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The anti-inflammatory and antianemic activities of Angelica sinensis polysaccharide (ASP) isolated from roots of Angelica sinensis (AS) was investigated in a complete Freund's adjuvant (CFA)-induced arthritic rat model. It was observed that serum iron (SI) and total iron binding capacity (TIBC) levels were elevated after 4-week oral administration of ASP. Red blood cell (RBC) count and hemoglobin (Hb) concentrations were ameliorated as well. Moreover, inflammatory cytokines IL-6 and TNF-a were decreased strikingly in CFA-induced arthritic rats after treatment of ASP. Evidence also showed that ASP strongly inhibited hepcidin expression through the Janus kinase/signal transducers and activators of transcription (JAK2/STAT3) pathway. Furthermore, ASP exhibited reduced primary and secondary lesions in adjuvant arthritis, attenuating synovitis and inflammatory joint damage. Data presented in this article collectively indicated that ASP significantly decreased proinflammatory cytokines (TNF-a, IL-6), which might play a crucial role in the CFA-induced arthritic rats, and had a therapeutic effect on adjuvant arthritis in rats. Results of Western blot analysis indicated that ASP inhibited the activation of IL-6/JAK2/STAT3 signaling pathway in the CFA-induced arthritic rats.

A supramolecular gelator based on the bistable [ c 2]daisy chain rotaxane is designed and synthesized. The reversible actuation of the [ c 2]daisy chain renders the formed supramolecular gel with acid/base-responsive switching between gel and monomer solution. The efficient switching process is attributed to the ring-sliding effect of the rotaxane in response to acid/base stimuli. The ring-inhibited hydrogen bonding stacking results in a nearly quantitatively disassembly of the gel network after addition of base which is hard to be realized by traditional heating strategy in hydrogen-bonding-supported gel.

The vortex soliton has gained interest in recent years due to its intriguing potential applications in optical data storage, data processing and other areas. In this work an extensive analysis of characteristic features of the vortex-like soliton in a whispering gallery mode microresonator is carried out within the framework of the (2 + 1)-dimensional Lugiato-Lefever equation. It is found that the external pump field will cause the vortex-like solitons to rotate, and these vortex-like solitons can remain stable after increasing the white noise by 5%. Furthermore, the effects of topological charge, diffraction coefficient and self-focusing/self-defocusing nonlinearity on the properties of the vortex-like soliton in the whispering gallery mode microresonator are investigated. The results show that with the increase in topological charge, the vortex-like solitons will expand and the number of layers will increase. Finally, the breathing behavior is revealed when interaction between two vortex-like solitons occurs. Theoretical studies on vortex-like solitons dynamics indicates that WGM microresonators can serve as a powerful platform for exploring the nonlinear dynamics in optical nonlinear cavities. Our results are beneficial to the understanding of the fundamental dynamics of WGM microresonator solitons and extending their practical applications.

Highly ordered hierarchical macroporous-mesoporous alumina with crystalline walls are synthesized by facial route. The general synthesis strategy is based on a sol–gel process associated with block copolymers as soft templates and polystyrene colloidal crystals as hard template to produce macropore and mesopore structures, respectively. Small-angle XRD, TEM and Nitrogen adsorption and desorption results show that hierarchical macroporous-mesoporous alumina possess highly ordered two-dimensional hexagonal mesostructured and highly ordered face centered cubic macropore arrays structure. The present work reveals that the hierarchical macroporous-mesoporous structure can endure high temperature up to 900 °C. FTIR pyridine adsorption measurements show that the amount of Lewis acid sites provided by hierarchical macroporous-mesoporous alumina is nearly two times more than that for mesoporous alumina, indicating that the open macroporous structure may be in favor of the reactant transfer, and the consequently superior activity. Large surface areas, high thermal stability, uniform pore structures and large amounts of surface Lewis acid sites illustrate that these materials are expected to find wide applications in catalysis realm. The highly ordered hierarchical macroporous-mesoporous alumina with crystalline walls are synthesized by a sol–gel process associated with block copolymers as soft templates and polystyrene colloidal crystals as hard template to produce macropore and mesopore structures, respectively.

