Magnetic Rolling Circle Amplification-Assisted Single-Particle Collision Immunosensor for Ultrasensitive Detection of Cardiac Troponin I.

Owing to its simplicity, high throughput, and ultrasensitivity, single-particle collision electrochemistry (SPCE) has attracted great attention in biosensing, especially labeled SPCE. However, the low signal conversion efficiency and much interference from complex samples limit its wide application. Here, a new and robust SPCE immunosensor was proposed for ultrasensitive cardiac troponin I (cTnI) detection by combining target-driven rolling circle amplification (RCA) with magnetic beads (MBs). Antibody-modified MBs have good stability, dispersity, and magnetic response capacity in complex samples, enabling efficient capture and separation of cTnI with high specificity and anti-interference ability. The presence of cTnI could specifically drive the formation of magnetic immunocomplexes followed by triggering RCA and enzyme digestion reaction. By using Pt nanoparticles (Pt NPs)-modified ssDNA as signal probes, one cTnI molecule could induce the release of 4.5 × 104 Pt NPs for collision experiments, greatly enhancing signal conversion efficiency and detection sensitivity. Based on the integration of MBs with RCA, the SPCE immunosensor realized 0.57 fg/mL cTnI detection with a wide linear range of 1 fg/mL to 50 ng/mL. Furthermore, cTnI detection in serum samples of myocardial infarction patients was successfully performed, demonstrating great application prospect of the SPCE immunosensor in clinical diagnosis.

Development of an activatable far-red fluorescent probe for rapid visualization of hypochlorous acid in live cells and mice with neuroinflammation.

Recent investigations have suggested that abnormally elevated levels of HOCl may be tightly related to the severity of neuroinflammation. Although some successes have been achieved, fluorescent probes with far-red fluorescence emission and capable of detecting HOCl with high specificity in pure aqueous solution are still urgently needed. Herein, a responsive far-red fluorescent probe, DCI-H, has been constructed to monitor HOCl activity in vivo and in vitro. DCI-H could rapidly respond to HOCl within 120 s and had a low detection limit for HOCl of 1.5 nM. Importantly, physiologically common interfering species, except for HOCl, did not cause a change in the fluorescence intensity of DCI-HOCl at 655 nm. The results of confocal imaging demonstrated the ability of DCI-H to visualize endogenous HOCl produced by MPO-catalyzed H2O2/Cl- and LPS stimulation. With the assistance of DCI-H, upregulation of HOCl levels was observed in the mice model of LPS-induced neuroinflammation. Thus, we believed that DCI-H provided a valuable tool for HOCl detection and diagnosis of inflammation-related diseases.

Construction of a coumarin-based fluorescent probe for accurately visualizing hydrogen sulfide in live cells and zebrafish.

Hydrogen sulfide (H2S), an important gas signaling molecule, is a regulator of many physiological processes, and its abnormal levels are closely related to the onset and progression of disease. It is vital to develop methods for specific tracking of H2S in clinical diagnosis and treatment. In this study, we designed an ultrasensitive and highly stable coumarin-based fluorescent probe Cou-H2S. Through the H2S-initiated tandem reaction, Cou-H2S successfully achieved highly selective and super-fast detection of H2S. Cou-H2S was successfully applied to the monitoring of endogenous and exogenous H2S at the cellular level and verified the validity of the detection of H2S in the LPS-induced zebrafish model. Therefore, Cou-H2S might provide new insights into the study of H2S-related diseases.

Analysis of status and influencing factors of mental health in patients with systemic lupus erythematosus.

BACKGROUND: Systemic lupus erythematosus (SLE) is a heterogeneous autoimmune disorder with varied clinical courses and prognoses, not only did the patients suffer from physical impairment, but also various physical and psychiatric comorbidities. Growing evidence have suggested that mental disorders in SLE patients, can lead to various adverse consequences. AIM: To explored the features and influencing factors of mental health in patients with SLE and clarifying the correlations between mental health and personality characteristics and perceived social support. The results would provide a basis for psychological intervention in patients with SLE. METHODS: The clinical data of 168 patients with SLE admitted at the First Affiliated Hospital of Hainan Medical University between June 2020 and June 2022 were collected. Psychological assessment and correlation analysis were conducted using the Symptom Checklist-90 (SCL-90) and Perceived Social Support Scale, and the collected data were compared with the national norms in China. The relevant factors influencing mental health were identified by statistical analysis. A general information questionnaire, the Revised Life Orientation Test, and Short-Form 36-Item Health Survey were employed to assess optimism level and quality of life (QoL), respectively. RESULTS: Patients with SLE obtained higher scores for the somatization, depression, anxiety, and phobic anxiety subscales than national norms (P < 0.05). A correlation was identified between total social support and total SCL-90 score or each subscale (P < 0.05). The factors significantly affecting patients' mental health were hormone dosage and disease activity index (DAI) (P < 0.05). The average optimism score of patients with SLE was 14.36 ± 4.42, and 30 cases were in the middle and lower levels. A positive correlation was found between optimism level and QoL scores. CONCLUSION: Patients with SLE develop psychological disorders at varying degrees, which are significantly influenced by hormone dosage and DAI. Patients' mental health should be closely monitored during clinical diagnosis and treatment and provided adequate support in establishing positive, healthy thinking and behavior patterns and improving their optimism level and QoL.

Downregulation of miR-137 Facilitates CD4+ T Cell Pyroptosis in Systemic Lupus Erythematosus via Stimulating AMPK Pathway.

