Highly Tunable Charge-Spin Conversion in Topological Insulator Cr0.08-(Bi0.37Sb0.63)1.92Te3 via Ferroelectric Polarization.

Topological insulators possess strong spin-orbit coupling, which potentially presents efficient charge-spin interconversion. The effective manipulation of this conversion plays a central role in spin-based device applications and is attracting increasing attention nowadays. In this study, by constructing a multifunctional hybrid device Cr-BST/Py/PMN-PT and applying spin-torque ferromagnetic resonance measurement, continuously controllable charge-spin conversion efficiency and even the enhancement of its value up to about 450% are realized via regulation of the ferroelectric polarization in the topological insulator Cr-BST. The band structure of Cr-BST characterized by angle-resolved photoelectron spectroscopy measurement presents an apparent Dirac-like state located at the large band gap of the bulk state near the Fermi level, which indicates a surface state-dominated contribution to the charge-spin conversion. Further investigation via density functional theory on the electronic structure of BST verifies that the controllable conversion efficiency dominantly originates from the evolution of the band structure under strain modulation. These findings demonstrate TIs as one of the promising materials for the charge-spin interconversion and its regulation, which are instructive for low-dissipation spintronics devices.

Schwann Cells Accelerate Osteogenesis via the Mif/CD74/FOXO1 Signaling Pathway In Vitro.

Schwann cells have been found to promote osteogenesis by an unclear molecular mechanism. To better understand how Schwann cells accelerate osteogenesis, RNA-Seq and LC-MS/MS were utilized to explore the transcriptomic and metabolic response of MC3T3-E1 to Schwann cells. Osteogenic differentiation was determined by ALP staining. Lentiviruses were constructed to alter the expression of Mif (macrophage migration inhibitory factor) in Schwann cells. Western blot (WB) analysis was employed to detect the protein expression. The results of this study show that Mif is essential for Schwann cells to promote osteogenesis, and its downstream CD74/FOXO1 is also involved in the promotion of Schwann cells on osteogenesis. Further, Schwann cells regulate amino acid metabolism and lipid metabolism in preosteoblasts. These findings unveil the mechanism for Schwann cells to promote osteogenesis where Mif is a key factor.

Role of psoriatic keratinocytes in the metabolic reprogramming of dermal mesenchymal stem cells.

BACKGROUND: Psoriasis is an immune-mediated inflammatory skin disease, featured by epidermal hyperproliferation. Psoriasis exhibits metabolic abnormalities, which can further aggravate the condition of psoriasis. The present study aimed to investigate the role of psoriatic keratinocytes (KCs) in the metabolic reprogramming of dermal mesenchymal stem cells (DMSCs). METHODS: Dermal mesenchymal stem cells were cocultured with primary KCs either from psoriatic lesions or from normal subjects using Transwell plate. Glycolysis and mitochondrial metabolism of DMSCs were detected by Seahorse Metabolic Analyzer. Expression levels of proteins were analyzed by Western blotting. DMSCs proliferation was assessed using 5-ethynyl-2'-deoxyuridine assay and Cell Counting Kit-8. RESULTS: In comparison with normal KCs, coculture of psoriatic KCs with DMSCs dramatically increased glycolytic and mitochondrial metabolism, and expression levels of stem cell factor, epidermal growth factor, glucose transporter 1, and c-Myc. Moreover, psoriatic KCs were more potent than normal KCs in the stimulation of DMSC proliferation. CONCLUSIONS: In conclusion, psoriatic KCs display a higher potency in metabolic reprogramming and stimulation of DMSC proliferation, possibly contributing to the pathogenesis of psoriasis. However, whether the intervention of metabolic reprogramming of DMSCs can alleviate psoriasis remains to be determined.

The effect of fluid shear stress on fibroblasts and stem cells on plane and groove topographies.

In this study, we aimed to study the effect of fluid shear stress on fibroblasts and BMSCs on plane and groove topographies. The results showed that 0.6-Hz stress had the greatest influence on the alignment, polarity, migration and adhesion of fibroblasts on plane by increasing the expression of reoriented actin and vinculin; whereas 1.0-Hz stress promoted differentiation of fibroblasts into myofibroblasts by increasing Col-I and α-SMA expression. Interestingly, under the given frequency stress, the groove structure strengthened the above characteristics of fibroblasts beyond adhesion, and promoted differentiation of BMSCs into myofibroblasts. The above results indicate that 0.6 Hz may improve the implant-tissue sealing, while 1.0-Hz stress probably causes the disordered fiber deposition around implants.

Effects of cyclic fluid stress at different frequencies on behaviors of cells incubated on titanium alloy.

