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Obstructive sleep apnea (OSA) is a sleep disorder that may lead to cognitive impairment. The primary pathophysiological feature of OSA is chronic intermittent hypoxia (CIH), but the underlying mechanisms of CIH are not known. There have been few studies on the role of ferroptosis, a novel form of programmed cell death, during CIH-induced cognitive impairment. Therefore, this paper examined ferroptosis' effect on CIH-mediated cognitive impairment.The study randomized twenty-four Sprague-Dawley (SD) male rats to control or CIH group. CIH rats were subjected to intermittent hypoxia for 4 weeks. Rat learning and memory were analyzed by the Morris water maze (MWM) test. Alterations of hippocampal neuronal ultrastructure were observed by transmission electron microscopy (TEM). Malondialdehyde (MDA) and ferrous iron (FeThe MWM test indicated that rats in the CIH group exhibited neurocognitive impairment. TEM showed that CIH induced mitochondrial damage. Significant increases in FeFerroptosis had an essential effect on CIH-mediated cognitive impairment, and it may occur via Nrf2 dysregulation. These findings lay a solid foundation for the subsequent study of OSA-associated cognitive impairment offering potential evidence for the development of therapeutic strategies.

Three new triterpene saponins, mandshunosides C–E ( 1 – 3 ) together with four known triterpene saponins ( 4 – 7 ) were isolated from the roots and rhizomes of Clematis mandshurica . Their structures were elucidated on the basis of spectroscopic evidence and hydrolysis products. Those compounds showed inhibitory activities against two human colorectal cancer cell lines HCT-116 and HT-29.

In order to extract the fault feature validity in early fault diagnosis, method based on kernel principal component analysis and genetic programming (GP) is presented. The time domain features of the vibration signal are extracted and the initial symptom parameters (SP) are constructed. Then the combination to the initial SPs is carried on to optimize and build composite characteristics by GP. Through kernel principal component analysis (KPCA), the nonlinear principal component of the original characteristics is produced. Finally, the nonlinear principal components are selected as the feature subspace to classify the conditions of rolling bearing. Meanwhile, the within-class and among-class distance is introduced to compare and analyze the bearing condition recognition effect by using KPCA and GP plus KPCA separately. Experimental results show that the features extracted by kernel principal component analysis and genetic programming perform better ability in identifying the working states of the rolling bearing.

Ethnopharmacological relevance Aconitum carmichaelii Debx. (Fuzi in Chinese) has been widely clinically used to treat heart failure and rheumatism. Whereas its serious toxicity, Radix et Rhizoma Glycyrrhizae (Gancao in Chinese) was combined with it as traditional Chinese medicine (TCM) herb-pair for toxicity reduction and pharmacological effect improvement. Though some previous viewpoints about that has been reported, the underlying interaction mechanism of two herbs remain unknown and definitely worthy of investigating. Aim of study In present study, we focus on Fuzi–Gancao herb-pair precipitation (FGP), considering it related to the compatibility mechanism of Fuzi–Gancao herb-pair. The intestinal absorption and pharmacokinetic characters of 3 diester diterpenoid alkaloids in the precipitation were investigated. Materials and methods Both everted gut sac model and in situ single-pass intestinal perfusion model were used to investigate rat small intestinal permeability and transport mechanism of aconitine, hypaconitine and mesaconitine. Moreover, by means of determination of the plasma concentration, the pharmacokinetic characters of 3 alkaloid compounds in rats have been developed. Results In everted gut sac permeability experiment, the permeability of hypaconitine appeared best in ileum. Furthermore, their uptakes were increased in the presence of P-glycoprotein (P-gp) inhibitors. In situ single-pass intestinal perfusion uptake experiment, results revealed that the transport mechanism may fit the active transport mechanism. And 3 alkaloids in FPG could be absorbed well in rats, fitting 2-compartment model with 1st order absorption and lag time. Conclusions Our results in present study indicated that 3 diester diterpenoid alkaloids in FGP could be dissolved out in gastrointestinal tract firstly and then absorbed in blood after oral administration, which could result in prolonging their mean residence time and adding their absorbed doses, avoiding dose dumping. The current study has significant enlightenments for further investigation on the interaction mechanisms of other acid-base herb-pairs as well as Fuzi–Gancao herb-pair.