In view of single machine to infinite bus system with static synchronous compensator, which is affected by internal and external disturbances, a nonlinear adaptive robust controller is constructed based on the improved dynamic surface control method (IDSC). Compared with the conventional DSC, the sliding mode control is introduced to the dynamic surface design procedure, and the parameter update laws are designed using the uncertainty equivalence criterions. The IDSC method not only reduces the complexity of the controller but also greatly improves the system robustness, speed and accuracy. The derived controller cannot only attenuate the influences of external disturbances against system output, but also has strong robustness to system parameters variance because the damping coefficient is considered in the internal parameter uncertainty. Simulation result reveals that the designed controller can effectively improve the dynamic performances of the power system.

DNA double-strand breaks (DSBs) are highly cytotoxic lesions and pose a major threat to genome stability if not properly repaired. We and others have previously shown that a class of DSB-induced small RNAs (diRNAs) is produced from sequences around DSB sites. DiRNAs are associated with Argonaute (Ago) proteins and play an important role in DSB repair, though the mechanism through which they act remains unclear. Here, we report that the role of diRNAs in DSB repair is restricted to repair by homologous recombination (HR) and that it specifically relies on the effector protein Ago2 in mammalian cells. Interestingly, we show that Ago2 forms a complex with Rad51 and that the interaction is enhanced in cells treated with ionizing radiation. We demonstrate that Rad51 accumulation at DSB sites and HR repair depend on catalytic activity and small RNA-binding capability of Ago2. In contrast, DSB resection as well as RPA and Mre11 loading is unaffected by Ago2 or Dicer depletion, suggesting that Ago2 very likely functions directly in mediating Rad51 accumulation at DSBs. Taken together, our findings suggest that guided by diRNAs, Ago2 can promote Rad51 recruitment and/or retention at DSBs to facilitate repair by HR.

We first reported the role of 5-hydroxymethyl-2-furfural (5-HMF) against hypoxia. Here, we studied the mechanism by using oxygen-dependent degradation domain (ODD)-Luc mice, which are a useful model to probe the stabilization of hypoxia-inducible factor 1α (HIF-1α). Compared with three other compounds that have been reported to have a role in stabilizing HIF-1α, 5-HMF caused stronger bioluminescence, which is indicative of HIF-1α stability in the brain and kidney of ODD-Luc mice. We further demonstrated that the HIF-1α protein accumulated in response to 5-HMF in the brains and kidneys of these mice, as well as in PC12 cells. Additionally, 5-HMF promoted the nuclear translocation of HIF-1α and the transcriptional activity of HIF-1, which was evaluated by detecting vascular endothelial growth factor (VEGF ) mRNA expression. These results suggest that 5-HMF stabilized HIF-1α and increased its activity. Considering the role of proline hydroxylases (PHDs) in negatively regulating HIF-1α stability, we explored whether 5-HMF interacts with the substrates and cofactors of PHDs, such as 2-oxoglutarate (2-OG), Fe(2+) and vitamin C (VC), which affects the activity of PHDs. The result revealed that 5-HMF did not interact with Fe(2+) or 2-OG but interacted with VC. This interaction was confirmed by subsequent experiments, in which 5-HMF entered into cells and reduced the VC content. The enhanced stability of HIF-1α by 5-HMF was reversed by VC supplementation, and the improved survival of mice caused by 5-HMF under hypoxia was abrogated by VC supplementation. Thus, we demonstrated for the first time that 5-HMF increases HIF-1α stability by reducing the VC content, which mediates the protection against hypoxia.

The active-passive hybrid piezoelectric network (APPN) is investigated to reduce the vibration of cantilever beam. Hamilton’s principle with the Rayleigh-Ritz method is used to derive the equations of motion of the beam with the APPN. Only one piezoelectric actuator is bonded on the cantilever beam, so in the segment of the beam where the piezoelectric actuator is attached, the neutral axis is not the geometric center of the beam. This change on the neutral axis is considered in the process of deriving equations. Selecting RL circuit as passive shunt circuit, open-loop analysis is performed to gain insight into the passive damping features. Velocity feedback control is then employed to analyze the characteristics of the closed-loop system. Numerical results show that the APPN has a significant effect on vibration suppression, especially at narrow frequency bands. On this basis, variable RL circuit is proposed and analyzed for broadband vibration attenuation. Numerical simulations illustrate that this scheme is effective and feasible.

