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Titanium (Ti) based spinal fusion cages are frequently used in the clinics for the treatment of spinal degeneration and related diseases, however, their further clinical application is generally harassed by several drawbacks such as stress shielding, non-biodegradability and additional bone grafting procedure. Our earlier work has demonstrated the efficacy of a biodegradable macro-porous polycaprolactone-tricalcium phosphate (PCL-TCP) composite scaffold in promoting bony tissue ingrowth as well as its ability to sustain mechanical loads upon implantation into an orthotopic defect site. In this study, we investigated the use of PCL-TCP scaffold as an autograft-free spinal fusion cage in a preclinical sheep model over 12 months, and compared the fusion efficacy against Ti cages incorporated with autografts. Results showed that despite PCL-TCP scaffold as an autograft-free cage attaining a slower fusion rate at early stage (6 month), it achieved similar degree of spinal fusion efficacy as Ti cages aided with autograft at 12 month post-operation as evidenced by the radiographic and histological evaluation. PCL-TCP cages alone demonstrated better bone ingrowth with 2.6 fold higher bone/interspace ratio (B/I) and more homogeneous bone tissue distribution compared with that of the Ti cages (88.10 ± 3.63% vs. 33.74 ± 2.78%, p < 0.05) as seen from the histological and micro-CT analysis. Moreover, besides the bone tissue ingrowth, a quantitative approach was illustrated to accurately evaluate the osteointegration of fusion cage with surrounding bone tissue, and showed a 1.36 fold higher degree of osteointegration occurred in PCL-TCP cage group than Ti cage group (CS/PC: 79.31 ± 3.15% vs 58.44 ± 2.43%, p < 0.05). Furthermore, biomechanical analysis showed comparable mechanical strength of fused segments in both groups in terms of the range of motion and stiffness at 12 month (p > 0.05). The degradation profile of the PCL-TCP cages was noted to increase in tandem with new bone ingrowth into the pores, while maintaining good structural integrity necessary for supporting the spinal interbody segments. Therefore, with the better osteointegration, more bone tissue ingrowth as well as its favorable biodegradable and radiolucent properties, PCL-TCP cage has been demonstrated to be a promising candidate as an autograft-free fusion cage for clinical application. [ABSTRACT FROM AUTHOR]

Abstract: Eleven compounds were isolated from potato peels and identified. Their structures were determined by interpretation of UV, MS, 1D, and 2D NMR spectral data and by comparison with reported data. The main components of the potato peels were found to be chlorogenic acid and other phenolic compounds, accompanied by 2 glycoalkaloids, 3 low-molecular-weight amide compounds, and 2 unsaturated fatty acids, including an omega-3 fatty acid. The potato peels showed more potent radical scavenging activity than the flesh. The quantification of the 11 components indicated that the potato peels contained a higher amount of phenolic compounds than the flesh. These results suggest that peel waste from the industry of potato chips and fries may be a source of useful compounds for human health. [Copyright &y& Elsevier]

Dendrobium officinale is an important traditional Chinese medicinal herb, and the stem tissue is the main medicinal that is harvested from D. officinale. Recently, the first viroid was identified from D. officinale in China, and it has been named Dendrobium viroid (DVd). Whether DVd interferes with metabolic pathways in dendrobium plants and affects the medicinal value of the host is unknown. In this study, metabolomics data from stem tissues supported by transcriptome studies were used to investigate how metabolism modulate of D. officinale is altered by DVd infection. Our results show that metabolism of D. officinale is reprogrammed in many ways during DVd infection, and this is reflected by significant changes in the levels of flavonoids, alkaloids, and phenolic acids. Furthermore, we found that DVd infection significantly decreased the accumulation of flavonoids and alkaloid metabolites in infected stems, and the decreases in these metabolites appears to affect the medicinal components of the infected plants, weakening the host antiviral immune response as well. Conversely, phenolic acids occupy a larger proportion of the up-regulated metabolites from DVd infection in comparison with the mock-inoculated control, and the increase in the total phenolic acids may reflect the activation of the pathogen defense response in D. officinale. Taken together, our results provide an interesting overview and give a better understanding of the relationship between metabolism and DVd infection in the orchid D. officinale. [ABSTRACT FROM AUTHOR]

