Nanofiber-induced hierarchically-porous magnesium phosphate bone cements accelerate bone regeneration by inhibiting Notch signaling.

Magnesium phosphate bone cements (MPC) have been recognized as a viable alternative for bone defect repair due to their high mechanical strength and biodegradability. However, their poor porosity and permeability limit osteogenic cell ingrowth and vascularization, which is critical for bone regeneration. In the current study, we constructed a novel hierarchically-porous magnesium phosphate bone cement by incorporating extracellular matrix (ECM)-mimicking electrospun silk fibroin (SF) nanofibers. The SF-embedded MPC (SM) exhibited a heterogeneous and hierarchical structure, which effectively facilitated the rapid infiltration of oxygen and nutrients as well as cell ingrowth. Besides, the SF fibers improved the mechanical properties of MPC and neutralized the highly alkaline environment caused by excess magnesium oxide. Bone marrow stem cells (BMSCs) adhered excellently on SM, as illustrated by formation of more pseudopodia. CCK8 assay showed that SM promoted early proliferation of BMSCs. Our study also verified that SM increased the expression of OPN, RUNX2 and BMP2, suggesting enhanced osteogenic differentiation of BMSCs. We screened for osteogenesis-related pathways, including FAK signaing, Wnt signaling and Notch signaling, and found that SM aided in the process of bone regeneration by suppressing the Notch signaling pathway, proved by the downregulation of NICD1, Hes1 and Hey2. In addition, using a bone defect model of rat calvaria, the study revealed that SM exhibited enhanced osteogenesis, bone ingrowth and vascularization compared with MPC alone. No adverse effect was found after implantation of SM in vivo. Overall, our novel SM exhibited promising prospects for the treatment of critical-sized bone defects.

Establishment of an immunogenic cell death-related model for prognostic prediction and identification of therapeutic targets in endometrial carcinoma.

OBJECTIVE: Studies have firmly established the pivotal role of the immunogenic cell death (ICD) in the development of tumors. This study seeks to develop a risk model related to ICD to predict the prognosis of patients with endometrial carcinoma (EC). MATERIALS AND METHODS: RNA-seq data of EC retrieved from TCGA database were analyzed using R software. We determined clusters based on ICD-related genes (ICDRGs) expression levels. Cox and LASSO analyses were further used to build the prediction model, and its accuracy was evaluated in the train and validation sets. Finally, in vitro and in vivo experiments were conducted to confirm the impact of the high-risk gene IFNA2 on EC. RESULTS: Patients were sorted into two ICD clusters, with survival analysis revealing divergent prognoses between the clusters. The Cox regression analysis identified prognostic risk genes, and the LASSO analysis constructed a model based on 9 of these genes. Notably, this model displayed excellent predictive accuracy when validated. Finally, increased IFNA2 levels led to decreased vitality, proliferation, and invasiveness in vitro. IFNA2 also has significant tumor inhibiting effect in vivo. CONCLUSIONS: The ICD-related model can accurately predict the prognosis of patients with EC, and IFNA2 may be a potential treatment target.

Preparation and application of UPLC silica microsphere stationary phase:A review.

In this review, microspheres for ultra-performance liquid chromatography (UPLC) were reviewed in accordance with the literature in recent years. As people's demands for chromatography are becoming more and more sophisticated, the preparation and application of UPLC stationary phases have become the focus of researchers in this field. This new analytical separation science not only maintains the practicality and principle of high-performance liquid chromatography (HPLC), but also improves the step function of chromatographic performance. The review presents the morphology of four types of sub-2 µm silica microspheres that have been used in UPLC, including non-porous silica microspheres (NPSMs), mesoporous silica microspheres (MPSMs), hollow silica microspheres (HSMs) and core-shell silica microspheres (CSSMs). The preparation, pore control and modification methods of different microspheres are introduced in the review, and then the applications of UPLC in drug analysis and separation, environmental monitoring, and separation of macromolecular proteins was presented. Finally, a brief overview of the existing challenges in the preparation of sub-2 µm microspheres, which required further research and development, was given.

PHRF1 promotes the class switch recombination of IgA in CH12F3-2A cells.

PHRF1 is an E3 ligase that promotes TGF-ß signaling by ubiquitinating a homeodomain repressor TG-interacting factor (TGIF). The suppression of PHRF1 activity by PML-RARα facilitates the progression of acute promyelocytic leukemia (APL). PHRF1 also contributes to non-homologous end-joining in response to DNA damage by linking H3K36me3 and NBS1 with DNA repair machinery. However, its role in class switch recombination (CSR) is not well understood. In this study, we report the importance of PHRF1 in IgA switching in CH12F3-2A cells and CD19-Cre mice. Our studies revealed that Crispr-Cas9 mediated PHRF1 knockout and shRNA-silenced CH12F3-2A cells reduced IgA production, as well as decreased the amounts of PARP1, NELF-A, and NELF-D. The introduction of PARP1 could partially restore IgA production in PHRF1 knockout cells. Intriguingly, IgA, as well as IgG1, IgG2a, and IgG3, switchings were not significantly decreased in PHRF1 deficient splenic B lymphocytes isolated from CD19-Cre mice. The levels of PARP1 and NELF-D were not decreased in PHRF1-depleted primary splenic B cells. Overall, our findings suggest that PHRF1 may modulate IgA switching in CH12F3-2A cells.

