No abstract

Excessive proliferation of vascular smooth muscle cells (VSMC) in the intima is an important etiologic factor in vascular proliferative disorders such as atherosclerosis and restenosis after balloon angioplasty. Therefore, control of VSMC growth may be a suitable therapeutic intervention in vascular proliferative disorders. In the present work, we have studied the 2-benzyloxybenzaldehyde (CCY1a)-mediated antiproliferative effect and its mechanisms of action. CCY1a inhibited serum-induced VSMC proliferation in a concentration-dependent manner, as demonstrated using [³H]thymidine incorporation and MTT assays; the IC₅₀ values were calculated to be 7.0 × 10^–6 and 1.2 × 10^–5M, respectively. Furthermore, it also significantly suppressed serum-induced progression of the cell cycle, as shown by flow cytometric analysis. CCY1a as well as PD98059 almost completely abolished serum-induced activation of p42/44 mitogen-activated protein kinase (MAPK), the downstream effectors of c-fos and c-jun mRNA expression and activator protein-1 (AP-1) DNA binding activity, suggesting the central roles of these signaling cascades. Interestingly, CCY1a also effectively blocked serum-induced IĸB-α phosphorylation, IĸB-α degradation and nuclear factor-ĸB (NF-ĸB) binding activity. Based on these observations, we examined the effect of CCY1a on serum-mediated Ras activity, an upstream regulator of the above signaling events. The data demonstrated a marked inhibition of Ras activation by CCY1a. We conclude that CCY1a blocks cell proliferation via inhibition of the upstream effector of Ras and downstream events, including p42/44 MAPK activation and c-fos and c-jun mRNA expression, as well as NF-ĸB and AP-1 DNA binding activities.

Abstract. Video delivery application over wireless network has become increasingly important in recent years. For achieving more flexible video streams transmission, the scalable extension of the H.264/AVC standard has been developed, as well as which is combined with temporal, spatial and quality scalabilities to adapt efficiently the wireless bandwidth resource. In this paper, a cross-layer optimization for robust H.264 scalable video delivery over WiMAX network is proposed. In order to obtain a better delivery performance, the proposed method is used the hierarchical B-picture approach to classify video packets into different priorities. In the cross-layer optimization, the scalable video and packet classifier are proposed at the application layer, and the packet priority and queue allocation are used at the MAC layer. Finally, it is shown by NS2 simulations that the proposed method provides more stable wireless bandwidth and also achieves a better quality of the video streaming delivery.

No abstract

Natural plant extracts without non-toxic side effect and the relevant products are gaining popularity, and make natural medicines one option of health care. This study combines polypropylene (PP) fibers, high-absorption polyacrylate (HPA) fibers with weight ratios of 100/0, 90/10, and 80/20 wt % with a nonwoven manufacturing process to form PP/HPA nonwoven fabrics, after which the fabrics are immersed in a Bletilla striata (BS) extract, and then dried, yielding functional PP/HPA/BS nonwoven fabric. Stereomicroscopic observation, tensile strength test, tear strength test, and air permeability test are performed on the sample to evaluate the difference in mechanical properties before and after the immersion. In vitro test evaluates the biocompatibility of BC extract. The experimental results show that functional PP/HPA/BS nonwoven fabrics have optimal mechanical properties and an optimal content of 32.2 % BS extract when the nonwoven fabrics are made with an 80:20 ratio.