39 research outputs found

    Rosiglitazone Restores Endothelial Dysfunction in a Rat Model of Metabolic Syndrome through PPARĪ³- and PPARĪ“-Dependent Phosphorylation of Akt and eNOS

    Get PDF
    Vascular endothelial dysfunction has been demonstrated in metabolic syndrome (MS). Chronic administration of rosiglitazone ameliorates endothelial dysfunction through PPARĪ³-mediated metabolic improvements. Recently, studies suggested that single dose of rosiglitazone also has direct vascular effects, but the mechanisms remain uncertain. Here we established a diet-induced rat model of MS. The impaired vasorelaxation in MS rats was improved by incubating arteries with rosiglitazone for one hour. Importantly, this effect was blocked by either inhibition of PPARĪ³ or PPARĪ“. In cultured endothelial cells, acute treatment with rosiglitazone increased the phosphorylation of Akt and eNOS and the production of NO. These effects were also abolished by inhibition of PPARĪ³, PPARĪ“, or PI3K. In conclusion, rosiglitazone improved endothelial function through both PPARĪ³- and PPARĪ“-mediated phosphorylation of Akt and eNOS, which might help to reconsider the complex effects and clinical applications of rosiglitazone

    Absolute co-supplement and absolute co-coclosed modules

    Get PDF
    A module M is called an absolute co-coclosed (absolute co-supplement) module if whenever M ā‰… T/X the submodule X of T is a coclosed (supplement) submodule of T. Rings for which all modules are absolute co-coclosed (absolute co-supplement) are precisely determined. We also investigate the rings whose (finitely generated) absolute co-supplement modules are projective. We show that a commutative domain R is a Dedekind domain if and only if every submodule of an absolute co-supplement R-module is absolute co-supplement. We also prove that the class Coclosed of all short exact sequences 0ā†’Aā†’Bā†’Cā†’0 such that A is a coclosed submodule of B is a proper class and every extension of an absolute co-coclosed module by an absolute co-coclosed module is absolute co-coclosed.Scientific and Technical Research Council of Turke

    The Ginger-shaped Asteroid 4179 Toutatis: New Observations from a Successful Flyby of Chang'e-2

    Full text link
    On 13 December 2012, Chang'e-2 conducted a successful flyby of the near-Earth asteroid 4179 Toutatis at a closest distance of 770 Ā±\pm 120 meters from the asteroid's surface. The highest-resolution image, with a resolution of better than 3 meters, reveals new discoveries on the asteroid, e.g., a giant basin at the big end, a sharply perpendicular silhouette near the neck region, and direct evidence of boulders and regolith, which suggests that Toutatis may bear a rubble-pile structure. Toutatis' maximum physical length and width are (4.75 Ɨ\times 1.95 km) Ā±\pm10%\%, respectively, and the direction of the +zz axis is estimated to be (250Ā±\pm5āˆ˜^\circ, 63Ā±\pm5āˆ˜^\circ) with respect to the J2000 ecliptic coordinate system. The bifurcated configuration is indicative of a contact binary origin for Toutatis, which is composed of two lobes (head and body). Chang'e-2 observations have significantly improved our understanding of the characteristics, formation, and evolution of asteroids in general.Comment: 21 pages, 3 figures, 1 tabl

    Intra-Articular Injection of Fructus Ligustri Lucidi Extract Attenuates Pain Behavior and Cartilage Degeneration in Mono-Iodoacetate Induced Osteoarthritic Rats

