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Abstract Background Cells and tissues, such as macrophages, express inducible nitric oxide synthase (INOS) after stimulation by certain factors. INOS helps mediate the macrophage inflammatory reaction, but few studies have explored how INOS affects macrophage function in nonalcoholic fatty liver disease (NAFLD). Objective This study investigated the role of INOS‐mediated macrophage activity in NAFLD. Methods A high‐fat diet was used to establish an NAFLD mouse model. After 12 weeks, blood was collected for immune cell and lipid analyses, and liver tissues were collected for pathological analyses with hematoxylin and eosin and Oil Red O staining. Peritoneal macrophages were extracted in situ, cultured in Dulbecco's modified Eagle's medium, and stimulated with palmitic acid to mimic in vivo conditions for further assays. Real‐time polymerase chain reaction, western blot analysis, and immunofluorescence were used to verify the expression of target genes or proteins. Results In the NAFLD model, INOS expression in macrophages increased, and INOS knockdown significantly decreased the number of macrophages. Pathological examinations confirmed that INOS knockdown slowed NAFLD progression and macrophage infiltration during inflammation. INOS knockdown also enhanced phagocytosis and lipid transport by macrophages, and increased the expression of autophagy‐related molecules in macrophages, which improved the autophagy level, promoted apoptotic cell degradation, and maintained intracellular environment homeostasis. Conclusions These results indicate a correlation between INOS expression and macrophage function in NAFLD.

In this study, a novel family of single-phase, bridgeless, three-level power factor correction (PFC) topologies was proposed based on the embedded construction scheme. These technologies combined bridgeless PFC circuits and multilevel technology. These topologies are highly suitable for applications with high efficiency and high power density requirements. This family has six topologies. The derivation, operating principle, mathematical model, and circuit performance of the proposed topologies were analyzed. Furthermore, for this family of topologies, a four-carrier phase disposition pulse width modulation (FCPD-PWM) method and a system design method were proposed. Finally, an experimental prototype with an output power of 1 kW was designed. The circuit can work in the PFC mode under the rated working conditions and reflects the characteristics of three levels. The circuit can respond quickly and work normally under a variety of complex working conditions and can work in a diode rectification mode when the driving voltage signal is lost. The experimental results demonstrated the feasibility of the topology derived from the proposed embedded construction scheme and the effectiveness of the FCPD-PWM method for driving the proposed three-level conversion circuit.

Abstract Background Osteoporosis is a common metabolic skeletal disease and usually lacks obvious symptoms. Many individuals are not diagnosed until osteoporotic fractures occur. Bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) is the gold standard for osteoporosis detection. However, only a limited percentage of people with osteoporosis risks undergo the DXA test. As a result, it is vital to develop methods to identify individuals at-risk based on methods other than DXA. Results We proposed a hierarchical model with three layers to detect osteoporosis using clinical data (including demographic characteristics and routine laboratory tests data) and CT images covering lumbar vertebral bodies rather than DXA data via machine learning. 2210 individuals over age 40 were collected retrospectively, among which 246 individuals’ clinical data and CT images are both available. Irrelevant and redundant features were removed via statistical analysis. Consequently, 28 features, including 16 clinical data and 12 texture features demonstrated statistically significant differences (p

The complexation-excessive impregnation modification method, which was original in this study, and the ion-exchange method and the in situ modification method were used to synthesize Ni-modified SAPO-11 molecular sieves. With the Ni-modified SAPO-11 samples as support, the corresponding NiWS-supported catalysts for the hydroisomerization of n-hexadecane were prepared. The effects of Ni-modification on SAPO-11 characteristics and the active phase were studied. The structure, morphology, and acidity of SAPO-11, as well as the interaction between active metals and support, the morphology, dispersibility, and stacking number of the active phase, were all changed by Ni-modification methods. The complexation-excessive impregnation modification method deleted a portion of Al from SAPO-11 molecular sieves while simultaneously integrating Ni into the skeletal structure of the surface layer of SAPO-11 molecular sieves, considerably enhancing the acidity of SAPO-11 molecular sieves. Furthermore, during dealumination, ethylenediaminetetraacetic acid generated more mesoporous structures and increased the mesoporous volume of SAPO-11 molecular sieves. Because the complexation-excessive impregnation modification method increased the amount of Ni in the surface framework of the SAPO-11 molecular sieve, it has weakened the interaction between the active phase and the support, improved the properties of the active phase, and greatly improved the hydroisomerization performance of NiW/NiSAPO-11. The yield of i-hexadecane of NiW/NiSAPO-11 increased by 39.3% when compared to NiW/NiSAPO-11. It presented a realistic approach for increasing the acidity of SAPO-11, reducing the interaction between active metals and support, and improving the active phase stacking problem.

