Identification of risk factors for treatment resistance and relapse would be crucial to personalization therapy in patients with myeloperoxidase (MPO)-anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (MPO-AAV). Current evidence with regard to the risk factors for treatment resistance and relapse remains limited and inconclusive. We aimed to assess the predictors for treatment resistance and relapse in a single-center cohort of Chinese patients with MPO-AAV in this study. In total, 184 patients with MPO-AAV were included. Treatment resistance occurred in 64 (34.9%) of 184 patients and was positively associated with lung involvement (odds ratio [OR] 3.581, 95% CI 1.137-11.278, p = 0.029) and the initial serum creatinine level (OR 1.004, 95% CI 1.001-1.007, p = 0.010) and was negatively associated with platelet (OR 0.992, 95% CI 0.987-0.998, p = 0.007) and serum C3 levels (OR 0.998, 95% CI 0.996-0.999, p = 0.004). Relapse occurred in 29 (24.17%) of 120 patients in whom remission was achieved and was independently associated with lung involvement (hazard ratio [HR] 4.595, 95% CI 1.272-16.599, p = 0.020) and cardiovascular involvement (HR 3.689, 95% CI 1.237-11, p = 0.019,). The serum globulin was demonstrated to be negatively associated with relapse independently (HR 0.876; 95% CI 0.806-0.953; p = 0.002). This retrospective study of MPO-AAV patients in a single Chinese center suggests that treatment resistance was positively associated with lung involvement and the initial serum creatinine level and was negatively associated with platelet and serum C3 levels. Lung involvement and cardiovascular involvement were associated with an increased risk of relapse, while the higher serum globulin was demonstrated to be in association with a decreased risk of relapse.OBJECTIVE To develop a three-dimensional (3D) high-resolution free-breathing magnetization transfer ratio (MTR) sequence for contrast-free assessment of myocardial infarct and coronary vein anatomy. MATERIALS AND METHODS Two datasets with and without off-resonance magnetization transfer preparation were sequentially acquired to compute MTR. 2D image navigators enabled beat-to-beat translational and bin-to-bin non-rigid motion correction. Two different imaging sequences were explored. MTR scar localization was compared against 3D late gadolinium enhancement (LGE) in a porcine model of myocardial infarction. MTR variability across the left ventricle and vessel sharpness in the coronary veins were evaluated in healthy human subjects. RESULTS A decrease in MTR was observed in areas with LGE in all pigs (non-infarct 25.1 ± 1.7% vs infarct 16.8 ± 1.9%). The average infarct volume overlap on MTR and LGE was 62.5 ± 19.2%. In humans, mean MTR in myocardium was between 37 and 40%. Spatial variability was between 15 and 20% of the mean value. 3D whole heart MT-prepared datasets enabled coronary vein visualization with up to 8% improved vessel sharpness for non-rigid compared to translational motion correction. DISCUSSION MTR and LGE showed agreement in infarct detection and localization in a swine model. Free-breathing 3D MTR maps are feasible in humans but high spatial variability was observed. Further clinical studies are warranted.OBJECTIVE In dynamic susceptibility contrast MRI (DSC-MRI), an arterial input function (AIF) is required to quantify perfusion. However, estimation of the concentration of contrast agent (CA) from magnitude MRI signal data is challenging. A reasonable alternative would be to quantify CA concentration using quantitative susceptibility mapping (QSM), as the CA alters the magnetic susceptibility in proportion to its concentration. MATERIAL AND METHODS AIFs with reasonable appearance, selected on the basis of conventional criteria related to timing, shape, and peak concentration, were registered from both ΔR2* and QSM images and mutually compared by visual inspection. Both ΔR2*- and QSM-based AIFs were used for perfusion calculations based on tissue concentration data from ΔR2*as well as QSM images. RESULTS AIFs based on ΔR2* and QSM data showed very similar shapes and the estimated cerebral blood flow values and mean transit times were similar. Analysis of corresponding ΔR2* versus QSM-based concentration estimates yielded a transverse relaxivity estimate of 89 s-1 mM-1, for voxels identified as useful AIF candidate in ΔR2* images according to the conventional criteria. DISCUSSION Interestingly, arterial concentration time curves based on ΔR2* versus QSM data, for a standard DSC-MRI experiment, were generally very similar in shape, and the relaxivity obtained in voxels representing blood was similar to tissue relaxivity obtained in previous studies.Cyclo Olefin Polymer (COP) based microbioreactors on a microfluidic chip were produced in house by hot-embossing and thermo-compression bonding methods. The chip allows two different experiments to be performed on trapped cells at the same time. On one side of the chip, red fluorescent protein (RFP) tagged nucleolar Nop56 protein was used to track changes in cell cycle as well as protein synthesis within the yeast cells under the application of the anti-tumor agent hydroxyurea (HU). learn more Simultaneously, on the other side of the chip, the response of yeast cells to the drug metformin, mTOR inhibitor, was investigated to reveal the role of TOR signaling in ribosome biogenesis and cell proliferation. The results of 20 h long experiments are captured by taking brightfield and fluorescent microscopy images of the trapped cells every 9 min. The expression of Nop56 protein of ribosome assembly and synthesis was densely observed during G1 phase of cell cycle, and later towards the end of cell cycle the ribosomal protein expression slowed down. Under HU treatment, the morphology of yeast cells changed, but after cessation of HU, the biomass synthesis rate was sustained as monitored by the cell perimeter. Under metformin treatment, the perimeters of single cells were observed to decrease, implying a decrease in biomass growth; however these cells continued their proliferation during and after the drug application. The relation between ribosome biogenesis and cell cycle was successfully investigated on single cell basis, capturing cell-to-cell variations, which cannot be tracked by regular macroscale bioreactors.