    Get PDF
    Fructus Ligustri Lucidi (FLL) has been widely used as a traditional Chinese medicine (TCM) for treating soreness and weakness of waist and knees. It has potential for treating OA owing to its kidney-tonifying activity with bone-strengthening effects, but there is so far no report of its anti-OA effect. This study established a rat OA model by intra-articular (IA) injection of mono-iodoacetate (1.5 mg) and weekly treated by IA administration of FLL at 100 Ī¼g/mL for 4 weeks. Thermal withdrawal latency, mechanical withdrawal threshold, and spontaneous activity were tested for evaluation of pain behavior, and histopathological (HE, SO, and ABH staining) and immunohistochemical (Col2, Col10, and MMP13) analyses were conducted for observation of cartilage degradation. In vitro effect of FLL on chondrocytes was evaluated by MTT assay and qPCR analysis. Moreover, HPLC analysis was performed to determine its chemoprofile. The pain behavioral data showed that FLL attenuated joint pain hypersensitivity by increasing thresholds of mechanical allodynia and thermal hyperalgesia as well as spontaneous activity. The histopathological result showed that FLL reversed OA cartilage degradation by protecting chondrocytes and extracellular matrix in cartilage, and the immunohistochemical analysis revealed its molecular actions on protein expressions of MMP13, Col2, and Col10 in cartilage. The MTT assay showed its proliferative effects on chondrocytes, and qPCR assay clarified its mechanism associated with gene expressions of Mmp13, Col2, Col10, Adamts5, Aggrecan, and Runx2 in TNF-Ī± treated chondrocytes. Our results revealed an anti-OA effect of FLL on pain behavior and cartilage degradation in OA rats and clarified a molecular mechanism in association with the suppression of chondrocyte hypertrophy and catabolism. IA FLL can be regarded as novel and promising option for OA therapy

    Generating and moving Dirac points in a two-dimensional deformed honeycomb lattice arrayed by coupled semiconductor quantum dots

    No full text
    Analysis of the electronic properties of a two-dimensional (2D) deformed honeycomb structure arrayed by semiconductor quantum dots (QDs) is conducted theoretically by using tight-binding method in the present paper. Through the compressive or tensile deformation of the honeycomb lattice, the variation of energy spectrum has been explored. We show that, the massless Dirac fermions are generated in this adjustable system and the positions of the Dirac cones as well as slope of the linear dispersions could be manipulated. Furthermore, a clear linear correspondence between the distance of movement d (the distance from the Dirac points to the Brillouin zone corners) and the tunable bond angle Ī± of the lattice are found in this artificial planar QD structure. These results provide the theoretical basis for manipulating Dirac fermions and should be very helpful for the fabrication and application of high-mobility semiconductor QD devices

    Effect of Forced Air Cooling on the Microstructures, Tensile Strength, and Hardness Distribution of Dissimilar Friction Stir Welded AA5A06-AA6061 Joints

    No full text
    Friction stir welding (FSW) is a promising welding method for welding dissimilar materials without using welding flux. In the present work, 5A06-H112 and 6061-T651 aluminium alloys were successfully welded by friction stir welding with forced air cooling (FAC) and natural cooling (NC). Nanoindentation tests and microstructure characterisations revealed that forced air cooling, which can accelerate the cooling process and suppress the coarsening of grains and the dissolution of precipitate phases, contributes to strengthening and narrowing the weakest area of the joint. The tensile strength of joints with FAC were commonly improved by 10% compared to those with NC. Scanning electron microscopy (SEM) images of the fracture surface elucidated that FSW with FAC tended to increase the number and reduce the size of the dimples. These results demonstrated the advantages of FSW with FAC in welding heat-sensitive materials and provide fresh insight into welding industries

    The clinical application and advancement of robot-assisted McKeown minimally invasive esophagectomy for esophageal cancer

    No full text
    Robotic surgery systems, as emerging minimally invasive approaches, have been increasingly applied for the treatment of esophageal cancer because they provide a high-definition three-dimensional surgical view and mechanical rotating arms that surpass the limitations of human hands, greatly enhancing the accuracy and flexibility of surgical methods. Robot-assisted McKeown esophagectomy (RAME), a common type of robotic esophagectomy, has been gradually implemented with the aim of reducing postoperative complications, improving postoperative recovery and achieving better long-term survival. Multiple centers worldwide have reported and summarized their experiences with the RAME, and some have also discussed and analyzed its perioperative effects and survival prognosis compared with those of video-assisted minimally invasive esophagectomy. Compared to traditional surgery, the RAME has significant advantages in terms of lymph node dissection although there seems to be no difference in overall survival or disease-free survival. With the continuous advancement of technology and the development of robotic technology, further development and innovation are expected in the RAME field. This review elaborates on the prospects of the application and advancement of the RAME to provide a useful reference for clinical practice
    corecore