Room-temperature ferromagnetism in epitaxial bilayer FeSb/SrTiO3(001) terminated with a Kagome lattice

Two-dimensional (2D) magnets exhibit unique physical properties for potential applications in spintronics. To date, most 2D ferromagnets are obtained by mechanical exfoliation of bulk materials with van der Waals interlayer interactions, and the synthesis of single or few-layer 2D ferromagnets with strong interlayer coupling remains experimentally challenging. Here, we report the epitaxial growth of 2D non-van der Waals ferromagnetic bilayer FeSb on SrTiO3(001) substrates stabilized by strong coupling to the substrate, which exhibits in-plane magnetic anisotropy and a Curie temperature above 300 K. In-situ low-temperature scanning tunneling microscopy/spectroscopy and density-functional theory calculations further reveal that a Fe Kagome layer terminates the bilayer FeSb. Our results open a new avenue for further exploring emergent quantum phenomena from the interplay of ferromagnetism and topology for application in spintronics

Synovial Macrophages: Past Life, Current Situation, and Application in Inflammatory Arthritis

Inflammatory arthritis is an inflammatory disease that involves the joints and surrounding tissues. Synovial hyperplasia often presents when joints become inflamed due to immune cell infiltration. Synovial membrane is an important as well as a highly specific component of the joint, and its lesions can lead to degeneration of the joint surface, causing pain and joint disability or affecting the patients’ quality of life in severe cases. Synovial macrophages (SMs) are one of the cellular components of the synovial membrane, which not only retain the function of macrophages to engulf foreign bodies in the joint cavity, but also interact with synovial fibroblasts (SFs), T cells, B cells, and other inflammatory cells to promote the production of a variety of pro-inflammatory cytokines and chemokines, such as TNF-α, IL-1β, IL-8, and IL-6, which are involved in the pathogenic process of inflammatory arthritis. SMs from different tissue sources have differently differentiated potentials and functional expressions. This article provides a summary on studies pertaining to SMs in inflammatory arthritis, and explores their role in its treatment, in order to highlight novel treatment modalities for the disease

Calcium Homeostasis in Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes

Rationale: Cardiomyocytes generated from human induced pluripotent stem cells (hiPSCs) are suggested as the most promising candidate to replenish cardiomyocyte loss in regenerative medicine. Little is known about their calcium homeostasis, the key process underlying excitation-contraction coupling. Objective: We investigated the calcium handling properties of hiPSC-derived cardiomyocytes and compared with those from human embryonic stem cells (hESCs). Methods and Results: We differentiated cardiomyocytes from hiPSCs (IMR90 and KS1) and hESCs (H7 and HES3) with established protocols. Beating outgrowths from embryoid bodies were typically observed 2 weeks after induction. Cells in these outgrowths were stained positively for tropomyosin and sarcomeric alpha-actinin. Reverse-transcription polymerase chain reaction studies demonstrated the expressions of cardiac-specific markers in both hiPSC- and hESC-derived cardiomyocytes. Calcium handling properties of 20-day-old hiPSC- and hESC-derived cardiomyocytes were investigated using fluorescence confocal microscopy. Compared with hESC-derived cardiomyocytes, spontaneous calcium transients from both lines of hiPSC-derived cardiomyocytes were of significantly smaller amplitude and with slower maximal upstroke velocity. Better caffeine-induced calcium handling kinetics in hESC-CMs indicates a higher sacroplasmic recticulum calcium store. Furthermore, in contrast with hESC-derived cardiomyocytes, ryanodine did not reduce the amplitudes, maximal upstroke and decay velocity of calcium transients of hiPSC-derived cardiomyocytes. In addition, spatial inhomogeneity in temporal properties of calcium transients across the width of cardiomyocytes was more pronounced in hiPSC-derived cardiomyocytes than their hESC counterpart as revealed line-scan calcium imaging. Expressions of the key calcium-handling proteins including ryanodine recptor-2 (RyR2), sacroplasmic recticulum calcium-ATPase (SERCA), junction (Jun) and triadin (TRDN), were significantly lower in hiPSC than in hESCs. Conclusions: The results indicate the calcium handling properties of hiPSC-derived cardiomyocytes are relatively immature to hESC counterparts. © 2011 The Author(s).published_or_final_versionSpringer Open Choice, 21 Feb 201