Numerous clinical studies investigated how low expression of CD9 predicts poor prognosis of solid tumor. However, the results were inconclusive. This present meta-analysis was therefore performed to determine the prognostic value of CD9 expression in solid tumors. In this meta-analysis, 25 studies involving 5,555 participants were included; the result showed strong significant associations between declined expression of CD9 and all endpoints: overall survival (OS) (hazard ratio (HR) = 1.88, 95% CI = 1.45–2.43, p < 0.000) and time to progression (TTP) (HR = 2.0, 95% CI = 1.38–2.88, p < 0.000). The subgroup analysis was also performed, which revealed that the associations between CD9 downregulated expression related to poor OS in lung cancer and head and neck cancer. Also, low expression of CD9 was significantly connected with poor TTP in patients with head and neck cancer. The adverse prognostic impact of decreased expression of CD9 was observed in patients of different ethnicities. In conclusion, these results showed that declined expression of CD9 was associated with poor survival in human solid tumors. CD9 may be a valuable prognostic predictive biomarker and a potential therapeutic target in human solid tumors.

SAPO-11 molecular sieves were modified with different Ni contents by the in situ modification method. The Ni-modified SAPO-11 molecular sieves were used as the supports to prepare the corresponding NiW-supported catalysts for the hydroisomerization of n-hexadecane. The Ni-modified SAPO-11 and the corresponding NiW-supported catalysts were characterized by X-ray diffraction, scanning electron microscopy, N2 adsorption–desorption, NH3-temperature-programmed desorption, pyridine adsorbed infrared, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The results showed that Ni in situ modification preserved the crystal structure of SAPO-11; increased the BET specific surface area, mesopore volume, and medium and strong Brønsted acid amount of SAPO-11; and increased the stacking number of the active phase of the catalysts. 3Ni-SAPO-11 possessed the largest BET specific surface area, mesopore volume, and medium and strong Brønsted acid amount. NiW/3Ni-SAPO-11 possessed the highest dispersion of the active phase and the highest sulfidation degree of the active metals. The results of the hydroisomerization of n-hexadecane showed that Ni in situ modification improved the catalytic activity and selectivity of the catalysts for the hydroisomerization of n-hexadecane to varying degrees. Especially, NiW/3Ni-SAPO-11 had the highest catalytic activity and isomer selectivity, and the maximum yield of isomeric hexadecane could reach 71.18%.

Escin, a natural triterpene saponin mixture obtained from the horse chestnut tree (Aesculus hippocastanum), has been used for the treatment of chronic venous insufficiency (CVI), hemorrhoids, and edema. However, it is unclear how escin protects against endothelial barrier dysfunction induced by pro‐inflammatory high mobility group protein 1 (HMGB1). Here, we report that escin can suppress (a) HMGB1‐induced overexpression of the aquaporin‐1 (AQP1) water channel in endothelial cells and (b) HMGB1‐induced increases in endothelial cell permeability. This is the first report that escin inhibits AQP1 and alleviates barrier dysfunction in HMGB1‐induced inflammatory response.

