Machine learning-based prediction of relapse in rheumatoid arthritis patients using data on ultrasound examination and blood test

Recent effective therapies enable most rheumatoid arthritis (RA) patients to achieve remission; however, some patients experience relapse. We aimed to predict relapse in RA patients through machine learning (ML) using data on ultrasound (US) examination and blood test. Overall, 210 patients with RA in remission at baseline were dichotomized into remission (n = 150) and relapse (n = 60) based on the disease activity at 2-year follow-up. Three ML classifiers [Logistic Regression, Random Forest, and extreme gradient boosting (XGBoost)] and data on 73 features (14 US examination data, 54 blood test data, and five data on patient information) at baseline were used for predicting relapse. The best performance was obtained using the XGBoost classifier (area under the receiver operator characteristic curve (AUC) = 0.747), compared with Random Forest and Logistic Regression (AUC = 0.719 and 0.701, respectively). In the XGBoost classifier prediction, ten important features, including wrist/metatarsophalangeal superb microvascular imaging scores, were selected using the recursive feature elimination method. The performance was superior to that predicted by researcher-selected features, which are conventional prognostic markers. These results suggest that ML can provide an accurate prediction of relapse in RA patients, and the use of predictive algorithms may facilitate personalized treatment options

Tumor suppressor REIC/Dkk-3 interacts with the dynein light chain, Tctex-1

Persistent hepatitis C virus (HCV) infection causes chronic liver diseases and is a global health problem. HuH-7 hepatoma-derived cells are widely used as the only cell-based HCV replication system for HCV research, including drug assays. Recently, using different hepatoma Li23-derived cells, we developed an HCV drug assay system (ORL8), in which the genome-length HCV RNA (O strain of genotype 1b) encoding renilla luciferase replicates efficiently. In this study, using the HuH-7-derived OR6 assay system that we developed previously and the ORL8 assay system, we evaluated 26 anti-HCV reagents, which other groups had reported as anti-HCV candidates using HuH-7-derived assay systems other than ORB. The results revealed that more than half of the reagents showed different anti-HCV activities from those in the previous studies, and that anti-HCV activities evaluated by the ORB and ORL8 assays were also frequently different. In further evaluation using the HuH-7-derived AH1R assay system, which was developed using the AH1 strain of genotype 1b, several reagents showed different anti-HCV activities in comparison with those evaluated by the OR6 and ORL8 assays. These results suggest that the different activities of anti-HCV reagents are caused by the differences in cell lines or HCV strains used for the development of assay systems. Therefore, we conclude that plural HCV assay systems developed using different cell lines or HCV strains are required for the objective evaluation of anti-HCV reagents

Role of JAK-STAT signaling in the pathogenic behavior of fibroblast-like synoviocytes in rheumatoid arthritis: Effect of the novel JAK inhibitor peficitinib

Rheumatoid arthritis (RA) fibroblast-like synoviocytes (RA-FLS) play a crucial role in the pathogenesis of RA. RA-FLS display passive pro-inflammatory responses and self-directed aggressive responses, such as pro-inflammatory mediator production, reduced apoptosis and formation of a thickened synovial lining. Evidence suggests a role for Janus kinase (JAK)-signal transducer and transcriptional activator (STAT) signaling in the passive response but the aggressive behavior of RA-FLS is poorly understood. The pharmacologic effects of the novel JAK inhibitor, peficitinib, on cytokine-induced intracellular signaling and self-directed aggressive behavior of RA-FLS (e.g., increased expression of apoptosis-resistant genes and sodium nitroprusside-induced apoptosis) were investigated and compared with approved JAK inhibitors. RA-FLS assembly to form a lining-like structure and pro-inflammatory mediator production was investigated in three-dimensional (3D)-micromass culture. Peficitinib inhibited STAT3 phosphorylation in RA-FLS following induction by interferon (IFN)-α2b, IFN-γ, interleukin (IL)-6, oncostatin M, and leukemia inhibitory factor in a concentration-related manner, and was comparable to approved JAK inhibitors, tofacitinib and baricitinib. Peficitinib and tofacitinib suppressed autocrine phosphorylation of STAT3 and expression of apoptosis-resistant genes, and promoted cell death. In 3D-micromass culture, peficitinib reduced multi-layered RA-FLS cells to a thin monolayer, an effect less pronounced with tofacitinib. Both compounds attenuated production of vascular endothelial growth factor-A, matrix metalloproteinases, IL-6 and tumor necrosis factor superfamily-11. This study confirmed the pathogenic role of uncontrolled JAK-STAT signaling in the aggressive and passive responses of RA-FLS that are critical for RA progression. The novel JAK inhibitor peficitinib suppressed the pro-inflammatory behavior of RA-FLS, accelerated cell death and abrogated thickening of the synovium

High Performance of <i>N</i>-Alkoxycarbonyl-imines in Triethylborane-Mediated Tin-Free Radical Addition

Triethylborane-mediated tin-free radical alkylation of <i>N-</i>alkoxycarbonyl-imines, such as <i>N-</i>Boc-, <i>N-</i>Cbz-, and <i>N-</i>Teoc-imines, proceeded smoothly at a low temperature (−78 to −20 °C) to give the corresponding adducts in high yield. Although the formation of isocyanate was the major unfavorable reaction at room temperature, a one-pot conversion of <i>N-</i>Boc-imine to <i>N</i>-ethoxycarbonyl-adduct was possible through the corresponding isocyanate generated in situ. The higher performance of <i>N-</i>alkoxycarbonyl-imine than those of <i>N</i>-Ts- and <i>N</i>-PMP-imines is rationalized by a moderate electron-withdrawing character of an alkoxycarbonyl group that makes both addition of alkyl radical and trapping of the resulting aminyl radical by triethylborane efficiently fast

Radical One-Pot α,β-Dual and β-Mono-Oxymethylation of Alkylidenemalonate

Dimethylzinc-mediated radical conjugate addition reaction of dimethyl alkylidenemalonates with iodomethyl pivalate gave a high yield of the α,β-dual oxymethylation product in one pot under air and the β-pivaloyloxymethylation product under argon