Abstract Background Large cohort studies provide conflicting evidence regarding the potential for oral macrolide antibiotics to increase the risk of serious cardiac events. Objectives This study ...performed a meta-analysis to examine the link between macrolides and risk of sudden cardiac death (SCD) or ventricular tachyarrhythmias (VTA), cardiovascular death, and death from any cause. Methods We performed a search of published reports by using MEDLINE (January 1, 1966, to April 30, 2015) and EMBASE (January 1, 1980, to April 30, 2015) with no restrictions. Studies that reported relative risk (RR) estimates with 95% confidence intervals (CIs) for the associations of interest were included. Results Thirty-three studies involving 20,779,963 participants were identified. Patients taking macrolides, compared with those who took no macrolides, experienced an increased risk of developing SCD or VTA (RR: 2.42; 95% CI: 1.61 to 3.63), SCD (RR: 2.52; 95% CI: 1.91 to 3.31), and cardiovascular death (RR: 1.31; 95% CI: 1.06 to 1.62). No association was found between macrolides use and all-cause death or any cardiovascular events. The RRs associated with SCD or VTA were 3.40 for azithromycin, 2.16 for clarithromycin, and 3.61 for erythromycin, respectively. RRs for cardiovascular death were 1.54 for azithromycin and 1.48 for clarithromycin. No association was noted between roxithromycin and adverse cardiac outcomes. Treatment with macrolides is associated with an absolute risk increase of 118.1 additional SCDs or VTA, and 38.2 additional cardiovascular deaths per 1 million treatment courses. Conclusions Administration of macrolide antibiotics is associated with increased risk for SCD or VTA and cardiovascular death but not increased all-cause mortality.
Myocarditis refers to an autoimmune inflammatory response of the myocardium with characterization of self-reactive CD4+ T cell activation, which lacks effective treatment and has a poor prognosis. ...Acacetin is a natural flavonoid product that has been reported to have anti-inflammatory effects. However, acacetin has not been investigated in myocarditis.
Oral acacetin treatment was administered in an experimental autoimmune myocarditis model established with myosin heavy chain-alpha peptide. Echocardiography, pathological staining, and RT-qPCR were used to detect cardiac function, myocardial injury, and inflammation levels. Flow cytometry was utilized to detect the effect of acacetin on CD4+ T cell function. RNA-seq, molecular docking, and microscale thermophoresis (MST) were employed to investigate potential mechanisms. Seahorse analysis, mitoSOX, JC-1, and mitotracker were utilized to detect the effect of acacetin on mitochondrial function.
Acacetin attenuated cardiac injury and fibrosis as well as heart dysfunction, and reduced cardiac inflammatory cytokines and ratio of effector CD4+ T and Th17 cells. Acacetin inhibited CD4+ T cell activation, proliferation, and Th17 cell differentiation. Mechanistically, the effects of acacetin were related to reducing mitochondrial complex II activity thereby inhibiting mitochondrial respiration and mitochondrial reactive oxygen species in CD4+ T cells.
Acacetin may be a valuable therapeutic drug in treating CD4+ T cell-mediated myocarditis.
BACKGROUND—Postoperative atrial fibrillation is a frequent complication in cardiac surgery. The aberrant activation of signal transducer and activator of transcription 3 (STAT3) contributes to the ...pathogenesis of atrial fibrillation. MicroRNA-21 (miR-21) promotes atrial fibrosis. Recent studies support the existence of reciprocal regulation between STAT3 and miR-21. Here, we test the hypothesis that these 2 molecules might form a feedback loop that contributes to postoperative atrial fibrillation by promoting atrial fibrosis.
METHODS AND RESULTS—A sterile pericarditis model was created using atrial surfaces dusted with sterile talcum powder in rats. The inflammatory cytokines interleukin (IL)-1β, IL-6, transforming growth factor-β, and tumor necrosis factor-α, along with STAT3 and miR-21, were highly upregulated in sterile pericarditis rats. The inhibition of STAT3 by S3I-201 resulted in miR-21 downregulation, which ameliorated atrial fibrosis and decreased the expression of the fibrosis-related genes, α-smooth muscle actin, collagen-1, and collagen-3; reduced the inhomogeneity of atrial conduction; and attenuated atrial fibrillation vulnerability. Meanwhile, treatment with antagomir-21 decreased STAT3 phosphorylation, alleviated atrial remodeling, abrogated sterile pericarditis–induced inhomogeneous conduction, and prevented atrial fibrillation promotion. The culturing of cardiac fibroblasts with IL-6 resulted in progressively augmented STAT3 phosphorylation and miR-21 levels. S3I-201 blocked IL-6 induced the expression of miR-21 and fibrosis-related genes in addition to cardiac fibroblast proliferation. Transfected antagomir-21 decreased the IL-6–induced cardiac fibroblast activation and STAT3 phosphorylation. The overexpression of miR-21 in cardiac fibroblasts caused the upregulation of STAT3 phosphorylation, enhanced fibrosis-related genes, and increased cell numbers.