Plasmacytoid Dendritic Cells Enhance T-Independent B Cell Response through a p38 MAPK-STAT1 Axis.

TLR signaling in B cells triggers their activation and differentiation independent of help from T cells. Plasmacytoid dendritic cells (pDCs) cooperate with B cells to boost TLR-stimulated T-independent humoral immunity; however, the molecular mechanisms remain elusive. In this study, we demonstrate that in the mouse system, the adjuvant effects of pDCs also occurred following challenge with pathogens and that follicular (FO) B cells were more sensitive to pDC-induced enhancement than were marginal zone (MZ) B cells. Moreover, pDCs migrated to the FO zones and interacted with FO B cells upon stimulation in vivo. CXCL10, a ligand for CXCR3 expressed on pDCs, was superinduced in the coculture system and facilitated the cooperative activation of B cells. Moreover, pDCs also promoted TLR-stimulated autoantibody production in FO B and MZ B cells. Ingenuity Pathway Analysis and gene set enrichment analysis revealed that type I IFN (IFN-I)-mediated JAK-STAT and Ras-MAPK pathways were highly enriched in R848-stimulated B cells cocultured with pDCs compared with B cells alone. Whereas IFN-I receptor 1 deficiency reduced pDC-enhanced B cell responses, STAT1 deficiency displayed a more pronounced defect. One of the STAT1-dependent but IFN-I-independent mechanisms was TLR-induced STAT1-S727 phosphorylation by p38 MAPK. Serine 727 to alanine mutation attenuated the synergism between pDCs and B cells. In conclusion, we uncover a molecular mechanism for pDC-enhanced B cell response and define a crucial role of the IFN-I/TLR-mediated signaling pathway through a p38 MAPK-STAT1 axis in controlling T-independent humoral immunity and providing a novel therapeutic target for treating autoimmune diseases.

Regulation mechanism of plant response to heavy metal stress mediated by endophytic fungi.

Endophytic fungi exist widely in plants and play an important role in the growth and adaptation of plants. They could be used in phytoremediation techniques against heavy metal contaminated soil since beneficial microbial symbionts can endow plants with resistance to external heavy metal stresses. This review summarized the regulation mechanism of plant response to heavy metal stress mediated by endophytic fungi. Potential endophytic fungi in enhancing plant's adaption to heavy metal stresses include arbuscular mycorrhizal fungi, dark septate endophytic fungi, plant growth promoting endophytic fungi. The mechanisms involve coevolution strategy, immune regulation and detoxification transport to improve the ability of plants to adapt to heavy metal stress. They can increase the synthesis of host hormones and maintaining the balance of endogenous hormones, strengthen osmotic regulation, regulate carbon and nitrogen metabolism, and increase immune activity, antioxidant enzyme and glutathione activity. They also help to improve the detoxification transport and heavy metal emission capacity of the host by significantly producing iron carrier, metallothionein and 1-aminocyclopropane-1-carboxylic acid deaminase. The combination of endophytic fungi and hyperaccumulation plants provides a promising technology for the ecological restoration of heavy metal contaminated soil. Endophytic fungi reserves further development on enhancing host plant's adaptability to heavy metal stresses.

Phytoremediation is an effective method for ecological remediation of heavy metal contaminated soil. Endophytic fungi such as arbuscular mycorrhizal fungi, dark septate endophytic fungi, plant growth promoting endophytic fungi can synergistically improve the adaptability to heavy metal stress. This review comprehensively summarizes the regulation mechanism of plant response to heavy metal stress mediated by endophytic fungi for the first time, and provides new insights and proposals for exploring novel hyperaccumulator for phytoremediation more effectively. HIGHLIGHTSEndophytic fungi combined with phytoremediation could enhance plant's adaptition to heavy metal stress and ecological restoration efficiency.Promising endophytic fungi in improving phytoremediation for heavy metal contaminated soil are presented.The regulation mechanism of plant response to heavy metal stress mediated by endophytic fungi is firstly summarized.

A Biocompatible Self-Powered Piezoelectric Poly(vinyl alcohol)-Based Hydrogel for Diabetic Wound Repair.