Selective localization of carbon black (CB) at the interface of polymer blends was achieved by the method that EBA-g-MAH was first reacted with CB, and then blended with poly(ethylene-co-butyl acrylate)/nylon6 (EBA/PA6). In CB-filled EBA/PA6 blends, EBA and PA6 phases formed cocontinuous morphology and CB was localized in PA6 phase. The percolation threshold was 5 wt%. A single PTC (positive temperature coefficient) effect was observed in this composite. The appearance of PTC effect was originated from the thermal expansion of EBA phase. In the EBA-g-MAH filled EBA/PA6 blends, TEM results showed that CB particles were induced by EBA-g-MAH to localize at the interface, resulting that the percolation threshold was much lower than that of EBA/PA6/CB. Influence of morphology on PTC effect of EBA/PA6/EBA-g-MAH/CB composites was studied. In the composites with sea-island morphology, the conductive network was fabricated by dispersed phase and CB at the interface. Thermal expansion of matrix interrupted the contact of dispersed phases and conductive network formed by CB particles at the interface, resulting in the double PTC effect. The composites with co-continuous morphology exhibited single PTC effect due to the fact that conductive network was only fabricated by CB localized at the interface. POLYM. ENG. SCI., 53:2640–2649, 2013. © 2013 Society of Plastics Engineers

Three different types of thermoplastics, poly(ether imide) (PEI), polycarbonate (PC), and poly(butylene terephthalate) (PBT) were used to modify epoxy for cryogenic applications. Carbon fiber reinforced thermoplastic modified epoxy composites were also prepared through vacuum-assisted resin transfer molding (RTM). Dynamic mechanical analysis (DMA) shows that the storage moduli of PEI, PC, and PBT modified epoxies are 30%, 21%, and 17% higher than that of the neat epoxy respectively. The impact strength of the modified epoxies at cryogenic temperature increases with increasing thermoplastic content up to 1.5 wt.% and then decreases for further loading (2.0 wt.%). The coefficient of thermal expansion (CTE) values of the PBT, PEI, and PC modified epoxies also decreased by 17.76%, 25.42%, and 30.15%, respectively, as compared with that of the neat epoxy. Optical microscopy image analysis suggests that the presence of PEI and PC in the carbon fiber reinforced epoxy composites can prevent the formation of micro-cracks. Therefore, both the PEI and PC were very effective in preventing micro-crack formation in the composites during thermal cycles at cryogenic condition due to their low CTE values and high impact strength.

Three new triterpene saponins, ilexsaponins D-F (1-3), were isolated from the roots of Ilex pubescens. Their structures were elucidated as 3-O-β-D-glucopyranosyl(1 → 3)-α-L-arabinopyranosyl urs-12,18-diene-24,28-dioic acid 28-O-β-D-glucopyranoside (1), 3-O-β-D-glucopyranosyl(1 → 3)-α-L-arabinopyranosyl urs-12,18-diene-24,28-dioic acid (2), and 3-O-β-D-glucopyranosyl(1 → 3)-α-L-arabinoyranosyl-30-hydroxyurs-12,19-diene-24,28-dioic acid 28-O-β-D-glucopyranoside (3) on the basis of the chemical and spectroscopic evidence.

