Th2-type inflammation instructs inflammatory dendritic cells to induce airway hyperreactivity.

Dendritic cells (DCs) play critical roles in determining the fate of CD4⁺ T cells. Among DC sub-populations, monocyte-derived inflammatory DCs (iDCs) have been shown to play an important role in the induction of adaptive immune responses under inflammatory conditions. Although previous studies have shown that DCs have an indispensable role in the induction of allergic airway inflammation and airway hyperreactivity (AHR) in murine asthma models, the precise roles of iDCs in the asthmatic responses remain largely unknown. We show here that T(h)2 cell-mediated inflammation in murine asthma models induces the expression of some markers of alternatively activated macrophage such as arginase 1 and resistin-like molecule-α in iDCs by a mechanism depending on the intrinsic expression of STAT6. In contrast, T(h)1 cell-mediated inflammation induces iDCs to express TNF-α and inducible nitric oxide synthase (iNOS), markers of TNF-α- and iNOS-producing DCs. Moreover, we show that iDCs under a T(h)2 environment play an important role in the induction of AHR, independently of allergic airway inflammation. Our results thus indicate the importance of iDCs in the induction of AHR as downstream effector cells in T(h)2 cell-mediated asthmatic responses.

Rapid collection of iron hydroxide for determination of Th isotopes in seawater.

This work introduces a novel method of recovery of iron hydroxide using a DIAION CR-20 chelating resin column to determine Th isotopes in seawater with a sector field (SF) inductively coupled plasma mass spectrometer (ICP-MS). Thorium isotopes in seawater were co-precipitated with iron hydroxide, and this precipitate was sent to chelating resin column. Ferric ions in the iron hydroxide were bonded to functional groups of the chelating resin directly, resulting in a pH increase of the effluent by release of hydroxide ion from the iron hydroxide. The co-precipitated thorium isotopes were quantitatively collected within the column, which indicated that thorium was retained on the iron hydroxide remaining on the chelating column. The chelating column quantitatively collected (232)Th with iron hydroxide in seawater at flow rates of 20-25 mL min(-1). Based on this flow rate, a 5 L sample was processed within 3-4 h. The >20 h aging of iron hydroxide tends to reduce the recovery of (232)Th. The rapid collection method was successfully applied to the determination of (230)Th and (232)Th in open-ocean seawater samples.

Correlation of radiographic progression with the cumulative activity of synovitis estimated by power Doppler ultrasound in rheumatoid arthritis: difference between patients treated with methotrexate and those treated with biological agents.

OBJECTIVE: Our prospective study aimed to demonstrate that the cumulative synovial power Doppler (PD) ultrasound scores correlate with radiographic progression better than conventional measures in patients with rheumatoid arthritis (RA). We also investigated the difference between antirheumatic agents. METHODS: Sixty-nine patients with RA who had recently received either methotrexate (MTX; n = 23), tumor necrosis factor (TNF) antagonists (n = 28), or tocilizumab (TCZ; n = 18) were enrolled. Patients underwent clinical, laboratory, and ultrasonographic assessment at baseline, 12 weeks, and 24 weeks. Radiographic damage was evaluated using van der Heijde modified total Sharp score (TSS) at baseline and 24 weeks. RESULTS: Fifty-seven patients continued the same treatment regimen for 24 weeks and completed the study, and 21 patients (36.8%) showed radiographic progression during the study period. In all patients, ΔTSS significantly correlated both with cumulative 28-joint Disease Activity Score-C-reactive protein (DAS28-CRP; ρ = 0.342, p = 0.009) and cumulative total PD scores (ρ = 0.357, p = 0.006). In MTX-treated patients, cumulative total PD scores significantly correlated with ΔTSS (ρ = 0.679, p = 0.004), whereas cumulative DAS28-CRP did not (ρ = 0.487, p = 0.056). However, cumulative total PD scores did not correlate with ΔTSS in TNF antagonist-treated or TCZ-treated patients. CONCLUSION: Our data confirm the evidence that synovial PD activity more accurately reflects active synovial inflammation (which actually causes joint destruction) than do conventional measures in patients treated with MTX. Our data also indicate that TNF antagonists can inhibit short-term radiographic progression in the presence of active synovitis.