CONCLUSIONS—Our results have uncovered a novel reciprocal loop between STAT3 and miR-21 that is activated after heart surgery and can contribute to atrial fibrillation.
Atrial fibrillation (AF) is a very common cardiac arrhythmia with an estimated prevalence of 33.5 million patients globally. It is associated with an increased risk of death, stroke and peripheral ...embolism. Although genetic studies have identified a growing number of genes associated with AF, the definitive impact of these genetic findings is yet to be established. Several mechanisms, including electrical, structural and neural remodelling of atrial tissue, have been proposed to contribute to the development of AF. Despite over a century of exploration, the molecular and cellular mechanisms underlying AF have not been fully established. Current antiarrhythmic drugs are associated with a significant rate of adverse events and management of AF using ablation is not optimal, especially in cases of persistent AF. This review discusses recent advances in our understanding and management of AF, including new concepts of epidemiology, genetics and pathophysiological mechanisms. We review the current status of antiarrhythmic drug therapy for AF, new potential agents, as well as mechanism-based AF ablation. This article is part of the theme issue 'The heartbeat: its molecular basis and physiological mechanisms'.
Prevalent irregular rainfall, flooding for weed control, and unleveled fields in the middle and lower reaches of the Yangtze River all contribute to flooding stress on germination and growth of ...direct‐seeded rice (Oryza sativa L.). Herein, some experiments were conducted so as to assess the effects of seed priming with selenium (Se) on the germination and growth of rice under hypoxia. The experiment was arranged in a completely randomized factorial design with two factors and five replicates. Factors included Se concentration (0, 30, and 60 μmol/L) and duration of flooding stress (0, 2, 4, and 8 days). The experimental results showed that Se accelerated seed germination and increased emergence index and final emergence percentage. Additionally, Se increased shoot and root lengths and dry weights, but high Se concentration (60 μmol/L) reduced 18‐day‐old seedling dry weight under long‐term flooding (8 days). Furthermore, Se reduced malondialdehyde content and increased starch hydrolysis efficiency in seeds, superoxide dismutase, peroxidase, catalase, and glutathione peroxidase activities and seedling soluble protein and total chlorophyll contents. Se improved seedling total Se and organic Se contents while increasing total dry weight and yield. Notably, the highest yield was obtained after a 4‐day flooding period. Although Se priming favored rice seedling emergence and growth under flooding conditions, Se concentrations equal or above 60 μmol/L increased the risk of seedling death during long‐term flooding (≥8 days).
Diphenyl phosphine oxide-1 (DPO-1) is a potent Kv1.5 channel inhibitor that has therapeutic potential for the treatment of atrial fibrillation. Many other Kv1.5 channel blockers also potently inhibit ...the Kv1.3 channel, but whether DPO-1 blocks Kv1.3 channels has not been investigated. The Kv1.3 channel is highly expressed in activated T cells, which is considered a favorable target for immunomodulation. Accordingly, we hypothesized that DPO-1 may exert immunosuppressive and anti-inflammatory effects by inhibiting Kv1.3 channel activity. In this study, DPO-1 blocked Kv1.3 current in a voltage-dependent and concentration-dependent manner, with IC₅₀ values of 2.58 µM in Jurkat cells and 3.11 µM in human peripheral blood T cells. DPO-1 also accelerated the inactivation rate and negatively shifted steady-state inactivation. Moreover, DPO-1 at 3 µM had no apparent effect on the Ca²⁺ activated potassium channel (K(Ca)) current in both Jurkat cells and human peripheral blood T cells. In Jurkat cells, pre-treatment with DPO-1 for 24 h decreased Kv1.3 current density, and protein expression by 48±6% and 60±9%, at 3 and 10 µM, respectively (both p<0.05). In addition, Ca²⁺ influx to Ca²⁺-depleted cells was blunted and IL-2 production was also reduced in activated Jurkat cells. IL-2 secretion was also inhibited by the Kv1.3 inhibitors margatoxin and charybdotoxin. Our results demonstrate for the first time that that DPO-1, at clinically relevant concentrations, blocks Kv1.3 channels, decreases Kv1.3 channel expression and suppresses IL-2 secretion. Therefore, DPO-1 may be a useful treatment strategy for immunologic disorders.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background:
We applied a network Mendelian randomization (MR) framework to determine the causal association between body mass index (BMI) and coronary heart disease (CHD) and explored whether ...glycated hemoglobin (HbA1c) and lipid parameters (total cholesterol, TC; low-density lipoprotein cholesterol, LDL; high-density lipoprotein cholesterol, HDL; triglycerides, TG) serve as causal mediators from BMI to CHD by integrating summary-level genome-wide association study data.