Abietane diterpenes and miltirone series have shown important activities and for medical purposes in order to achieve the total synthesis of 1-oxomiltrone 1 and miltirone 4, a versatile intermediate 6 was found. The compound 6 could be used as a precursor A-B-C rings with different oxidative degrees in selected abietane diterpenes when synthesized through high yield Suzuki reaction and subsequent cyclization, and total synthesis of 1-oxomiltirone (1) has been achieved. Electronic Supplementary Material Supplementary material is available for this article at 10.1007/s13659-013-0034-7 and is accessible for authorized users.

Four new labdane-type diterpenoid glycosides, laevissiosides A-D (1–4) were isolated from the 95% ethanol extract of Diplopterygium laevissimum (Christ) Nakai, along with two known analogues, 18- β-D-glucopyranosyl ester-sclareol (5) and 18-hydroxy-sclareol (6). The structures of compounds 1–4 were elucidated by extensive 1D and 2D NMR spectroscopy as well as high-resolution MS analyses. All isolated compounds were evaluated for their cytotoxic effects.

In an attempt to find new types of anti-hypoxic agents from herbs, we identified 5-hydroxymethyl-2-furfural (5-HMF) as a natural agent that fulfills the criterion. 5-HMF, the final product of carbohydrate metabolism, has favorable biological effects such as anti-oxidant activity and inhibiting sickling of red blood cells. The role of 5-HMF in hypoxia, however, is not yet. Our pilot results showed that pretreatment with 5-HMF markedly increased both the survival time and the survival rate of mice under hypoxic stress. The present study was aimed to further investigate the protective role of 5-HMF and the underlying mechanisms in hypoxic injury using ECV304 cells as an in vitro model. ECV304 cells pretreated with or without 5-HMF for 1 h were exposed to hypoxic condition (0.3% O(2)) for 24 h and then cell apoptosis, necrosis, the changes of mitochondrial membrane potential (MMP) and the expressions of phosphorylation- extracellular signal-regulated kinase (p-ERK) were investigated. Pretreatment with 5-HMF markedly attenuated hypoxia-induced cell necrosis and apoptosis at late stage (p 0.01). Furthermore, pretreatment with 5-HMF rescued both the decline of the MMP and the increase of p-ERK protein under hypoxia. In a word, these results indicated that 5-HMF had protective effects against hypoxic injury in ECV304 cells, and its effects on MMP and p-ERK may be involved in the mechanism.

It has been demonstrated that hypoxic preconditioning (HP) enhances the survival ability of the organism against the subsequent acute anoxia (AA). However, it is not yet clear whether necrosis induced by AA can be prevented by HP, and what are the underlying mechanisms. In this study, we examined the effect of HP (10% O(2), 48 h) on necrosis induced by AA (0% O(2), 24 h) in PC12 cells. We found that HP delayed the regulatory volume decrease and reduced cell swelling after 24 h of exposure to AA. Since aldose reductase (AR) is involved in cell volume regulation, we detected AR mRNA expression with reverse transcription-polymerase chain reaction (RT-PCR) techniques. The AR mRNA level was dramatically elevated by HP. Furthermore, an HP-induced decrease in cell injury was reversed by berberine chloride (BB), the inhibitor of AR. In addition, sorbitol synthesized from glucose catalyzed by AR is directly related to cell volume regulation. Subsequently, we tested sorbitol content in the cytoplasm. HP clearly elevated sorbitol content, while BB inhibited the elevation induced by HP. Further study showed that a strong inhibitor of sorbitol permease, quinidine, completely reversed the protection induced by HP after AA. These data provide evidence that HP prevents necrosis induced by AA and is mediated by AR and sorbitol pathway.

An exact augmented Lagrangian function for the nonlinear nonconvex programming problems with inequality constraints was discussed. Under suitable hypotheses, the relationship was established between the local unconstrained minimizers of the augmented Lagrangian function on the space of problem variables and the local minimizers of the original constrained problem. Furthermore, under some assumptions, the relationship was also established between the global solutions of the augmented Lagrangian function on some compact subset of the space of problem variables and the global solutions of the constrained problem. Therefore, from the theoretical point of view, a solution of the inequality constrained problem and the corresponding values of the Lagrange multipliers can be found by the well-known method of multipliers which resort to the unconstrained minimization of the augmented Lagrangian function presented.