Selective localization of carbon black (CB) at the interface of polymer blends was achieved by the method that poly(styrene-co-maleic anhydride) (SMA) was first reacted with CB, and then blended with nylon6/polystyrene (PA6/PS). In the PA6/PS blends, CB was localized in PA6 phase and typical double percolation was exhibited. In the PA6/PS/(SMA–CB) blends, TEM results showed that CB particles were induced by SMA to localize at the interface, resulting in the especial interface morphology fabricated by SMA and CB. The especial interface morphology of PA6/PS/(SMA–CB) caused distinct triple percolation behavior and very low percolation threshold. The positive temperature coefficient (PTC) intensity of PA6/PS/(SMA–CB) composites was stronger than that of PA6/PS/CB and the negative temperature coefficient (NTC) effect was eliminated. The elimination of NTC effect was arisen from the especial interface morphology. A stronger PTC intensity was attributed to the low percolation threshold and the morphology.

Novel interpenetrating polymer networks (IPNs) of Polydicyclopentadiene/Polystyrene (PDCPD/PS) were prepared by in-situ polymerization using Ziegler-Natta and peroxide as double catalytic systems. The structure of PDCPD/PS alloy was characterized by Soxhlet extraction, infrared spectrum (IR) and scanning electron microscope (SEM). The results showed that the polymerization of dicyclopentadiene (DCPD) was facilitated in the presence of styrene and the rate of polymerization as well as the conversion of PDCPD was improved with styrene content. The strong IR absorption peaks of PS indicated high penetration of PS within PDCPD networks, and in the process forming IPNs. There were no obvious traces of PS in the alloy brittle fracture, which prepared in liquid nitrogen and was etched by toluene. This result also demonstrated that PS was dispersed in molecular level in the polymer alloy networks and it tangled with PDCPD. The measurements mechanical properties showed that the tensile strength of the polymer alloy was improved with styrene content. This may be due to homogeneous dispersion of PS in the IPNs. The synergistic effect of PS and PDCPD also played a part in enhancing the mechanical properties of polymer alloy.

Polydicyclopentadiene (PDCPD) is a kind of engineering plastic which possesses excellent mechanical performance. It can be made by dicyclopentadiene (DCPD) through Ring-opening metathesis polymerization. In this paper, a supported catalyst of WCl6-phenol on montmorillionite (MMt) was prepared, formed a high efficienct, low-cost and more stable in air, tagether with Et2AlCl as activator, to polymerize the DCPD monomer through ring-opening metathesis polymerization mechanism, and obtained a Polydicyclopentadiene/MMt Nanocomposites. The Molding of PDCPD was finally made by Gusmer-decker’s RIMcell Lt Machine, and the products were characterized by X-ray diffraction, TEM, TGA, SEM, DMA. Mechanical properties were also measured. The result showed that the supported catalyst had good catalytic activity in polymerizing DCPD. MMt was exfoliated in the matrix after the in-situ polymerization, according to the XRD and TEM, which brought about improved properties of PDCPD with small amount MMt dispersed in the matrix.

To investigate the effects of oxygen concentration and reactive oxygen species (ROS) on the biological characteristics of hematopoietic stem cells (HSC) and to analyzed the relationship among the oxygen concentration, ROS and the biological characteristics of mouse HSC through simulation of oxygen environment experienced by PB HSC during transplantation.The detection of reactive oxygen species (ROS), in vitro amplification, directional differentiation (BFU-E, CFU-GM, CFU-Mix), homing of adhesion molecules (CXCR4, CD44, VLA4, VLA5, P-selectin), migration rate, CFU-S of NOD/SCID mice irradiated with sublethal dose were performed to study the effect of oxgen concentration and reactive oxygen species on the biological characteristics of mouse BM-HSC and the relationship among them.The oxygen concentrations lower than normal oxygen concentration (especially hypoxic oxygen environment) could reduce ROS level and amplify more Lin(-) c-kit(+) Sca-1(+) BM HSC, which was more helpful to the growth of various colonies (BFU-E, CFU-GM, CFU-Mix) and to maintain the migratory ability of HSC, thus promoting CFU-S growth significantly after the transplantation of HSC in NOD/SCID mice irradiated by a sublethal dose. BM HSC exposed to oxygen environments of normal, inconstant oxygen level and strenuously thanging of oxygen concentration could result in higher level of ROS, at the same time, the above-mentioned features and functional indicators were relatively lower.The ROS levels of BM HSC in PB HSCT are closely related to the concentrations and stability of oxygen surrounding the cells. High oxygen concentration results in an high level of ROS, which is not helpful to maintain the biological characteristics of BM HSC. Before transplantation and in vitro amplification, the application of antioxidancs and constant oxygen level environments may be beneficial for transplantation of BMMSC.