Progranulin is closely related to neuronal survival in a neuroinflammatory mouse model and attenuates inflammatory reactions. Atsttrin is an engineered protein composed of three progranulin fragments and has been shown to have an effect similar to that of progranulin. Atsttrin has anti-inflammatory actions in multiple arthritis mouse models, and it protects against further arthritis development. However, whether Atsttrin has a role in neuroinflammation remains to be elucidated. In this study, we produced a neuroinflammatory mouse model by intracerebroventricular injection of 1 μL lipopolysaccharide (10 μg/μL). Atsttrin (2.5 mg/kg) was administered via intraperitoneal injection every 3 days over a period of 7 days before intracerebroventricular injection of 1 μL lipopolysaccharide (10 μg/μL). In addition, astrocyte cultures were treated with 0, 100 or 300 ng/mL lipopolysaccharide, with 200 ng/mL Atsttrin simultaneously. Immunohistochemistry, enzyme-linked immunosorbent assay and real-time reverse transcription-polymerase chain reaction were performed to examine the protein and mRNA levels of inflammatory mediators and to assess activation of the nuclear factor kappa B signaling pathway. Progranulin expression in the brain of wild-type mice and in astrocyte cultures was increased after lipopolysaccharide administration. The protein and mRNA expression levels of tumor necrosis factor-α, interleukin-1β and inducible nitric oxide synthase were increased in the brain of progranulin knockout mice after lipopolysaccharide administration. Atsttrin treatment reduced the lipopolysaccharide-induced increase in the protein and mRNA levels of tumor necrosis factor-α, interleukin-1β, matrix metalloproteinase-3 and inducible nitric oxide synthase in the brain of progranulin knockout mice. Atsttrin also reduced the expression of cyclooxygenase-2, inducible nitric oxide synthase and matrix metalloproteinase 3 mRNA in lipopolysaccharide-treated astrocytes in vitro, and decreased the concentration of tumor necrosis factor a and interleukin-1β in the supernatant. Furthermore, Atsttrin significantly reduced the levels of phospho-nuclear factor kappa B inhibitor a in the brain of lipopolysaccharide-treated progranulin knockout mice and astrocytes, and it decreased the expression of nuclear factor kappa B2 in astrocytes. Collectively, our findings show that the anti-neuroinflammatory effect of Atsttrin involves inhibiton of the nuclear factor kappa B signaling pathway, and they suggest that Atsttrin may have clinical potential in neuroinflammatory therapy. The study was approved by the Animal Ethics Committee of Qilu Hospital of Shandong University, China (approval No. KYLL-2015(KS)-088) on February 10, 2015.

Background Osteosarcoma (OS) is the most common malignant primary bone tumor occurring in children and young adults, which occupies the second important cause of tumor-associated deaths among children and young adults. Recent studies have demonstrated that many microRNAs (miRNAs) have abnormal expression in OS, and can function as prognostic factors of OS patients. However, no previous studies have comprehensively analyzed the relationship between multiple miRNAs and prognosis of OS patients. Methods A total of 63 OS patients were retrospectively enrolled. The clinical characteristics were collected, and the expression levels of miRNA-21, miRNA-30c, miRNA-34a, miRNA-101, miRNA-133a, miRNA-214, miRNA-218, miRNA-433 and miRNA-539 in tumor tissues were measured through quantitative real-time polymerasechain reaction. Kaplan–Meier analysis was used to perform univariate survival analysis, and Cox regression model was used to perform multivariate survival analysis which included the variables with P < 0.1 in univariate survival analysis. Results The cumulative survival for 1, 2 and 5 years was 90.48%, 68.25% and 38.10%, respectively, and mean survival time was (45.39 ± 3.60) months (95% CI [38.34–52.45]). Kaplan–Meier analysis demonstrated that TNM stage, metastasis or recurrence, miRNA-21, miRNA-214, miRNA-34a, miRNA-133a and miRNA-539 were correlated with cum survival, but gender, age, tumor diameter, differentiation, miRNA-30c, miRNA-433, miRNA-101 and miRNA-218 were not. Multivariate survival analysis demonstrated that miRNA-21 (hazard ratio (HR): 3.457, 95% CI [2.165–11.518]), miRNA (HR: 3.138, 95% CI [2.014–10.259]), miRNA-34a (HR: 0.452, 95% CI [0.202–0.915]), miRNA-133a (HR: 0.307, 95% CI [0.113–0.874]) and miRNA-539 (HR: 0.358, 95% CI [0.155–0.896]) were independent prognostic markers of OS patients after adjusting for TNM stage (HR: 2.893, 95% CI [1.496–8.125]), metastasis or recurrence (HR: 3.628, 95% CI [2.217–12.316]) and miRNA-30c (HR: 0.689, 95% CI [0.445–1.828]). Conclusions High expression of miRNA-21 and miRNA-214 and low expression of miRNA-34a, miRNA-133a and miRNA-539 were associated with poor prognosis of OS patients after adjusting for TNM stage, metastasis or recurrence and miRNA-30c.

