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Since several "red oil" explosion accidents have occurred in the spent fuel reprocessing process, which is mainly due to the mix of HNO3 and organic solvent at high temperature, the reaction between HNO3, TBP and n-dodecane at different conditions were studied to simulate the evaporation concentration process. The temperature and pressure changes were observed, and the main liquid and gas components were analyzed qualitatively and quantitatively by using FTIR and GC/MS. Furthermore, the reaction mechanism is also concluded. It is hope to provide some basic data to design the standards and safety limits in evaporation concentration process of spent fuel reprocessing. [ABSTRACT FROM AUTHOR]

Frozen shoulder is a common shoulder disorder characterized by a gradual increase of pain and a limited range of motion. However, its pathophysiologic mechanisms remain unclear and there is no consensus as to the most effective treatment. The purpose of the study was to investigate the effect of transforming growth factor‐β (TGF‐β) on fibrosis and inflammatory response of the shoulder joint of rat models and to explore the therapeutic effect of the peroxisome proliferator‐activated receptor‐γ (PPAR‐γ) agonist. In the study, the effect of PPAR‐γ agonist CDDO‐IM treatment on cell proliferation, migration, and extracellular matrix proteins synthesis (vimentin, α‐smooth muscle actin, collagen I, and collagen III) were tested by cell proliferation test, scratches test, real‐time quantitative polymerase chain reaction, and Western blot analysis. The frozen shoulder was also established on the rat model by injecting adenovirus‐TGF‐β1 into rats' shoulder capsule. Pathological changes of the frozen shoulder tissue of the experimental group and PPAR‐γ agonist treatment group were evaluated. The stiffness of joints of the three groups was tested. Inflammatory mediators' expression including cyclooxygenase‐1, interleukin‐1β, and tumor necrosis factor‐α of the shoulder was tested by enzyme‐linked immunosorbent assay, and the expression of extracellular matrix proteins was evaluated by hematoxylin and eosin staining and immunohistochemistry. The results showed that pathological changes of the frozen shoulder in the rat model include an abnormal proliferation of fibroblasts, infiltration of inflammatory cells, and disorder of fibrous structure, while rosiglitazone reduced the severity of the frozen shoulder in the treatment group. Clinically, PPAR‐γ agonists may be a promising target for the treatment of the frozen shoulder. [ABSTRACT FROM AUTHOR]

The article titled "Innenrücktitelbild: Nanosheet-Assembled Zirconium-Porphyrin Frameworks Enabling Surface-Confined, Initiator-Free Photosynthesis of Ultrahigh Molecular Weight Polymers" discusses the development of hierarchical metal-organic frameworks with low-dimensional architectures. The researchers, Yiyun Geng, Gang Ye, and others, have created nanosheet-assembled Zr-porphyrin frameworks that have the ability to harvest a broad range of photons and enhance photocatalytic activity. These frameworks enable the synthesis of ultrahigh molecular weight polymers through an initiator-free, visible-light-regulated radical polymerization process. The resulting polymers have a molecular weight greater than 1,500,000. [Extracted from the article]

Introduction: Currently, osteoarthritis (OA) receives global increasing attention because it associates severe joint pain and serious disability. Stem cells intra-articular injection therapy showed a potential therapeutic superiority to reduce OA development and to improve treating outputs. However, the long-term effect of stem cells intra-articular injection on the cartilage regeneration remains unclear. Recently, miR-140-5p was confirmed as a critical positive regulator in chondrogenesis. We hypothesized that hUC-MSCs overexpressing miR-140-5p have better therapeutic effect on osteoarthritis.Materials and Methods: To enhance stem cell chondrogenic differentiation, we have transfected human umbilical cord mesenchymal stem cells (hUC-MSCs) with miR-140-5p mimics and miR-140-5p lentivirus to overexpress miR-140-5p in a short term or a long term accordingly. Thereafter, MSCs proliferation, chondrogenic genes expression and extracellular matrix were assessed. Destabilization of the medial meniscus (DMM) surgery was performed on the knee joints of SD rats as an OA model, and then intra-articular injection of hUC-MSCs or hUC-MSCs transfected with miR-140-5p lentivirus was carried to evaluate the cartilage healing effect with histological staining and OARSI scores. The localization of hUC-MSCs after intra-articular injection was further confirmed by immunohistochemical staining.Results: Significant induction of chondrogenic differentiation in the miR-140-5p-hUC-MSCs (140-MSCs), while its proliferation was not influenced. Interestingly, intra-articular injection of 140-MSCs significantly enhanced articular cartilage self-repairing in comparison to normal hUC-MSCs. Moreover, we noticed that intra-articular injection of high 140-MSCs numbers reinforces cells assembling on the impaired cartilage surface and subsequently differentiated into chondrocytes.Conclusions: In conclusion, these results indicate therapeutic superiority of hUC-MSCs overexpressing miR-140-5p to treat OA using intra-articular injection. [ABSTRACT FROM AUTHOR]