To analyze the screening of prescription for the total coumarins of Angelica dahurica var. formosana sustained release tablets, and to preliminarily discuss the releasing mechanism.On the basis of orthogonal test data, the prescriptions were screened and optimized by adopting the artificial neural network technology and by taking the in vitro release rate at the setting time as the evaluation indicator.The in vitro release performance of sustained release tablets prepared by the screened optimal technology was good, and the drugs released continuously for 12 h. The drug release process was fitted by adopting the Ritger-Peppas equation. The release of these tablets in artificial gastric juice could be described as the combined action of diffusion and skeleton dissolution.Artificial neural network technology can be used to design the pharmacy prescription, optimize the process, solve nonlinear problems with multiple factors and multiple levels, and reduce the experimental workload. So it has broad application prospect.

Two new triterpenesaponins, ilexsaponins G and H (1 and 2), together with six known triterpenesaponins (3–8), were isolated from the roots of Ilex pubescens. Their structures were elucidated on the basis of spectroscopic evidence and hydrolysis products. Those compounds showed inhibitory activities against two human colorectal cancer cell lines HCT 116 and HT-29.

Iterated Function System (IFS) is an important branch of fractal theory and application. There has not been an effective method to find a given IFS attractor boundary. This paper gives some concepts about Inner Boundary and Inner Splitting Map, and then puts forward “Inner Boundary Filter” algorithm for fast and accurate determination of the spatial boundary of IFS attractor. The algorithm can reach any given precision, with less computing resources. The open problem inherent in IFS theory and application is thus resolved.

The transferring modified lipid coated PLGA nanoparticles, as a targetable vector, were developed for the targeting delivery of anticancer drugs with paclitaxel (PTX) as a model drug to the ovarian carcinoma, which combines the advantages and avoids disadvantages of polymeric nanoparticles and liposomes in drug delivery. A transmission electron microscopy (TEM) confirmed the lipid coating on the polymeric core. Physicochemical characterizations of TFLPs, such as particle size, zeta potential, morphology, encapsulation efficiency, and in vitro PTX release, were also evaluated. In the cellular uptake study, the TFLPs were more efficiently endocytosed by the A2780 cells with high expression of transferrin receptors than HUVEC cells without the transferrin receptors. Furthermore, the anticancer efficacy of TFLPs on the tumor spheroids was stronger than that of lipid coated PLGA nanoparticles (LPs) and PLGA nanoparticles. In the in vivo study, the TFLPs showed the best inhibition effect of the tumor growth for the ovarian carcinoma-bearing mice. In brief, the TFLPs were proved to be an efficient targeting drug delivery system for ovarian carcinoma.

This paper aims to investigate the portal-vein absorption kinetics of berberine in rat, and the influence of P-gp inhibitors such as verapamil and borneol, to its absorption ability. In the paper, a validated UHPLC method was established to determine the berberine in plasma, and the portal-vein absorption model was applied to conduct the pharmacokinetic study. Animals were divided into four groups as follow: group berberine group (BG); group verapamil + berberine group (VBG); group borneol + berberine group (BBG) and group long-term use of borneol + berberine group (LBBG). Plasma samples were obtained at regular time intervals after administration and separated on Agilent 1290 Infinity UHPLC instrument. The method showed good linearity (r = 0.9988) over wide dynamic ranges (4.08–163.20 ng/mL). Variations within- and between-batch never exceeded 7.58 and 2.21 %, respectively. The extraction recovery rates ranged from 85.34 to 111.62 %. We discovered that the AUC of four group exhibited no significant differences (P > 0.05), and co-administration of berberine with borneol of group BBG and group LBBG in advance could both reduce the T max and C max as compared to group BG (P

