Increased serum interleukin-41 correlates with disease severity in myasthenia gravis.

BACKGROUND: Myasthenia gravis (MG) is an autoimmune disease mediated by pathogenic antibodies produced by abnormally activated B cells, resulting in neuromuscular junction transmission dysfunction. Interleukin-41 (IL-41) is a novel immunomodulatory cytokine that has been implicated in various metabolic, inflammatory, and autoimmune diseases. The role of IL-41 in MG is still unclear up to now, our study aimed to investigate the level of IL-41 in MG patients and its correlation with clinical features and inflammatory indicators. METHODS: Totally, 60 MG patients and 30 healthy controls (HC) were recruited. Baseline data and laboratory parameters were routinely recorded through electronic medical systems. IL-41 levels were measured by enzyme-linked immunosorbent assay. Proportions of T-cell and B-cell subsets and natural killer cells were analyzed by flow cytometry. The correlation between serum IL-41 and MG related parameters was investigated, and the clinical value of IL-41 in the diagnosis of MG was evaluated by receiver operator characteristic curve (ROC) analysis. RESULTS: Serum IL-41 levels in MG patients were higher than in HC, and were higher in Myasthenia Gravis Foundation of America (MGFA) III + IV group than that in MGFA I + II group. Serum IL-41 was positively correlated with MG-specific activities of daily living scale (MG-ADL), MGFA classification, platelet to lymphocyte ratio (PLR), and proportion of CD19+ B cells, while it was negatively correlated with high-sensitive C-reactive protein (hs-CRP) and circulatory plasma cells in MG patients. Serum IL-41 levels increased in patients who were treated with efgartigimod during the first cycle of therapy. However, compared to disease initiation, serum IL-41 levels decreased when clinical features steadily improved. ROC analysis showed that IL-41 had a diagnostic value for MG. CONCLUSION: The present findings suggested that serum IL-41 was increased in MG patients and was positively associated with the severity of the disease. IL-41 may be essential to the immunopathological mechanism of MG and a potential biomarker for MG.

A ratiometric fluorescence sensor based on carbon quantum dots realized the quantitative and visual detection of Hg2.

In this paper, based on the fluorescence of carbon quantum dots (CQDs) quenched by mercury ions (Hg2+ ) and the nonresponse of Hg2+ to rhodamine B fluorescence, a dual emission ratio fluorescence sensor was constructed to realize the quantitative detection of Hg2+ . Under excitation at 365 nm, the fluorescence spectrum showed double emission peaks at 437 nm and 590 nm, corresponding to the fluorescence emissions of CQDs and rhodamine B, respectively. This method quantitatively detected Hg2+ based on the linear relationship between the ratio of the intensities of the two emission peaks F437 /F590 and the concentration of Hg2+ . The detection range was 10-70 nM, and the limit of detection (S/N = 3) was 3.3 nM. In addition, this method could also realize the qualitative and semiquantitative detection of Hg2+ according to the fluorescence colour change of the probe under ultraviolet light. After various evaluations, the method could be successfully applied to the quantitative and visual detection of Hg2+ in tap water, and demonstrated excellent selectivity, anti-interference performance, and repeatability of the method.

A ratiometric electrochemiluminescent tetracycline assay based on the combined use of carbon nanodots, Ru(bpy)32+, and magnetic solid phase microextraction.

A method is described for combined magnetic solid phase microextraction and electrochemiluminescent (ECL) detection of the antibiotic tetracycline. A nanocomposite of type Fe3O4@SiO2@ZnO was used as the sorbent. Tetracycline has a strong affinity for Zn(II) ion and therefore is well extracted by this sorbent. The loaded sorbent can be magnetically removed. The extraction efficiency at a 1.0 µM tetracycline concentration is around 88%. Detection is based on the use of carbon nanodots that were prepared form urea and ethylenediaminetetraacetic acid as raw materials. The electrochemical probe Ru(bpy)32+ was added to generate double ECL when scanning the potential between -3.5 and + 2 V. The two ECL signals decreased with the increase of tetracycline concentration. Under optimized experimental conditions, the ratio of the two signals is linearly related to the logarithm of the tetracycline concentration in the range from 1.0 nM to 0.1 mM, with a 0.47 nM detection limit. The method was successfully applied to the determination of tetracycline in spiked milk. It exhibited good sensitivity, selectivity and accuracy due to ratiometric read-out and prior preconcentration of analyte. Graphical abstract Tetracycline (TC) has a strong affinity for Zn(II) ion and is well extracted by the Fe3O4@SiO2@ZnO nanocomposite. Ru(bpy)32+ can generate double electrochemiluminescence signals based on the use of carbon nanodots (C-dots) as coreactant. The two signals decrease with the increase of tetracycline concentration. [Ru(bpy)32+]* stands for excited state Ru(bpy)22+.