A new version of the Peng–Robinson equation of state (PR EOS) is developed through the use of Wertheim's thermodynamic perturbation theory of associating fluids and statistical associating fluid ...theory (SAFT). The new equation is characterized by two temperature-independent parameters, namely, association strength and association volume, which account for the association interactions between associating molecules. In this work, we employed the equation to model aspirin and naproxen solubility enhancement obtained in the ternary supercritical CO
2/alcohol systems, where the original PR EOS has resulted in large and negative binary interaction parameters between the polar solute and polar cosolvent. Calculated results show that the Peng–Robinson EOS plus association model gives better performance to correlate these ternary solubility data over the ranges of temperature, pressure and cosolvent concentration investigated than its conventional form that uses temperature-dependent parameters.
With advances in biomedical methods, tissue-engineered materials have developed rapidly as an alternative to nerve autografts for the repair of peripheral nerve injuries. However, the materials ...selected for use in the repair of peripheral nerve injuries, in particular multiple injuries and largegap defects, must be chosen carefully. Various methods and materials for protecting the healthy tissue and repairing peripheral nerve injuries have been described, and each method or material has advantages and disadvantages. Recently, a large amount of research has been focused on tissue-engineered materials for the repair of peripheral nerve injuries. Using the keywords ＂peripheral nerve injury＂, ＂autotransplant＂, ＂nerve graft＂, and ＂biomaterial＂, we retrieved publications using tissue-engineered materials for the repair of peripheral nerve injuries appearing in the Web of Science from 2010 to 2014. The country with the most total publications was the USA. The institutions that were the most productive in this field include Hannover Medical School （Germany）, Washington University （USA）, and Nantong University （China）. The total number of publications using tissue-engineered materials for the repair of peripheral nerve injuries grad- ually increased over time, as did the number of Chinese publications, suggesting that China has made many scientific contributions to this field of research.
Cerebral ischemia remains the most frequent cause of death and quality-of-life impairments due to neurological deficits, and accounts for the majority of total healthcare costs. However, treatments ...for cerebral ischemia are limited. Over the last decade, bone marrow stromal cell （BMSC） therapy has emerged as a particularly appealing option, as it is possible to help patients even when initiated days or even weeks after the ischemic insult. BMSCs are a class of multipotent, self-renewing cells that give rise to differentiated progeny when implanted into appropriate tissues. Therapeutic effects of BMSC treatment for ischemic stroke, including sensory and motor recovery, have been reported in pre-clinical studies and clinical trials. In this article, we review the recent progress in BMSC-based therapy for ischemic stroke, focusing on the route of delivery and pre-processing of BMSCs. Selecting an optimal delivery route is of particular importance. The ideal approach, as well as the least risky, for translational applications still requires further identification. Appropriate pre- processing of BMSCs or combination therapy has the benefit of achieving the maximum possible restoration. Further pre-clinical studies are required to determine the time-window for transplantation and the appropriate dosage of cells.
Network polymers in a rubber or a gel often contain non-uniform chain lengths. By means of dynamic Monte Carlo simulations of polymer mixtures with various compositions of two chain lengths, we ...investigated how the factor of polydispersity influences their strain-induced crystal nucleation. Under a high temperature and a high strain rate, the stretching of both polymers revealed that crystal nucleation is mainly accelerated by the presence of short-chain polymers; nevertheless, both polymers join together in the nucleation process. Further analysis proved that crystal nucleation is initiated from those highly stretched short segments, which are rich on the short-chain polymers.
Direct transformation of ethanol to ethyl acetate was investigated on a series of Cu（ZrO2）/SiO2 catalysts. Inductively coupled plasma（ICP）, surface area analysis, X-ray diffraction（XRD）, ...H2-temperature programmed reduc- tion（H2-TPR）, X-ray photoelectron spectroscopy（XPS）, NH3-temperature programmed desorption（NH3-TPD） and Fourier transform-infrared spectroscopy（FTIR） techniques were used to characterize the catalysts. The results reveal that ZrO2 can improve the dispersion of copper species and increase the acidity of the Cu（ZrO2）/SiO2 catalysts. The Cu0 is responsible for ethanol dehydrogenation to acetaldehyde, and both the Lewis acid and Bronsted acid sites were in favor of the selectivity to ethyl acetate. The synergistic effect of Cu0 and an appropriate amount of acidic sites played an important role in the production of ethyl acetate.