This study purposed to investigate the effects of different oxygen concentrations and reactive oxygen species (ROS) on the biological characteristics of hematopoietic stem cells (HSC) and their possible mechanisms through simulating oxygen environment to which the peripheral blood HSC are subjected in peripheral blood HSCT. The proliferation ability, cell cycle, directed differentiation ability, ROS level and hematopoietic reconstitution ability of Lin(-)c-kit(+)Sca-1(+) BMHSC were detected by using in vitro amplification test, directional differentiation test, cell cycle analysis, ROS assay and transplantation of Lin(-)c-kit(+)Sca-1(+) HSC from sublethally irradiated mice respectively. The results showed that oxygen concentrations lower than normal oxygen concentration, especially in hypoxic oxygen environment, could reduce ROS generation and amplify more primitive CD34(+)AC133(+) HSC and active CD34(+) HSC, and maintain more stem cells in the G(0)/G(1) phase, which is more helpful to the growth of CFU-S and viability of mice. At the same time, BMHSC exposed to normal oxygen level or inconstant and greatly changed oxygen concentrations could produce a high level of ROS, and the above-mentioned features and functional indicators are relatively low. It is concluded that ROS levels of HSC in BMHSCT are closely related with the oxygen concentration surrounding the cells and its stability. Low oxygen concentration and antioxidant intervention are helpful to transplantation of BMHSC.

Two new triterpene saponins, mandshunosides A and B (1 and 2), were isolated from the roots and rhizomes of Clematis mandshurica. Their structures were elucidated on the basis of spectroscopic evidence and hydrolysis products. Compounds 1 and 2 showed inhibitory activities against two colorectal human cancer cells HCT 116 (IC50 2.1 μM for 1 and 2.5 μM for 2) and HT-29 (IC50 3.7 μM for 1 and 3.3 μM for 2).

The crystal of the title compound, C13H12N2O6, contains a bifurcated intramolecular hydrogen bond between the N—H group and one of the O atoms from both the nitro group and the dioxane-4,6-dione moiety. In addition, molecules are linked by a series of intermolecular C—H...O secondary interactions. The dihedral angles between the benzene ring and the nitro group and the conjugated part of the dioxane-4,6-dione moiety are 19.1 (2) and 17.89 (7)°, respectively.

To study the chemical constituents of the flowers of Bupleurum chinese.The compounds were separated by column chromatography with silica gel. Their structures were identified by spectral methods and chemical analysis.Five compounds were isolated and identified as 8-(3',6'-dimethoxy)-4,5-cyclohexadiene-(delta11,12-dioxide-methylene) -dense-dihydrogen-isocoumarin(I), quercetin(II), rutin(III), calcifenol (IV), isorhamnetin (V).Compounds I and IV are obtained from the genus for the first time. Compound I is a new compound.

In this article an optimum design of optical waveguide modulator in a fin line is given using the spectral-domain method and the spectral-domain immittance approach. It takes into account the thickness of the lithium niobate (LiNbO3) plate, the width of the slot, and the position of the optical waveguide. An example at 3-cm wave band is given. © 1995 John Wiley & Sons. Inc.

In the title compound, C17H21N3O4S2, an intramolecular N—H...O hydrogen bond involving the proximate amine and nitro groups is observed. In the crystal, intermolecular N—H...O hydrogen bonds involving the amine and SO2 groups occur. One of the notro O atoms is disordered over two conformations with occupancies of 0.578 (12) and 0.422 (12).

In the title compound, C15H13NO4, the conjugated double-bond system between the two rings adopts a cis configuration and there is an intramolecular indole–ketone C—H...O interaction. The indole N—H group forms an intermolecular hydrogen bond with a ketone O-atom acceptor, giving a chain structure along the ab direction. The O-heterocyclic ring adopts a boat conformation and makes a dihedral angle of 16.72 (6)° with the indole ring system.