A series of mesoporous SiO2&z.sbnd;ZrO2 aerogels with various zirconia content (10–90 wt%) were prepared by the sol–gel method followed by supercritical drying. The characterization of aerogels is performed by XRD, FT-IR, 29Si liquid-state NMR, and BET-N2 adsorption. The results showed that (i) the aerogels have type VI (BDDT) profile which is the typical of mesopores in the interval between 2 nm; (ii) the specific surface areas varied from 340 to 730 m2/g with (SBET)MAX=735.5 m2/g for the aerogel with 10 wt% zirconia and the surface areas decreased with the increase of zirconia; (iii) all the aerogels with different zirconia content remained amorphous or poorly crystallized after calcination in air at 500 °C; (iv) a large number of Si&z.sbnd;O&z.sbnd;Zr bands existed in the aerogels indicating a homogeneous distribution of the components on the atomic scale. In addition, using inorganic salt as zirconium source instead of the expensive and toxic zirconium alkoxide is very economic. [Copyright &y& Elsevier]

The construction and operation of large-scale reservoirs changes the flow regimes downstream, and thus has negative impact on the aquatic organisms. As an important indicator species, fish is sensitive to flow regimes, which provide stimulus for physiological activity, such as spawning and immigration. On the other hand, the grid-connected large-scale hydropower stations often carry out multiple functions, such as power generation, peak shaving, flood control, and navigation, involving multiple subjects including power plant, power grid, etc. In this study, a multi-objective optimization model is proposed considering the power generation requirement of the power plant, the firm power requirement of the power grid, and the ecological requirement of the fish spawning downstream, simultaneously. The flow regimes is firstly identified and characterized, and the reservoir discharge similar to the natural status is preferred. The proposed model is solved by Non-dominated Sorting Genetic Algorithm II (NSGA-II), and applied to a large-scale reservoir in planning on the upper reaches of the Yellow River in China, where the spawning ground of the plateau cold water fishes will be influenced. The results indicate that the proposed methodology can achieve some balance among different objectives from different subjects, and can be generalized to other large-scale reservoirs that has great impact on the flow regimes downstream. • Considering fish spawning requirement in seasonal hydropower scheduling problem based on characteristics of flow regimes. • Multi-objective optimization maximizing firm power, power generation, and ecological requirement simultaneously. • The proposed method was applied to a real-world reservoir being built. [ABSTRACT FROM AUTHOR]

: Alzheimer's disease (AD) is closely related to abnormal glucose metabolism in the central nervous system. Progesterone has been shown to have obvious neuroprotective effects in the pathogenesis of AD, but the specific mechanism has not been fully elucidated. Therefore, the purpose of this study was to investigate the effect of progesterone on the glucose metabolism of neurons in amyloid precursor protein (APP)/presenilin 1 (PS1) mice and Aβ-induced AD cell model. :APP/PS1 mice were treated with 40 mg/kg progesterone for 40 days and primary cultured cortical neurons were treated with 1 μM progesterone for 48 h.Then behavior tests,2-NBDG glucose uptake tests and the protein levels of glucose transporter 3 (GLUT3), GLUT4, cAMP-response element binding protein (CREB) and proliferator-activated receptor γ (PPARγ) were examined. :Progesterone increased the expression levels of GLUT3 and GLUT4 in the cortex of APP/PS1 mice, accompanied by an improvement in learning and memory. Progesterone increased the levels of CREB and PPARγ in the cerebral cortex of APP/PS1 mice. In vitro, progesterone increased glucose uptake in primary cultured cortical neurons, this effect was blocked by the progesterone receptor membrane component 1 (PGRMC1)-specific blocker AG205 but not by the progesterone receptor (PR)-specific blocker RU486. Meanwhile, progesterone increased the expression of GLUT3, GLUT4, CREB and PPARγ, and AG205 blocked this effect. These results confirm that progesterone significantly improves the glucose metabolism of neurons.One of the mechanisms of this effect is that progesterone upregulates protein expression of GLUT3 and GLUT4 through pathways PGRMC1/CREB/GLUT3 and PGRMC1/PPARγ/GLUT4. [ABSTRACT FROM AUTHOR]

In this study, the enzyme-assisted extraction of polysaccharides from Lentinus edodes (LEPs) was optimized by response surface methodology, and a preliminary characterization of the extracted LEPs and their anti-proliferative activities were investigated. An orthogonal assay was constructed to determine the optimal amounts of cellulase, papain and pectinase, which were 15, 20 and 15 g/kg, respectively. Then effects of extraction conditions were evaluated and optimized using a Box-Behnken design. The results showed that the highest polysaccharides yield of 15.65% was achieved with an extraction temperature of 54 °C, pH 5.0, enzymatic treatment time of 93 min and a liquid/material ratio of 29:1 mL/g, which correlated well with the predicted yield of 15.58%. Subsequently, the crude LEPs were further purified by DEAE-cellulose and Sephadex-100 chromatography to obtain two fractions, which were designated as LEP-1 and LEP-2 and their monosaccharide compositions were characterized by GC. Fourier-transform infrared spectra demonstrated that LEP-1 and LEP-2 were distinct from each other regarding their chemical structures. In addition, the LEPs exhibited inhibition of cell proliferation on HCT-116 and HeLa cells in vitro . In summary, this study provides an efficient enzyme-assisted extraction for LEPs, which can be used as natural antitumor agents in the pharmaceutical and functional food industries. [ABSTRACT FROM AUTHOR]