Ordered CuIn(1−x)Ga x Se2 (CIGS) nanopore films were prepared by one-step electrodeposition based on porous anodized aluminum oxide templates. The as-grown film shows a highly ordered morphology that reproduces the surface pattern of the substrate. Raman spectroscopy and X-ray diffraction pattern show that CIGS nanopore films had ideal chalcopyrite crystallization. Energy dispersive spectroscopy reveals the Cu-Se phases firstly formed in initial stage of growth. Then, indium and gallium were incorporated in the nanopore films in succession. Cu-Se phase is most likely to act as a growth promoter in the growth progress of CIGS nanopore films. Due to the high surface area and porous structure, this kind of CIGS films could have potential application in light-trapping CIGS solar cells and photoelectrochemical water splitting.

Background The operative treatment of adult degenerative scoliosis combined with osteoporosis increase following the epidemiological development. Studies have confirmed that screws in osteoporotic spines have significant lower-screw strength with more frequent screw movements within the vertebra than normal spines. Screws augmented with Polymethylmethacrylate (PMMA) or with autogenous bone can offer more powerful corrective force and significant advantages. Methods A retrospective analysis was conducted on 31 consecutive patients with degenerative lumbar scoliosis combined with osteoporosis who had surgery from December 2000. All had a minimum of 2-year follow-up. All patients had posterior approach surgery. 14 of them were fixed with pedicle screw by augmentation with Polymethylmethacrylate (PMMA) and the other 17 patients with autogenous bone. Age, sex and whether smoking were similar between the two groups. Surgical time, blood loss, blood transfusion, medical cost, post surgery ICU time, hospital day, length of oral pain medicines taken, Pre-and postoperative Oswestry disability index questionnaire and surgical revision were documented and compared. Preoperative, postoperative and final follow up Cobb angle, sagittal lumbar curve, correction rate, and Follow up Cobb loss were also compared. Results No significant differences were found between the autogenous bone group and Polymethylmethacrylate group with regards to all the targets above except for length of oral pain medicines taken and surgery cost. 2 patients were seen leakage during operation, but there is neither damage of nerve nor symptom after operation. No revision was needed. Conclusion Both augmentation pedicle screw with Polymethylmethacrylate (PMMA) and autogenous bone treating degenerative lumbar scoliosis combined with osteoporosis can achieve a good surgical result. Less oral pain medicines taken are the potential benefits of Polymethylmethacrylate augmentation, but that is at the cost of more medical spending.

Introduction Although immune dysfunction plays a role in the pathogenesis of systemic sclerosis (SSc), involvement of T helper 17 (Th17) and T regulatory (Treg) cells remains unclear. We aimed to investigate the presence of Th17 and Treg cells in SSc patients and the role of Th17 cells in collagen production in SSc fibroblasts. Methods We analyzed inflammatory cell profiles in the skin of 13 SSc patients by immunohistochemistry, the percentage of Th17 and Treg cells in peripheral blood mononuclear cells (PBMCs) of 45 SSc patients and 24 healthy controls by flow cytometry, gene expression in PBMCs by real-time reverse transcription-polymerase chain reaction and interleukin-17 (IL-17) in sera and culture supernatants by enzyme-linked immunosorbent assay. We also investigated the effect of Th17 cell-derived IL-17 on fibroblast growth and collagen production. Results Infiltration of inflammatory cells including IL-17+ and Foxp3+ lymphocytes was detected in the skin of patients with early SSc. The percentages of circulating Th17 cells and IL-17 production were elevated in samples from patients with active SSc, whereas the percentage of circulating Treg cells was not affected. The number of Th17 cells was closely related to disease activity. IL-17 from SSc patients promoted fibroblast growth and collagen production, whereas IL-17 neutralizing antibody effectively blocked collagen production. Conclusion SSc progression might be linked to expansion of circulating Th17 cells and increased infiltration of IL-17+ cells in skin. Th17-derived IL-17 is involved in fibroblast growth and collagen production. IL-17 blocking antibody may be a useful tool for intervention in the fibrotic course of SSc.