Methods:
Network MR analysis, an approach using genetic variants as the instrumental variables for both the exposure and mediator to infer causality was performed. Summary statistics from the GIANT consortium were used (n = 152,893) for BMI, CARDIoGRAMplusC4D consortium data were used (n = 184,305) for CHD, Global Lipids Genetics Consortium data were used (n = 108,363) for TC, LDL, HDL and TG, and MAGIC consortia data were used (n = 108,363) for HbA1c.
Results:
The inverse-variance-weighted-method estimate indicated that the odds ratio (95% confidence interval) for CHD was 1.562 (1.391–1.753) per 1 standard deviation (kg/m2) increase in BMI. Results were consistent in MR Egger method and weighted-median methods. MR estimate indicated that BMI was positively associated with HbA1c and TG, and negatively associated with HDL, but was not associated with TC or LDL. Moreover, HbA1c, TC, LDL, and TG were positively associated with CHD, yet there was no causal association between HDL and CHD. HbA1c was positively associated with TC, LDL, and HDL, but was not associated with TG.
Conclusions:
Higher BMI conferred an increased risk of CHD, which was partially mediated by HbA1c and lipid parameters. HbA1c and TG might be the main mediators in the link from BMI to CHD.
Severe fever with thrombocytopenia syndrome (SFTS) virus (SFTSV) is an emerging tick-borne virus with high fatality and an expanding endemic. Currently, effective anti-SFTSV intervention remains ...unavailable. Favipiravir (T-705) was recently reported to show in vitro and in animal model antiviral efficacy against SFTSV. Here, we conducted a single-blind, randomized controlled trial to assess the efficacy and safety of T-705 in treating SFTS (Chinese Clinical Trial Registry website, number ChiCTR1900023350). From May to August 2018, laboratory-confirmed SFTS patients were recruited from a designated hospital and randomly assigned to receive oral T-705 in combination with supportive care or supportive care only. Fatal outcome occurred in 9.5% (7/74) of T-705 treated patients and 18.3% (13/71) of controls (odds ratio, 0.466, 95% CI, 0.174-1.247). Cox regression showed a significant reduction in case fatality rate (CFR) with an adjusted hazard ratio of 0.366 (95% CI, 0.142-0.944). Among the low-viral load subgroup (RT-PCR cycle threshold ≥26), T-705 treatment significantly reduced CFR from 11.5 to 1.6% (P = 0.029), while no between-arm difference was observed in the high-viral load subgroup (RT-PCR cycle threshold <26). The T-705-treated group showed shorter viral clearance, lower incidence of hemorrhagic signs, and faster recovery of laboratory abnormities compared with the controls. The in vitro and animal experiments demonstrated that the antiviral efficacies of T-705 were proportionally induced by SFTSV mutation rates, particularly from two transition mutation types. The mutation analyses on T-705-treated serum samples disclosed a partially consistent mutagenesis pattern as those of the in vitro or animal experiments in reducing the SFTSV viral loads, further supporting the anti-SFTSV effect of T-705, especially for the low-viral loads.
Background:
Sarcomas are heterogeneous rare malignancies constituting approximately 1% of all solid cancers in adults and including more than 70 histological and molecular subtypes with different ...pathological and clinical development characteristics.
Method:
We identified prognostic biomarkers of sarcomas by integrating clinical information and RNA-seq data from TCGA and GEO databases. In addition, results obtained from cell cycle, cell migration, and invasion assays were used to assess the capacity for Tanespimycin to inhibit the proliferation and metastasis of sarcoma.
Results:
Sarcoma samples (
N
= 536) were divided into four pathological subtypes including DL (dedifferentiated liposarcoma), LMS (leiomyosarcoma), UPS (undifferentiated pleomorphic sarcomas), and MFS (myxofibrosarcoma). RNA-seq expression profile data from the TCGA dataset were used to analyze differentially expressed genes (DEGs) within metastatic and non-metastatic samples of these four sarcoma pathological subtypes with DEGs defined as metastatic-related signatures (MRS). Prognostic analysis of MRS identified a group of genes significantly associated with prognosis in three pathological subtypes: DL, LMS, and UPS.
ISG15, NUP50, PTTG1, SERPINE1
, and
TSR1
were found to be more likely associated with adverse prognosis. We also identified Tanespimycin as a drug exerting inhibitory effects on metastatic LMS subtype and therefore can serve a potential treatment for this type of sarcoma.
Conclusions:
These results provide new insights into the pathogenesis, diagnosis, treatment, and prognosis of sarcomas and provide new directions for further study of sarcoma.
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