Tendinopathy, which is characterized by the ectopic ossification of tendon, is a common disease occurring in certain population, such as athletes that suffer from repetitive tendon strains. However, the molecular mechanism underlying the pathogenesis of tendinopathy caused by the overuse of tendon is still lacking. Here, we found that the mechanosensitive miRNA, miR-337-3p, had lower expression under uniaxial cyclical mechanical loading in tendon-derived stem cells (TDSCs) and negatively controlled chondro-osteogenic differentiation of TDSCs. Importantly, downregulation of miR-337-3p expression was also observed in both rat and human calcified tendons, and overexpressing miR-337-3p in patellar tendons of rat tendinopathy model displayed a robust therapeutic efficiency. Mechanistically, we found that the proinflammatory cytokine interleukin-1 β was the upstream factor of miR-337-3p that bridges the mechanical loading with its downregulation. Furthermore, the target genes of miR-337-3p, NADPH oxidase 4, and insulin receptor substrate 1, activated chondro-osteogenic differentiation of TDSCs through JNK and ERK signaling, respectively. Thus, these findings not only provide novel insight into the molecular mechanisms underlying ectopic ossification in tendinopathy but also highlight the significance of miR-337-3p as a putative therapeutic target for clinic treatment of tendinopathy. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a highly prevalent and debilitating joint disorder characterized by the degeneration of articular cartilage. However, no effective medical therapy has been found yet for such condition. In this study, we directly confirmed the existence of articular cartilage stem cells (ACSCs) in vivo and in situ for the first time both in normal and OA articular cartilage, and explored their chondrogenesis in Interleukin-1β (IL-1β) induced inflammation environment and disclose whether the inhibition of NF-κB signaling can induce ACSCs activation thus improve the progression of experimental OA. We found an interesting phenomenon that ACSCs were activated and exhibited a transient proliferative response in early OA as an initial attempt for self-repair. During the in vitro mechanism study, we discovered IL-1β can efficiently activate the NF-κB pathway and potently impair the responsiveness of ACSCs, whereas the NF-κB pathway inhibitor rescued the ACSCs chondrogenesis. The final in vivo experiments further confirmed ACSCs' activation were maintained by NF-κB pathway inhibitor, which induced cartilage regeneration, and protected articular cartilage from injury in an OA animal model. Our results provided in vivo evidence of the presence of ACSCs, and disclosed their action in the early OA stage and gradual quiet as OA process, presented a potential mechanism for both cartilage intrinsic repair and its final degradation, and demonstrated the feasibility of inducing endogenous adult tissue-specific mesenchymal stem cells for articular cartilage repair and OA therapy. S tem C ells 2015;33:3125-3137 [ABSTRACT FROM AUTHOR]

Severe or prolonged inflammatory response caused by infection or biomaterials leads to delayed healing or bone repair failure. This study investigated the important roles of the proinflammatory cytokines of the interleukin-12 (IL-12) family, namely, IL-12 and IL-23, in the inflammation-mediated inhibition of bone formation in vivo. IL-12p40 -/- mice lacking IL-12 and IL-23 exhibited enhanced bone formation. IL-12 and IL-23 indirectly inhibited bone marrow mesenchymal stem cell (BMMSC) differentiation by stimulating CD4 + T cells to increase interferon γ (IFN-γ) and IL-17 levels. Mechanistically, IL-17 synergistically enhanced IFN-γ-induced BMMSC apoptosis. Moreover, INF-γ and IL-17 exerted proapoptotic effects by upregulating the expression levels of Fas and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), as well as by activating the caspase cascade in BMMSCs. IL-12p40 depletion in mice could promote ectopic bone formation. Thus, IL-12p40 is an attractive therapeutic target to overcome the inflammation-mediated inhibition of bone formation in vivo.