Quantitative Analysis of Six Phenolic Acids in Artemisia capillaris (Yinchen) by HPLC-DAD and Their Transformation Pathways in Decoction Preparation Process

We aimed to establish a quantitative analysis method of six constituents (5-caffeoylquinic acid, 3-caffeoylquinic acid, 4-caffeoylquinic acid, 1,3-dicaffeoylquinic acid, 3,4-dicaffeoylquinic acid, and 4,5-dicaffeoylquinic acid) in Artemisia capillaris (Yinchen) and its decoction by using HPLC coupled with DAD. Besides, the transformation paths of the six constituents were analyzed in decoction preparation processing. The analytical method was fully validated in terms of linearity, sensitivity, precision, repeatability, and recovery and applied to assess the transformation trend and quantitative analysis of the six constituents in Yinchen decoction. The contents of six constituents varied greatly in Yinchen herb and Yinchen decoction, and there were inextricable internal relationships between them. Presumably 3-caffeoylquinic acid was isomerized to generate 5-caffeoylquinic acid and 4-caffeoylquinic acid. Similarly, 1,3-dicaffeoylquinic acid and 3,4-dicaffeoylquinic acid were produced by isomerization of 4,5-dicaffeoylquinic acid. In conclusion, this study provides a chemical basis for quality control of Yinchen decoction, and the changes of selected markers in decoction could give us some novel perspectives to study the relationship between substances and drug efficacy

Temperature-Dependent in Situ Reduction of 4,4′-Azobispyridine via Solvothermal Reaction

Solvothermal reactions of 2,2′-biphenyldicarboxylate (H₂dpa) and 4,4′-azobispyridine (azpy) in the presence of transition metal ions produce six new complexes, namely, [Co­(dpa)­(bphy)]_<i>n</i> (<b>1</b>), [Co­(dpa)­(azpy)­(H₂O)]_<i>n</i>·0.5<i>n</i>H₂O (<b>2</b>), [Zn­(dpa)­(bphy)]_<i>n</i> (<b>3</b>), [Zn­(dpa)­(azpy)­(H₂O)]_<i>n</i> (<b>4</b>), [Mn­(dpa)­(azpy)­(H₂O)]_<i>n</i>·0.5<i>n</i>H₂O (<b>5</b>), and [Mn­(dpa)­(azpy)]_<i>n</i>·<i>n</i>H₂O·<i>n</i>MeOH (<b>6</b>) (bphy = 1,2-bis­(4-pyridyl)­hydrazine). The crystal structure analyses reveal that complexes <b>1</b> and <b>3</b> are isostructural which features a plywood-like structure, while complex <b>4</b> exhibits a parallel chains array. Complexes <b>2</b> and <b>5</b> afford a two-dimensional chiral (4,4) network, and complex <b>6</b> shows a (4,4) network. It was noteworthy that the in situ reduction of azpy to bphy was found in complexes <b>1</b> and <b>3</b>, which were confirmed by single-crystal structures and LC-MS analyses. However, this in situ reduction was not found at a low reaction temperature in the syntheses of complexes <b>2</b>,<b> 4</b>, and <b>5</b>. The second-harmonic-generation (SHG) properties of <b>1</b> and <b>3</b> and the solid circular dichroism (CD) properties of <b>2</b> and <b>5</b> were investigated. In addition, luminescent properties of complexes <b>3</b> and <b>4</b> as well as magnetic properties of complexes <b>1</b>, <b>2</b>, <b>5</b>, and <b>6</b> were also studied