The orthopedic external fixation is always in dynamic mechanical environment with the somatic movement. We used a self-designed mini oscillator to simulate this condition by providing the reciprocating cyclic fluid stress, and observed the behavioral responses of fibroblasts implanted on titanium alloy plane to the stress at different frequencies, including 0.2 Hz, 0.6 Hz, and 1.0 Hz. We found that the cell angle, shape index and expression of vinculin were mostly biphasic-dependent with the increase of frequency, with peaks at 0.6 Hz. Whereas the cell area, expression of Col-I and α-SMA were mainly affected by the 1.0 Hz stress. Interestingly, 1.0 Hz stress also promoted Col-I expression of bone marrow mesenchymal stem cells (BMSCs), although it did not increase α-SMA. These results reveal that 0.6 Hz stress improves the alignment, polarity and adherence of fibroblasts on titanium alloy substrates, thus improving the sealing of implants; the 1.0 Hz force activates the differentiation of fibroblasts into myofibroblasts and increases collagen produced by stem cells, which probably cause the formation of fibrous capsules around implants.

Co-Delivery of Curcumin and Paclitaxel by "Core-Shell" Targeting Amphiphilic Copolymer to Reverse Resistance in the Treatment of Ovarian Cancer.

BACKGROUND: Ovarian cancer is a common malignancy in the female reproductive system with a high mortality rate. The most important reason is multidrug resistance (MDR) of cancer chemotherapy. To reduce side effects, reverse resistance and improve efficacy for the treatment of ovarian cancer, a "core-shell" polymeric nanoparticle-mediated curcumin and paclitaxel co-delivery platform was designed. METHODS: Nuclear magnetic resonance confirmed the successful grafting of polyethylenimine (PEI) and stearic acid (SA) (PEI-SA), which is designed as a mother core for transport carrier. Then, PEI-SA was modified with hyaluronic acid (HA) and physicochemical properties were examined. To understand the regulatory mechanism of resistance and measure the anti-tumor efficacy of the treatments, cytotoxicity assay, cellular uptake, P-glycoprotein (P-gp) expression and migration experiment of ovarian cancer cells were performed. In addition, adverse reactions of nanoformulation to the reproductive system were examined. RESULTS: HA-modified drug-loaded PEI-SA had a narrow size of about 189 nm in diameters, and the particle size was suitable for endocytosis. The nanocarrier could target specifically to CD44 receptor on the ovarian cancer cell membrane. Co-delivery of curcumin and paclitaxel by the nanocarriers exerts synergistic anti-ovarian cancer effects on chemosensitive human ovarian cancer cells (SKOV3) and multi-drug resistant variant (SKOV3-TR30) in vitro, and it also shows a good anti-tumor effect in ovarian tumor-bearing nude mice. The mechanism of reversing drug resistance may be that the nanoparticles inhibit the efflux of P-gp, inhibit the migration of tumor cells, and curcumin synergistically reverses the resistance of PTX to increase antitumor activity. It is worth noting that the treatment did not cause significant toxicity to the uterus and ovaries with the observation of macroscopic and microscopic. CONCLUSION: This special structure of targeting nanoparticles co-delivery with the curcumin and paclitaxel can increase the anti-tumor efficacy without increasing the adverse reactions as a promising strategy for therapy ovarian cancer.

Low-Temperature Additive Manufacturing of Biomimic Three-Dimensional Hydroxyapatite/Collagen Scaffolds for Bone Regeneration.

Low-temperature additive manufacturing (AM) holds promise for fabrication of three-dimensional (3D) scaffolds containing bioactive molecules and/or drugs. Due to the strict technical limitations of current approaches, few materials are suitable for printing at low temperature. Here, a low-temperature robocasting method was employed to print biomimic 3D scaffolds for bone regeneration using a routine collagen-hydroxyapatite (CHA) composite material, which is too viscous to be printed via normal 3D printing methods at low temperature. The CHA scaffolds had excellent 3D structure and maintained most raw material properties after printing. Compared to nonprinted scaffolds, printed scaffolds promoted bone marrow stromal cell proliferation and improved osteogenic outcome in vitro. In a rabbit femoral condyle defect model, the interconnecting pores within the printed scaffolds facilitated cell penetration and mineralization before the scaffolds degraded and enhanced repair, compared to nonprinted CHA scaffolds. Additionally, the optimal printing parameters for 3D CHA scaffolds were investigated; 600-µm-diameter rods were optimal in terms of moderate mechanical strength and better repair outcome in vivo. This low-temperature robocasting method could enable a variety of bioactive molecules to be incorporated into printed CHA materials and provides a method of bioprinting biomaterials without compromising their natural properties.