[18F]FDG uptake in proximal muscles assessed by PET/CT reflects both global and local muscular inflammation and provides useful information in the management of patients with polymyositis/dermatomyositis.

OBJECTIVE: This study aimed to determine whether [(18)F]fluorodeoxyglucose-PET/CT ([(18)F]FDG-PET/CT) discriminates PM/DM from non-muscular diseases and also whether FDG uptake in proximal muscles reflects the activity and severity of muscular inflammation in PM/DM. METHODS: Twenty treatment-naïve PM/DM patients who underwent [(18)F]FDG-PET/CT were retrospectively identified by reviewing medical records. The same number of age- and sex-matched control patients with non-muscular diseases were also identified. Standardized uptake value (SUV) was calculated for each of the seven proximal muscles. For patient-based assessment, mean proximal muscle SUV was calculated by averaging the SUVs for these proximal muscles bilaterally. RESULTS: Mean proximal muscle SUVs were significantly greater in PM/DM patients than in control patients (median 1.05 vs 0.69, P < 0.001). Mean proximal muscle SUVs significantly correlated with mean proximal manual muscle test scores (ρ = 0.49, P = 0.028) and serum levels of creatine kinase (ρ = 0.54, P = 0.015) and aldolase (ρ = 0.64, P = 0.002). Furthermore, SUVs in proximal muscles from which biopsy specimens were obtained significantly correlated with histological grade for inflammatory cell infiltration (ρ = 0.66, P = 0.002). CONCLUSION: Our results suggest that [(18)F]FDG-PET/CT is useful in the diagnosis of PM/DM when inflammation in proximal muscles is globally assessed with quantitative measurements. Our results also indicate that local FDG uptake in a proximal muscle reflects the activity of inflammation in the same muscle and provides useful information in determining the region for muscle biopsy.

Ultrasound can improve the accuracy of the 2010 American College of Rheumatology/European League against rheumatism classification criteria for rheumatoid arthritis to predict the requirement for methotrexate treatment.

OBJECTIVE: The 2010 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) classification criteria for rheumatoid arthritis (RA) refer to a possible use of ultrasound "for confirmation of the clinical findings." We undertook this study to determine the optimized definition of ultrasound-detected synovitis for the 2010 ACR/EULAR criteria and to assess the impact of its use on the accuracy of RA classification. METHODS: One hundred nine patients with musculoskeletal symptoms for ≤3 years were enrolled in the study. Patients underwent clinical, laboratory, radiographic, and comprehensive ultrasonographic assessments at baseline and received routine management from expert rheumatologists who were blinded to the ultrasound findings. RESULTS: Sensitivity and specificity of the 2010 ACR/EULAR criteria using different definitions of synovitis to identify patients who developed a disease requiring methotrexate (MTX) treatment within 1 year were 58.5% and 79.4%, respectively, for clinical synovitis (tenderness or swelling), 78.0% and 79.4%, respectively, for ultrasound-detected synovitis with a gray-scale (GS) imaging score≥1 (GS≥1 ultrasound synovitis), and 56.1% and 93.7%, respectively, for GS≥2 ultrasound synovitis or a synovial power Doppler (PD) signal score≥1 (GS≥2/PD≥1 ultrasound synovitis). Receiver operating characteristic curve analysis for the criteria scores revealed the largest area under the curve with GS≥2/PD≥1 ultrasound synovitis. CONCLUSION: Ultrasound assessment improves the accuracy of the 2010 ACR/EULAR criteria for identifying patients with a disease requiring MTX treatment. Our data provide preliminary but vital information for the methodology to confirm the presence of synovitis using ultrasound in the 2010 ACR/EULAR criteria.