Recently, materials with controlled oil/water separation ability became a new research focus. Herein, we report a novel copper mesh film, which is superhydrophobic and superhydrophilic for nonalkaline water and alkaline water, respectively. Meanwhile, the film shows superoleophobicity in alkaline water. Using the film as a separating membrane, the oil/water separating process can be triggered on-demand by changing the water pH, which shows a good controllability. Moreover, it is found that the nanostructure and the appropriate pore size of the substrate are important for realization of a good separation effect. This paper offers a new insight into the application of surfaces with switchable wettability, and the film reported here has such a special ability that allows it to be used in other applications, such as sewage purification, filtration, and microfluidic device.

microRNAs could be mechanosensitive and emerge as critical posttranscriptional regulators in the bone-remodeling process. During orthodontic tooth movement (OTM), the application of mechanical force induces alveolar bone remodeling, but whether microRNAs respond to orthodontic force and contribute to OTM is unknown. microRNA-21 (miR-21) has been previously reported in vitro to mediate stretch-induced osteogenic differentiation of periodontal ligament stem cells and support osteoclast differentiation. In this study, the authors show that miR-21 responded to orthodontic force in periodontal tissue in a dose- and time-dependent manner and regulated the osteogenesis of human periodontal ligament stem cells following OTM. Using mmu-miR-21-deficient (miR-21) mice, the authors discovered that mmu-miR-21 deficiency inhibited OTM and prevented force-induced maxillary bone loss. The authors found that miR-21 mice showed a normal skeletal phenotype in development and a similar alveolar bone formation rate to wild-type mice postnatally. During OTM, mmu-miR-21 regulated force-induced alveolar osteoblastogenesis in the tensile side, while no effects were detected in the compressive side. However, miR-21 mice showed inhibited alveolar osteoclastogenesis when compared with wild-type mice. During OTM, mmu-miR-21 deficiency blocked alveolar bone resorption in both the compressive and tensile sides. To dissect the mechanism by which miR-21 regulates alveolar bone remodeling, the authors screened the reported functional targets of miR-21 and found that periodontal expression of programmed cell death 4 ( Pdcd4) was inhibited following OTM. Furthermore, mmu-miR-21 deficiency removed the suppression of Pdcd4 at both the mRNA and protein levels in the periodontium, resulting in upregulation of the downstream effector C-fos. Further analysis of OTM under lipopolysaccharide-induced periodontal inflammation showed that mmu-miR-21 mediated lipopolysaccharide (LPS)-accelerated OTM and that mmu-miR-21 deficiency blocked lipopolysaccharide-induced maxillary bone loss. In summary, these findings reveal a previously unrecognized mechanism that a microRNA can modulate OTM and alveolar bone remodeling under both normal and inflammatory microenvironments in vivo.

Surfaces with controlled oil wettability in water have great potential for numerous underwater applications. In this work, we report a smart surface with pH-responsive oil wettability. The surface shows superoleophilicity in acidic water and superoleophobicity in basic water. Reversible transition between the two states can be achieved through alteration of the water pH. Such smart ability of the surface is due to the cooperation between the surface chemistry variation and hierarchical structures on the surface. Furthermore, we also extended this strategy to the copper mesh substrate and realized the selective oil/water separation on the as-prepared film. This paper reports a new surface with excellently controllable underwater oil wettability, and we believe such a surface has a lot of applications, for instance, microfluidic devices, bioadhesion, and antifouling materials.