Objective: From the pathogenic mechanism point of view, systemic lupus erythematosus (SLE) features prominently in T lymphocyte apoptosis. Yet the regulatory mechanism underlying SLE cell apoptosis remains to be explored. This research intends to clarify the role played by miR-137 in SLE and the underlying mechanisms. Methods: Twenty SLE patients (SLE group) and twenty healthy controls (control group) were selected, from whom peripheral blood CD4+ T cells were isolated via magnetic-activated cell sorting. Reverse transcription-polymerase chain reaction (RT-PCR) quantified miR-137 and AMP-activated protein kinase (AMPK) in CD4+ T cells. Further, transfection of miR-137 mimics and inhibitors into CD4+ T cells was carried out to alter miR levels. Levels of pyroptosis, apoptosis, and inflammatory- and pyroptosis-related proteins were determined through PI staining, flow cytometry, and Western blotting, respectively. A luciferase reporter gene assay identified the targeting relation between miR-137 and AMPK. Results: SLE patients showed downregulated miR-137 and upregulated AMPK in CD4+ T cells than controls. miR-137 upregulation by miR-137 mimic transfection inhibited Jurkat cell pyroptosis and apoptosis at both mRNA and protein levels and suppressed NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) inflammasome activity and pyroptosis-related protein gasdermin D (GSDMD), while miR-137 inhibitor transfection contributed to completely opposite effects. miR-137 directly targeted AMPK, as indicated by the luciferase reporter gene assay. Furthermore, miR-137 inhibitor intervention induced healthy CD4+ T cell pyroptosis and apoptosis via mediating AMPK, whereas miR-137 mimic transfection into CD4+ T cells of SLE patients leads to opposite results. Conclusion: Upregulating miR-137 inhibits CD4+ T cell pyroptosis in SLE patients by modulating the AMPK pathway, suggesting the potential diagnostic and therapeutic role of miR-137 in SLE.

Development of an activatable red emissive fluorescent probe for imaging hydrogen disulfide upregulation in living cells and zebrafish.

As a member of reactive sulfur molecules, hydrogen polysulfide (H2Sn) plays a vital role in cell protection, anti-oxidative stress and regulation of redox signaling. The highly selective and sensitive detection of H2Sn was still challenging due to its special nucleophilic and electrophilic reactivity. By incorporating phenyl 2-(benzoylthio) benzoate into semi-naphthofluorescein, we developed a novel red emissive fluorescent probe SNAFL-H2Sn for the detection of a representative H2Sn (e. g. H2S2). The addition of H2S2 would rapidly trigger SNAFL-H2Sn to produce significant turn-on fluorescence signal changes at 626 nm with a linear response over a range of 2-30 µM and a detection limit of 16 nM. SNAFL-H2Sn was capable of mapping exogenous and endogenous H2S2 in living cells and zebrafish. Moreover, SNAFL-H2Sn was applied to detect endogenous H2S2 under atorvastatin stimulation. The present study demonstrated that SNAFL-H2Sn potentially served as a promising tool for interrogating H2Sn functions in biological systems.

Changes in the balance between Treg and Th17 cells in patients with chronic hepatitis B.

The purpose of this study was to explore the role of Treg cells, Th17 cells and cytokines associated with Treg/Th17 differentiation in the occurrence, development and outcome of chronic hepatitis B (CHB). To do so, we detected populations of Treg and Th17 cells and their associated cytokines in the peripheral blood of CHB patients. The populations of Treg cells (CD4(+)CD25(high)CD127(low) T cells) and Th17 cells (CD3(+)CD8(-)IL-17(+) T cells) were analyzed in 46 patients with low to moderate chronic hepatitis B (CHB-LM), 24 patients with severe chronic hepatitis B (CHB-S) and 20 healthy controls (HC) using flow cytometry. The levels of cytokines associated with Treg/Th17 differentiation, including IL-10, TGF-ß1, IL-17 and IL-23, were measured by enzyme-linked immunosorbent assay (ELISA). Our study showed that the imbalance of Treg and Th17 cells might play an important role in the occurrence, development and outcome of CHB.

Dynamic Changes of Treg and Th17 Cells and Related Cytokines Closely Correlate With the Virological and Biochemical Response in Chronic Hepatitis B Patients Undergoing Nucleos(t)ide Analogues Treatment.

BACKGROUND: The restoration of HBV-specific T-cell response during antiviral therapy is associated with CD4+T-cell activity. Treg cells and Th17 cells are subtypes of CD4+T cell. However, it has remained unknown how the Treg and Th17 cells and their associated cytokines affect nucleos(t)ide analogues (NA) antiviral efficacy. OBJECTIVES: The aim of the present study was to provide a new insight to evaluate the NA antiviral therapy for patients with chronic hepatitis B (CHB). PATIENTS AND METHODS: Forty-four CHB patients hospitalized between July 2010 and August 2011 were enrolled in this study. They were received NA (entecavir, lamivudine and adefovir) treatment for 14.42 ± 13.08 weeks, and the peripheral blood was collected. The frequencies of Treg and Th17 cells were detected by flow cytometric analysis, and the levels of IL-10, TGF-ß1, IL-17 and IL-23 were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: In complete and partial-responders, Treg cells frequencies and IL-10, TGF-ß1, IL-23 levels were all decreased significantly after NA therapy, while Th17 cells and the IL-17 levels were increased slightly. Treg/Th17 ratio was only dramatically declined in complete-responders. But there was no significant difference in non-responders. Either HBV DNA decreased by at least 2 log copies /mL or ALT turned to normal level, Treg cells frequencies and IL-10, TGF-ß1, IL-23 levels were significantly reduced. Meanwhile, Treg cells were positively correlated with HBV DNA and ALT. CONCLUSIONS: The changes of Treg and Th17 cells and their associated cytokines were related to virological and biochemical responses.