Plant-derived monoterpene indole alkaloids (MIAs) from Uncaria rhynchophylla (UR) have huge medicinal properties in treating Alzheimer's disease, Parkinson's disease, and depression. Although many bioactive UR-MIA products have been isolated as drugs, their biosynthetic pathway remains largely unexplored. In this study, untargeted metabolome identified 79 MIA features in UR tissues (leaf, branch stem, hook stem, and stem), of which 30 MIAs were differentially accumulated among different tissues. Short time series expression analysis captured 58 pathway genes and 12 hub regulators responsible for UR-MIA biosynthesis and regulation, which were strong links with main UR-MIA features. Coexpression networks further pointed to two strictosidine synthases (UrSTR1/5) that were coregulated with multiple MIA-related genes and highly correlated with UR-MIA features (r > 0.7, P < 0.005). Both UrSTR1/5 catalyzed the formation of strictosidine with tryptamine and secologanin as substrates, highlighting the importance of key residues (UrSTR1 : Glu309, Tyr155; UrSTR5 : Glu295, Tyr141). Further, overexpression of UrSTR1/5 in UR hairy roots constitutively increased the biosynthesis of bioactive UR-MIAs (rhynchophylline, isorhynchophylline, corynoxeine, etc), whereas RNAi of UrSTR1/5 significantly decreased UR-MIA biosynthesis. Collectively, our work not only provides candidates for reconstituting the biosynthesis of bioactive UR-MIAs in heterologous hosts but also highlights a powerful strategy for mining natural product biosynthesis in medicinal plants. [ABSTRACT FROM AUTHOR]

Due to the versatility of load bearing and heat insulation, foam-filled composite corrugated sandwich plates have a broad application in aerospace industry as thermal insulation structures for hypersonic vehicles. In this paper, a C 0 higher-order layerwise finite element model is presented for aeroelastic analysis of foam-filled composite corrugated sandwich plates in supersonic flow with equivalent properties. The homogenization method for the foam-filled corrugated core is formulated by force and energy equivalence under different assumptions of force or moment distributions. In the proposed layerwise model, the composite sandwich plate is divided into three sections through thickness, while a higher-order displacement field is assumed for the single-layer orthotropic core section and a first-order displacement field for the two face-sheet sections made of multi-layer laminates. The effect of transverse normal strain is also taken into consideration. The unsteady aerodynamic pressure is evaluated by the first-order Piston theory. An eight-noded isoparametric element with 16 degrees of freedom per node is used for finite element method. The accuracy of the present model is verified with existing results in the literature. The influence of geometric parameters and material properties on critical dynamic pressure are discussed. [ABSTRACT FROM AUTHOR]

Abstract: 1,1-Dichloro-2,2 bis(p-chlorophenyl) ethylene (p,p′-DDE), the major metabolite of 2,2-bis(4-chlorophenyl)-1,1,1-trichloroethane (DDT), is a known persistent organic pollutant and male reproductive toxicant. It has antiandrogenic effect. However, the mechanism by which p,p′-DDE exposure causes male reproductive toxicity remains unknown. To elucidate the mechanism underpinning the testicular effects of p,p′-DDE, we sought to investigate Fas/FasL apoptotic pathway in the testis of prepubertal rats, including Fas, FasL, caspase-8, -3, and NF-κB. Animals were administered with different doses of p,p′-DDE (0, 20, 60, 100mg/kg b.wt) every other day by intraperitoneal injection for 10 days. The results indicated that p,p′-DDE exposure at over 20mg/kg b.wt showed the induction of apoptotic cell death. p,p′-DDE could induce increase in the MDA level, and decrease in SOD and GSH-Px activity. Significant elevations in the mRNA levels of Fas along with an increase in FasL, caspase-3, -8 were observed in 100mg/kg b.wt group. In protein level, p,p′-DDE could induce increase of FasL and reduction of procaspase-8. NF-κB p65 was activated by p,p′-DDE treatment in rat testis. In addition, the activities of caspase-3, -8 were increased in 100mg/kg b.wt group. Taken together, these results lead us to speculate that in vivo exposure to p,p′-DDE might induce testicular apoptosis in prepubertal rats through the Fas/FasL pathway. [Copyright &y& Elsevier]