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Surfaces with controlled underwater oil wettability would offer great promise in the design and fabrication of novel materials for advanced applications. Herein, we propose a new approach based on self-assembly of mixed thiols (containing both HS(CH2)9CH3 and HS(CH2)11OH) on nanostructured copper substrates for the fabrication of surfaces with controlled underwater oil wettability. By simply changing the concentration of HS(CH2)11OH in the solution, surfaces with controlled oil wettability from the underwater superoleophilicity to superoleophobicity can be achieved. The tunable effect can be due to the synergistic effect of the surface chemistry variation and the nanostructures on the surfaces. Noticeably, the amplified effect of the nanostructures can provide better control of the underwater oil wettability between the two extremes: superoleophilicity and superoleophobicity. Moreover, we also extended the strategy to the copper mesh substrates and realized the selective oil/water separation on the as-prepared copper mesh films. This report offers a flexible approach of fabricating surfaces with controlled oil wettability, which can be further applied to other ordinary materials, and open up new perspectives in manipulation of the surface oil wettability in water.

The association between inflammation and endoplasmic reticulum (ER) stress has been described in many diseases. However, if and how chronic inflammation governs the unfolded protein response (UPR) and promotes ER homeostasis of chronic inflammatory disease remains elusive. In this study, chronic inflammation resulted in ER stress in mesenchymal stem cells in the setting of periodontitis. Long-term proinflammatory cytokines induced prolonged ER stress and decreased the osteogenic differentiation of periodontal ligament stem cells (PDLSCs). Interestingly, we showed that chronic inflammation decreases the expression of lysine acetyltransferase 6B (KAT6B, also called MORF), a histone acetyltransferase, and causes the upregulation of a key UPR sensor, PERK, which lead to the persistent activation of the UPR in PDLSCs. Furthermore, we found that the activation of UPR mediated by MORF in chronic inflammation contributes to the PERK-related deterioration of the osteogenic differentiation of PDLSCs both in vivo and in vitro. Taken together, our results suggest that chronic inflammation compromises UPR function through MORF-mediated-PERK transcription, which is a previously unrecognized mechanism that contributes to impaired ER function, prolonged ER stress and defective osteogenic differentiation of PDLSCs in periodontitis. Cell Death and Differentiation (2016) 23, 1862-1872 doi:10.1038/cdd.2016; published online 22 July 2016The endoplasmic reticulum (ER) primarily functions in protein biosynthesis and folding, lipid trafficking, metabolism and intracellular calcium storage. Elevated physiological demand for protein folding can cause the accumulation of misfolded or unfolded proteins in the ER lumen, a state called ER stress.

Tissue engineered bone has become a bone substitute for the treatment of bone defects in animal research. This study investigated the osteogenesis capacity of coralMSCs-rhBMP-2 composite with the auto-bone-graft as control. Coral-MSCs-rhBMP-2 composite were fabricated by coral (as main scaffold), rhBMP-2 (as growth factor), and MSCs (cultured from iliac marrow as seed cells). Criticalsized defects (d ¼ 15 mm) were made on forty rabbits crania and treated by different composite scaffolds: iliac autograft (n ¼ 8), coral (n ¼ 8), rhBMP-2/coral (n ¼ 8), and MSCs/rhBMP-2/coral (n ¼ 8). The defects were evaluated by gross observation, radiographic examination, histological examination, and histological fluorescence examinations after 8 and 16 weeks. The results showed that repair of bone defect was the least in coral group, and significant ingrowth of new bone formation and incorporation could be seen with 77.45% 6 0.52% in radiopacity in MSCs/ rhBMP-2/coral group, which was similar to that in iliac autograft group (84.61% 6 0.56% in radiopacity). New bone formation in MSCs/rhBMP-2/coral group was more than that in rhBMP-2/coral group. And osteogenesis rate in MSCs/rhBMP-2/coral group (10.23 6 1.45 mm) was much faster than that in rhBMP-2/coral group (5.85 6 2.19 mm) according to histological fluorescence examination. Newly formed bone partly came from induced MSCs in composite scaffold according to bromodeoxyuridine immunohistochemical examination. These data implicated that MSCs could produce synergic effect with coral-rhBMP-2, and the tissue engineered bone of coral-MSCs-rhBMP-2 is comparable to auto-bone-graft for the repair of critical-sized bone defect.

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