Acute and chronic wounds, caused by trauma, tumors, diabetic foot ulcers, etc., are usually difficult to heal, while applying exogenous electrical stimulation to enhance the endogenous electric field in the wound has been proven to significantly accelerate wound healing. However, traditional electrical stimulation devices require an additional external power supply, making them poor in portability and comfort. In this work, a self-powered piezoelectric poly(vinyl alcohol) (PVA)/polyvinylidene fluoride (PVDF) composite hydrogel is constructed by establishing a distinctive preparation process of freezing/thawing-solvent replacement-annealing-swelling. The hydrogen bonding in the hydrogel is remarkably enhanced by the annealing-swelling process, which is stronger between PVA/PVDF molecules than that between PVA molecules, promoting transformation of the α-phase into the electroactive ß-phase PVDF and facilitating formation of a much more crystalline structure with high cross-linking density. Hence, an obvious piezoelectric response with high piezoelectric coefficient and electrical signal output with superior stability and sensitivity and excellent mechanical strength and stretchability was achieved for hydrogels. PVA/PVDF composite hydrogels with good cytocompatibility significantly promote proliferation, migration, and secretion of extracellular matrix proteins and growth factors of fibroblasts, possibly through activating the AKT and ERK1/2 signaling pathways. In a wound model of diabetic rats, piezoelectric hydrogels could not only rapidly attract wound exudate and maintain the wet environment of the wound bed but also convert the mechanical energy generated by rats' physical activities into electrical energy, so as to provide local piezoelectric stimulation to the wound bed evenly and symmetrically in real time. Such an effect significantly promotes re-epithelialization and collagen deposition and increases angiogenesis and secretion of growth factors in wound tissue. Besides, it regulates the macrophage phenotype from the M1 subtype (pro-inflammatory subtype) to the M2 subtype (anti-inflammatory subtype) and reduces the expression levels of inflammatory factors, thus accelerating wound healing. The development of such a novel piezoelectric hydrogel provides new therapeutic strategies for chronic wound healing.

3D printing of a poly(vinyl alcohol)-based nano-composite hydrogel as an artificial cartilage replacement and the improvement mechanism of printing accuracy.

Inspired by the gradient structure of articular cartilage, a poly(vinyl alcohol) (PVA)-based composite hydrogel with a biomimetic gradient structure as an artificial cartilage replacement was constructed by an extrusion 3D printing technique. The influence of the concentration and composition of the PVA-based solution on its rheological behavior and printability was studied, and the improvement mechanism for the 3D printing accuracy of the hydrogel was explored: introduction of GO or GO-HA gave rise to weakened inter-molecular hydrogen bonds and reduced entanglement density simultaneously, and the dynamic viscosity was highly improved. Therefore, the solution exhibited enhanced shear-thinning behavior in the printing shear rate range and a reduced Barus effect, thus highly improving the printability and printing accuracy of the samples. The 3D printing of PVA hydrogels was successfully achieved, and the printed biomimetic gradient samples possessed suitable compressive and tribological properties, which showed promising potential in the precise customized repair of artificial cartilage.

Insight into molecular information of Huolinguole lignite obtained by Fourier transform ion cyclotron resonance mass spectrometry and statistical methods.

RATIONALE: Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was applied to the characterization of organic compounds in coal extracts at the molecular level. Large volumes of data obtained by FT-ICR MS were processed via statistical methods to extract valuable information on the molecular structures and compositions of organic compounds in coal. METHODS: A low-rank coal was subjected to ultrasonic extraction sequentially with six solvents to separate and enrich species with different molecular characteristics. Complex mass spectra of the six extracts were obtained by a FT-ICR MS system equipped with two ionization sources. Two multivariate statistical methods, hierarchical clustering analysis (HCA) and principle component analysis (PCA), were introduced to mine useful information from the complex MS data and visually exhibit comprehensive molecular details in coal extracts. RESULTS: Similarities and differences between the 17 MS data sets from six coal extracts ionized by different ion sources were visually exhibited in plots via data processing using HCA and PCA. For HCA, all of the identified compounds were divided into seven classes (CH, O, N, S, ON, OS, and NS), and detailed differences in the relative abundance were revealed. In addition, PCA discriminated the differences in molecular composition for organic compounds from the six extracts. CONCLUSIONS: Multivariate statistical analysis is a promising methodology which can interpret the chemical composition of coals and coal derivatives at the molecular level, especially for the analysis of multiple complex samples presenting in a single plot.

Analysis of soluble components in coals and interpretations for the complex mass spectra.

RATIONALE: The deduction of useful information from the mass spectra of a complex mixture like coals remains difficult, which limits the clean and efficient utilization of coals. It is necessary to explore the data interpretation methods for mass spectra and visualize the analytical data of coals for industrial utilization such as feedstock selection. METHODS: Coal sample and methanol were mixed and heated to 310 °C and kept at that temperature for 2 h. The solvent was under supercritical state at 310 °C and the solubility for the solid mixture increased. Soluble products from thermal dissolution of two Chinese coals were analyzed by high-performance liquid chromatography/atmospheric pressure chemical ionization orbitrap mass spectrometry. RESULTS: The iso-abundance plot for molecules in coals was upgraded to display the distributions of isomers which are indicated as concentric circles or triangles with the same carbon number and value of double-bond equivalent. The concentration ratio was introduced from economics to describe the content inequality of organic species within the same class of coal molecules. CONCLUSIONS: Interpretation methods for mass spectra visualize and simplify the understanding of complex components in coals for industrial utilization. Coals with a high concentration ratio for a specific class should take priority as a feedstock for chemicals and receive more attention. Copyright © 2016 John Wiley & Sons, Ltd.