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There are few studies on the genetic changes of meniscus degeneration. We used anterior cruciate ligament resection of Wuzhishan pig to prepare a meniscus degeneration model, and applied gene chip technology to detect differentially expressed genes in degenerative meniscus tissue. Then we applied GO analysis, Pathway analysis, Core gene network analysis and Relevant miRNAs analysis to discover relevant regulatory networks of meniscus degeneration. As a result, we detected 893 differentially expressed genes, mainly involving hormone, apoptosis, inflammation and other mechanisms, and obtained MUC13, Inflammatory mediator regulation of TRP channels, MDFI, mir-335-5p and so on that may play a key role. In summary, we have established a reliable animal model of meniscus degeneration and found that meniscus degeneration involves several possible molecular mechanisms, which will provide molecular targets for further research of the disease in the future.

A decanuclear dysprosium phosphonate (I) undergoes two consecutive SC–SC transformations, associated with OFF–ON–OFF switching of its single-molecule-magnetism., {Dy5(EDDC)2(μ3-AcO)2(μ5-C15H11PO3)(μ4-C15H11PO3)(μ2-AcO)2(AcO)2(H2O)(CH3OH)2}2(μ4-C2O4)·xH2O (I), where H2EDDC is N′,N′′,E,N′,N′′,E-N′,N′′-(ethane-1,2-diylidene)dipyrazine-2-carbohydrazide and C15H11PO3H2 is 9-anthrylmethylphosphonic acid, is found to undergo two consecutive single-crystal-to-single-crystal transformations. The first is under UV irradiation (λ = 365 nm for 3 d in air) to {Dy5(EDDC)2(μ3-AcO)2(μ5-C15H11PO3)2(μ2-AcO)2(AcO)2(H2O)3}2(μ4-C2O4)·xH2O (I-UV) where the two CH3OH are replaced by two H2O and the second by annealing under N2 at 100 °C on a diffractometer or under Ar in a glovebox to {Dy5(EDDC)2(μ3-AcO)2(μ5-C15H11PO3)2(μ2-AcO)4(H2O)}2(μ4-C2O4) (I-A-N2 or I-A-Ar) where it has lost two H2O molecules. The second transformation is reversible by exposure to air at room temperature (I-A-N2-cool). While the overall structures are the same (retaining the space group P21/c), there is a considerable expansion of the unit cell from I (8171 Å3) to I-UV (8609 Å3) and I-A-N2 (8610 Å3) and the coordinations of the Dy atoms undergo major reconstructions. This is associated with switching the single-molecule-magnetism (SMM) from OFF for I to ON for I-UV and to OFF again for I-A-Ar in air. Such a switching mechanism associated with the retention of crystallinity is unique in the chemistry of dysprosium. The structure of the molecule is formed from two symmetry related pentamers joined by an oxalate. A related compound containing two isolated neutral pentamers {Dy5(EDDC)2(μ3-AcO)2(μ5-C15H11PO3)2(μ2-AcO)3(AcO)2(H2O)2}{Dy5(EDDC)2(μ3-AcO)2(μ5-C15H11PO3)(μ4-C15H11PO3)(μ2-AcO)3(AcO)2(CH3OH)2}·2CHCl3 (II) has also been isolated with closely related Dy coordination and it exhibits similar SMM behaviour in zero field.

A microporous Tm-MOF {[Tm2L2(ox)(H2O)2]·4H2O}n (Tm-MOF, L ​= ​2-(pyridin-4-yl)-2H-imidazole-4, 5-dicarboxylate dianion; ox ​= ​oxalate dianion) with hydrogen bonds between the guest water molecules and host framework has been obtained. The CV and AC impendence studies suggested there was remarkable proton conducting behavior within Tm-MOF crystals, which was influenced by external voltage. The proton conducting mechanism was explored through dynamic simulation calculation. It was suggested that proton transferred between L ligand and water molecules through hydrogen bonds. And L ligand can isomerize to excited state stimulated by external voltage, which was essential and ensured the continuity of proton transfer. This simulated proton conduction process was verified by the fact that the low proton conductivity at 0 ​V vs. Ag-AgCl increased dramatically while open-circuit voltage increased to 1.6 ​V vs. Ag-AgCl. The UV absorption peak red shifting under higher voltage and the Ea value of 0.22eV lower than 0.4eV also confirmed the result of dynamic simulation.

Injectable three-dimensional (3D) scaffolds have the advantages of fluidity and moldability to fill irregular-shaped defects, simple incorporation of bioactive factors, and limited surgical invasiveness. Adipose-derived stem cells (ADSCs) are multipotent and can be differentiated toward nucleus pulposus (NP)-like cells. A hypoxic environment may be important for differentiation to NP-like cells because the intervertebral disc is an avascular tissue. Hence, we investigated the induction effects of hypoxia and an injectable 3D chitosan-alginate (C/A) gel scaffold on ADSCs.The C/A gel scaffold consisted of medical-grade chitosan and alginate. Gel porosity was calculated by liquid displacement method. Pore microstructure was analyzed by light and scanning electron microscopy. ADSCs were isolated and cultured by conventional methods. Passage 2 BrdU-labeled ADSCs were co-cultured with the C/A gel. ADSCs were divided into three groups (control, normoxia-induced, and hypoxia-induced groups). In the control group, cells were cultured in 10% FBS/DMEM. Hypoxia-induced and normoxia-induced groups were induced by adding transforming growth factor-β1, dexamethasone, vitamin C, sodium pyruvate, proline, bone morphogenetic protein-7, and 1% ITS-plus to the culture medium and maintaining in 2% and 20% O2, respectively. Histological and morphological changes were observed by light and electron microscopy. ADSCs were characterized by flow cytometry. Cell viability was investigated by BrdU incorporation. Proteoglycan and type II collagen were measured by safranin O staining and the Sircol method, respectively. mRNA expression of hypoxia-inducing factor-1α (HIF-1α), aggrecan, and Type II collagen was determined by reverse transcription-polymerase chain reaction.C/A gels had porous exterior surfaces with 80.57% porosity and 50-200 üm pore size. Flow cytometric analysis of passage 2 rabbit ADSCs showed high CD90 expression, while CD45 expression was very low. The morphology of induced ADSCs resembled that of NP cells. BrdU immunofluorescence showed that most ADSCs survived and proliferated in the C/A gel scaffold. Scanning electron microscopy showed that ADSCs grew well in the C/A gel scaffold. ADSCs in the C/A gel scaffold were positive for safranin O staining. Hypoxia-induced and normoxia-induced groups produced more proteoglycan and Type II collagen than the control group (P0.05). Proteoglycan and Type II collagen levels in the hypoxia-induced group were higher than those in the normoxia-induced group (P0.05). Compared with the control group, higher mRNA expression of HIF-1α, aggrecan, and Type II collagen was detected in hypoxia-induced and normoxiainduced groups (P0.05). Expression of these genes in the hypoxia-induced group was significantly higher than that in the normoxia-induced group (P0.05).ADSCs grow well in C/A gel scaffolds and differentiate toward NP-like cells that produce the same extracellular matrix as that of NP cells under certain induction conditions, which is promoted in a hypoxic state.