A novel model to assess disease activity in Takayasu arteritis based on 18F-FDG-PET/CT: a Chinese cohort study.

OBJECTIVE: To investigate the utility of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) in assessing disease activity in Takayasu arteritis (TA). METHODS: Ninety-one patients with TA were recruited from a Chinese cohort. Clinical data, acute-phase reactants and 18F-FDG-PET/CT findings were simultaneously recorded. The value of using 18F-FDG-PET/CT to identify active disease was evaluated, using ESR as a reference. Disease activity assessment models were constructed and concordance index (C-index), net reclassification index (NRI), and integrated discrimination index (IDI) were evaluated to compare the benefits of the new modes with ESR and the Kerr score. RESULTS: In total, 64 (70.3%) cases showed active disease. Higher levels of ESR and CRP, and lower IL-2 receptor (IL-2R) levels were observed in active cases. 18F-FDG-PET/CT parameters measured by determining the standard uptake value (SUV), including SUVmean, SUVratio1, SUVratio2, sum of SUVmean and sum of SUVmax, were significantly higher in active disease groups. The C-index threshold of ESR to indicate active disease was 0.78 (95% CI: 0.69, 0.88). The new activity assessment model combining ESR, sum of SUVmean and IL-2R showed significant improvement in C-index over the ESR method (0.96 vs 0.78, P < 0.01; NRI 1.63, P < 0.01; and IDI 0.48, P < 0.01). The new model also demonstrated modest superiority to the Kerr score assessment (0.96 vs 0.87, P = 0.03; NRI 1.19, P < 0.01; and IDI 0.33, P < 0.01). CONCLUSIONS: A novel 18F-FDG-PET/CT-based method that involves combining the sum of SUVmean with ESR score and IL-2R levels demonstrated superiority in identifying active TA compared with conventional methods.

Potential risk of hyperuricemia: leading cardiomyocyte hypertrophy by inducing autophagy.

BACKGROUND: Clinical studies have shown that hyperuricemia is associated with many cardiovascular diseases; however, the mechanisms involved remain unclear. In this study, we investigated the effect of uric acid on cardiomyocytes and the underlying mechanism. METHODS AND RESULTS: H9c2 cardiomyocytes were treated with various concentrations of uric acid. 3-Methyladenine (3-MA) or Compound C was added before treatment with uric acid. The expression of myocardial hypertrophy-related genes was measured using polymerase chain reaction (PCR). The cell surface area was calculated using ImageJ Software. Western blotting was used to measure the protein levels. Uric acid increased the gene expression of Nppa, Nppb, and Myh5, which are involved in myocardial hypertrophy, and the relative cell surface area of cardiomyocytes in a dose-dependent manner. Consistently, the ratio of LC3II/I, which is a biomarker of autophagy, increased dose-dependently, whereas the protein level of p62, a protein that is degraded by autophagy, decreased. 3-MA, an autophagy inhibitor, rescued uric acid-induced myocardial hypertrophy. Treatment with uric acid increased the level of phosphorylated adenosine monophosphate kinase (AMPK), as well as its downstream effector unc-51-like kinase (ULK1). Pharmacological inhibition of AMPK by Compound C attenuated the uric acid-induced activation of autophagy and myocardial hypertrophy. CONCLUSIONS: Uric acid induces myocardial hypertrophy by activating autophagy via the AMPK-ULK1 signaling pathway. Decreasing the serum uric acid level may therefore be clinically beneficial in alleviating cardiac hypertrophy.

The effects of dopamine receptor 2 expression on B cells on bone metabolism and TNF-α levels in rheumatoid arthritis.

BACKGROUND: Dopamine receptor 2 (DR2) expressions on B cells from Rheumatoid arthritis (RA) patients has been found to be negatively correlated with disease activity and can potentially predict the response to treatment. This study aimed to investigate the role of B cell DR2 expression on bone remodeling in RA. METHODS: Patients with RA (n = 14) or osteoarthritis (OA; n = 12), and healthy controls (n = 12) were recruited for this study. Dopamine receptor (DR) 2 expression was assessed using flow cytometry. Pro-inflammatory cytokines, including interleuin(IL)-1ß, IL-6, IL-17, and tumor necrosis factor(TNF)-α, and bone turnovers, including osteocalcin (OC),serum procollagen type I N propeptide (PINP), C-terminal telopeptide of type I collagen (ß-CTX), collagen type I cross-linked telopeptide (ICTP), as well as matrix metalloproteinase-3 (MMP-3) and osteoprotegerin (OPG) were measured by electrochemiluminescence, chemiluminescence, or enzyme-linked immunosorbent assay. DR2 expression on synovial B cells from 4 RA patients and 3 OA patients was detected by immunofluorescence. RESULTS: There were more DR2(+)CD19(+) B cells in synovial tissues from RA patients than in those from OA patients. The frequency of peripheral B cells that expressed DR2 was positively correlated with plasma TNF-α level. Levels of ICTP and MMP-3 were significantly higher, and OPG were lower in RA patients compared to those in the OA group and healthy controls (all P < 0.05). CONCLUSION: The frequency of B cells that expressed DR2 showed a correlation with levels of the pro-inflammatory cytokine TNF-α. DR2(+)CD19(+) B cells in synovial tissues might have a role in bone metabolism and TNF-α production.

Serum uric acid and its relationship with cardiovascular risk profile in Chinese patients with early-onset coronary artery disease.

The prevalence of coronary artery disease (CAD) is growing in the young population. We aimed to investigate the association between serum uric acid (SUA) levels and cardiovascular involvement in individuals under 45 years old diagnosed with early-onset CAD (EOCAD). Seven hundred eighty-six EOCAD patients were recruited and stratified into four groups by SUA levels. General information, serum indicators, and results of coronary angiography and echocardiography were recorded. The associations between SUA levels were explored by univariate and multivariate logistic regressions. With the increasing of SUA levels, the prevalence of hypertension and hyperlipidemia, triple branches involved, heart failure, and cardiac enlargement of left ventricle (LV), left atrium (LA), and right ventricle (RV) were significantly higher (all P < 0.05). The fourth group (SUA >8 mg/dl) had the highest proportions than other groups (all P < 0.05). After controlling potential confounders, multiple logistic regression analysis showed that odds ratios of SUA >8 mg/dl were 2.345 for triple branches involved (95 % confidence interval (CI) 1.335-4.119), 4.168 for heart failure (95 % CI 1.599-10.862), and 4.122 for LV enlargement (95 % CI 1.874-9.065) (P < 0.05). SUA >8 mg/dl was independently associated with triple branches involvement, heart failure and LV enlargement in Chinese EOCAD patients. Higher SUA level might play an important role in cardiac dysfunction and severity of EOCAD.