Mechanism of fatty acid synthase in drug tolerance related to epithelial-mesenchymal transition of breast cancer.

OBJECTIVE: The mechanism of action of fatty acid synthase (FASN) in drug tolerance of breast cancer cells with epithelial-mesenchymal transition (EMT) features was investigated. METHODS: The breast cancer cell line MCF-7-MEK5 with stably occurring EMT and tumour necrosis factor-α (TNF-α) tolerance was used as the experimental model, whereas MCF-7 acted as the control. Tumour cells were implanted into nude mice for in vivo analysis, and cerulenin was used as a FASN inhibitor. RT-PCR, real-time quantitative PCR and Western blot were employed to detect the expression of FASN, TNFR-1, TNFR-2, Wnt-1, ß-catenin and cytC at the RNA and protein levels. RESULTS: Compared with MCF-7, TNFR-1 expression in MCF-7-MEK5 was slightly changed, TNFR-2 was decreased, and FASN, Wnt-1, ß-catenin and cytC were increased. The expression of Wnt-1 and ß-catenin in MCF-7-MEK5 decreased after cerulenin treatment, whereas cytC expression increased. CONCLUSIONS: The important function of FASN in the drug tolerance of breast cancer may be due to the following mechanisms: FASN downregulated TNFR-2 expression through lipid rafts to make the cells less sensitive to TNF-α, and simultaneously activated the Wnt-1/ß-catenin signalling pathway. Thus, cytC expression increased, which provided cells with anti-apoptotic capacity and induced drug tolerance.

Therapeutic effectiveness of intravenous immunoglobulin at 1 g/kg and 2 g/kg on Kawasaki disease: a comparative and follow-up study / 中华儿科杂志

<p><b>OBJECTIVE</b>To evaluate the effectiveness of intravenous immunoglobulin IVIG, 1 g/kg single intravenous injection in treating and preventing cardiac consequences of Kawasaki disease (KD) in children.</p><p><b>METHODS</b>A total of 242 children with KD disease were enrolled in the study. In the randomized controlled trial, they were randomly divided into two groups: IVIG 1 g/kg group and IVIG 2 g/kg group, with aspirin administered within the first 7 to 10 days of illness. The occurrence and restoration of coronary artery lesion (CAL) in these two groups as well as the clinical and laboratory indexes including total fever duration, restoration of cervical lymphadenopathy, white blood cells count, platelet count, serum immunoglobulin, C reactive protein, erythrocyte sedimentation rate and EKG were observed. The clinical effectiveness of the groups before and after the treatment was analyzed.</p><p><b>RESULTS</b>The age of the 242 children with KD disease ranged from 3 months to 14 years (mean 4.0 +/- 2.8 years old). Male to female ratio was 1.66:1, 83.1% of KD patients were blow 5 years old, 93.4% patients were followed up with echocardiography at the end of the first year and the follow-up period was (38 +/- 18) months, ranging from 4 months to 5.4 years; 86.9% of the cases in 1 g/kg group and 91.7% of the cases in 2 g/kg group had their fever controlled within 48 hours. The difference was not significant (P > 0.05). Serum immunoglobulin level was markedly enhanced after IVIG. Serum immunoglobulin levels in the patients of 2 g/kg group and 1 g/kg group were (26.9 +/- 7.4) g/L and (18.3 +/- 6.9) g/L, respectively (P < 0.01). The average duration of fever in IVIG 1 g/kg group was 10.6 days. After the treatment with 1 g/kg of IVIG, the abnormal white blood cells count, platelet count, C reactive protein, erythrocyte sedimentation rate and abnormal EKG findings were greatly improved (P < 0.001). However, there was no significant difference in the above-mentioned improvement between IVIG 1 g/kg group and IVIG 2 g/kg group (P > 0.05). In IVIG 1 g/kg group the occurrence of CAL was 29.5%. After the one-year follow-up, 87.5% CAL restored, but 12.5% did not, among which 9.4% were those of IVIG non-responders. In IVIG 2 g/kg group the incidence of CAL was 24.2%. After the one-year follow-up, 89.3% CAL restored, but 10.7% did not, all of which were those of IVIG non-responders. There was no significant difference in the incidence of CAL between the two groups (P > 0.05).</p><p><b>CONCLUSION</b>Single intravenous injection of IVIG at 1 g/kg could effectively alleviate the clinical symptoms, decrease the incidence of CAL and reduce the complication of cardiovascular system. In the treatment of KD, the therapeutic effectiveness of IVIG at 1 g/kg was not significantly different from that of single intravenous injection of IVIG at 2 g/kg.</p>