Sorafenib is the first-line medication for advanced hepatocellular carcinoma (HCC), but it can only extend limited survival. It is imperative to find a combination strategy to increase sorafenib ...efficacy. Artesunate is such a preferred candidate, because artesunate is clinically well-tolerated and more importantly both drugs can induce ferroptosis through different mechanisms. In this study we investigated the combined effect of sorafenib and artesunate in inducing ferroptosis of HCC and elucidated the involved molecular mechanisms. We showed that artesunate greatly enhanced the anticancer effects of low dose of sorafenib against Huh7, SNU-449, and SNU-182 HCC cell lines in vitro and against Huh7 cell xenograft model in Balb/c nude mice. The combination index method confirmed that the combined effect of sorafenib and artesunate was synergistic. Compared with the treatment with artesunate or sorafenib alone, combined treatment induced significantly exacerbated lipid peroxidation and ferroptosis, which was blocked by N-acetyl cysteine and ferroptosis inhibitors liproxstatin-1 and deferoxamine mesylate, but not by inhibitors of other types of cell death (z-VAD, necrostatin-1 and belnacasan). In Huh7 cells, we demonstrated that the combined treatment induced oxidative stress and lysosome-mediated ferritinophagy, two essential aspects of ferroptosis. Sorafenib at low dose mainly caused oxidative stress through mitochondrial impairments and SLC7A11-invovled glutathione depletion. Artesunate-induced lysosome activation synergized with sorafenib-mediated pro-oxidative effects by promoting sequential reactions including lysosomal cathepsin B/L activation, ferritin degradation, lipid peroxidation, and consequent ferroptosis. Taken together, artesunate could be repurposed to sensitize sorafenib in HCC treatment. The combined treatment can be easily translated into clinical applications.
Metal–organic frameworks (MOFs), a new class of porous crystalline materials, have attracted great interest as a promising candidate for sustainable energy and environmental remediation. In this ...study, ZIF-8, a versatile MOF based on imidazolate ligands, was selected as a photocatalyst to decompose methylene blue (MB) under UV light irradiation. The influence factors, kinetics, and mechanism of photocatalytic MB degradation and stability of ZIF-8, were also studied. The results revealed that the ZIF-8 photocatalyst exhibited efficiently photocatalytic activity for MB degradation under UV irradiation, which was confirmed through the detection of hydroxyl radicals (˙OH) by a fluorescence method. The MB degradation over the ZIF-8 photocatalyst followed a pseudo-first-order kinetics model. ZIF-8 worked effectively over a wide pH range from 4.0 to 12.0, and showed both high adsorption capacity and degradation efficiency for MB in a strong alkaline environment. The enhanced efficiency in a strong alkaline environment resulted from the higher charged ZIF-8 (pH > pH pzc ) and the elevated yield of ˙OH facilitated by increased OH − concentration. The possible pathway of photocatalytic degradation of MB in ZIF-8 was proposed. The results indicated that ZIF-8 can be used as a highly efficient photocatalyst to decompose organic pollutants.
Disrupted Wnt signaling in osteoblastic-lineage cells leads to bone formation defect in osteoporosis. However, the factors repressing Wnt signaling are unclear. In our study, we found that Wnt ...signaling was suppressed persistently in bone marrow-derived mesenchymal stem cells (BMSCs) during osteoporosis. Accordingly, histone acetylation levels on Wnt genes (Wnt1, Wnt6, Wnt10a, and Wnt10b) were declined in BMSCs from OVX mice. By screening the family of histone acetyltransferase, we identified that GCN5 expression increased during osteogenic differentiation of BMSCs, whereas decreased after osteoporosis. Further analysis revealed that GCN5 promoted osteogenic differentiation of BMSCs by increasing acetylation on histone 3 lysine 9 loci on the promoters of Wnt genes. Reduced GCN5 expression suppressed Wnt signaling, resulting in osteogenic defect of BMSCs from OVX mice. Moreover, restoring GCN5 levels recovered BMSC osteogenic differentiation, and attenuated bone loss in OVX mice. Taken together, our study demonstrated that disrupted histone acetylation modification in BMSCs lead to bone formation defect during osteoporosis. The findings also introduced a novel therapeutic target for osteoporosis.
By computer research, the literature of clinical and experimental studies on moxibustion therapy for chronic gastritis in the recent fifteen years was collected, sorted and analyzed, in order to ...understand the general situation about the clinical and experimental studies on moxibustion therapy for chronic gastritis, summarize the regularity of moxibustion therapy for chronic gastritis, so as to guide the treatment of chronic gastritis.
ABSTRACT
Angiogenesis is disrupted in age‐related and postmenopausal osteoporosis. However, the mechanisms of the disorder remain elusive. We confirmed in this study that, in accordance with the ...decrease of H‐type vessels, the proangiogenic potential of bone marrow‐derived mesenchymal stem cells (BMSCs) declined during osteoporosis. Screening of the histone acetyltransferase family revealed that GCN5 decreased in BMSCs derived from osteoporotic femur. Further analysis identified that GCN5 plays important roles in regulating the proangiogenic potential of BMSCs. GCN5 promoted BMSC‐mediated angiogenesis by enhancing H3K9ac levels on the promoter of Vegf. The decrease of GCN5 in osteoporotic BMSCs led to the decline of proangiogenic capacity. Accordingly, overexpression of GCN5 enhanced the proangiogenic potency of osteoporotic BMSCs. Furthermore, recovering GCN5 expression in vivo by lentiviral expression vector significantly attenuated the loss of angiogenesis in ovariectomized mouse femurs. Our study results revealed an epigenetic mechanism controlling BMSC‐mediated angiogenesis and provided a novel therapeutic target for osteoporosis treatment.—Jing, H., Liao, L., Su, X., Shuai, Y. Zhang, X., Deng, Z., Jin, Y. Declining histone acetyltransferase GCN5 represses BMSC‐mediated angiogenesis during osteoporosis. FASEB J. 31, 4422–4433 (2017). www.fasebj.org
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