Selective catalytic reduction of NOx with NH3 (NH3-SCR) has been widely investigated to reduce NOx emissions from combustion processes, which cause environmental challenges. However, most of the current work on NOx reduction has focused on using feed gas without CO2 or containing small amounts of CO2. In the future, oxy-fuel combustion will play an important role for power generation, and this process generates high concentrations of CO2 in flue gas. Therefore, studies on the SCR process under concentrated CO2 atmosphere conditions are important for future SCR deployment in oxy-fuel combustion processes. In this work, Mn- and Ce-based catalysts using activated carbon as support were used to investigate the effect of CO2 on NO conversion. A N2 atmosphere was used for comparison. Different process conditions such as temperature, SO2 concentration, H2O content in the feed gas and space velocity were studied. Under Mn-Ce/AC conditions, the results suggested that Mn metal could reduce the inhibition effect of CO2 on the NO conversion, while Ce metal increased the inhibition effect of CO2. High space velocity also resulted in a reduction of CO2 inhibition on the NO conversion, although the overall performance of SCR was greatly reduced at high space velocity. Future investigations to design novel Mn-based catalysts are suggested to enhance the SCR performance under concentrated CO2 atmosphere conditions.

Photo-chemical smog and acid rain formed from many pollutants including NOx are serious problems that have attracted much attention due to their negative influences on the atmosphere, plants, animals and even building materials. Effective measures of controlling NOx emissions are necessary. In this study, a computational fluid dynamics (CFD) software, Ansys Fluent 14.5, has been applied to research the processes of South American coal (SAm) reburning and cornstalk reburning. The influences of reburn zone excess air coefficient, reburning fuel fraction (Rff) and the secondary air temperature on the furnace combustion and NOx reduction have been determined. Results show that, in the simulated data range, the lower reburn zone excess air coefficient, the greater the rate of denitration for both SAm reburning and cornstalk reburning. The highest rates of denitration for SAm reburning and cornstalk reburning were 56.15% and 66.89%, respectively, in comparison to the conventional combustion. The denitration rate increases with the increase of reburning fuel fraction. However, when the reburning fuel fraction increases beyond a certain level, fuels within the furnace will undergo incomplete combustion. Under the premise of the fuel burnout, a relatively good case occurs at the reburning fuel fraction of 20% for the two kinds of reburning, and the NOx removal rate is 60.57% for cornstalk reburning, which is 7.61% higher than that of the SAm reburning. Temperature also has certain influences on the denitration effect and it shows that, in the lower temperature range, the higher the temperature of the secondary air, the higher the denitration rate. However, as temperature reaches a certain value, the denitration effect is no longer enhanced but reduced. For the two kinds of reburning, the case with the secondary air at 500 K is a relatively good one, and the NOx removal rate reaches 66.36% for cornstalk reburning, while it is 55% for SAm reburning. Overall, cornstalk reburning provides a higher NOx reduction rate in comparison to SAm reburning.

SpyTag can spontaneously form a covalent isopeptide bond with its protein partner SpyCatcher. Firefly luciferase from Photinus pyralis was cyclized in vivo by fusing SpyCatcher at the N terminus and SpyTag at the C terminus. Circular LUC was more thermostable and alkali-tolerant than the wild type, without compromising the specific activity. Structural analysis indicated that the cyclized LUC increased the thermodynamic stability of the structure and remained more properly folded at high temperatures when compared with the wild type. We also prepared an N-terminally and C-terminally shortened form of the SpyCatcher protein and cyclization using this truncated form led to even more thermostability than the original form. Our findings suggest that cyclization with SpyTag and SpyCatcher is a promising and effective strategy to enhance thermostability of enzymes.

Cancer stem cell (CSC) theory has been proposed and verified in many cancers. The existence of osteosarcoma CSCs has been confirmed for many years and multiple surface markers have been employed to identify them. In this study, we identified CD271(+) subpopulation of osteosarcoma displaying stem-like properties. CD271, known as the neural crest nerve growth factor receptor, is the marker of bone marrow mesenchymal stem cells (MSCs) and human melanoma-initiating cells. We discovered that CD271 was expressed differentially in diverse types of human osteosarcoma and stabilized cell lines. CD271(+) osteosarcoma cells displayed most of the properties of CSC, such as self-renewal, differentiation, drug resistance and tumorigenicity in vivo. Nanog, Oct3/4, STAT3, DNA-PKcs, Bcl-2 and ABCG2 were more expressed in CD271(+) cells compared with CD271- cells. Our study supported the osteosarcoma CSC hypothesis and, to a certain extent, revealed one of the possible mechanisms involved in maintaining CSCs properties.