number of motors. The accuracy of the aggregation methods has been calculated at different points of the torque-speed and current-speed curves. The highest error is always produced near the maximum torque point. Index Terms--Aggregate motor, double-cage model, single-cage model, squirrel-cage induction motor.

Single-phase loads such as traction systems cause voltage asymmetries and damage power quality. Reactors suitably connected to single-phase loads are used to reduce this unbalance. The set formed by reactors and single-phase loads is more commonly known as Steinmetz circuit. In nonsinusoidal conditions, the resonance between the reactors of the Steinmetz circuit and the system reactances can worsen the harmonic disturbances. This paper studies the harmonic response of an electric power system in the presence of a Steinmetz circuit. The study allows the parallel resonance to be predicted. The obtained results are validated with experimental measurements. Index Terms--Frequency scan, harmonic analysis, power quality.