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BPC 157, a pentadecapeptide with extensive healing effects, has recently been suggested to contribute to angiogenesis. However, the underlying mechanism is not yet clear. The present study aimed to explore the potential therapeutic effect and pro-angiogenic mechanism of BPC 157. As demonstrated by the chick chorioallantoic membrane (CAM) assay and endothelial tube formation assay, BPC 157 could increase the vessel density both in vivo and in vitro, respectively. BPC 157 could also accelerate the recovery of blood flow in the ischemic muscle of the rat hind limb as detected by laser Doppler scanning, indicating the promotion of angiogenesis. Histological analysis of the hind limb muscle confirmed the increased number of vessels and the enhanced vascular expression of vascular endothelial growth factor receptor 2 (VEGFR2) in rat with BPC 157 treatment. In vitro study using human vascular endothelial cells further confirmed the increased mRNA and protein expressions of VEGFR2 but not VEGF-A by BPC 157. In addition, BPC 157 could promote VEGFR2 internalization in vascular endothelial cells which was blocked in the presence of dynasore, an inhibitor of endocytosis. BPC 157 time dependently activated the VEGFR2-Akt-eNOS signaling pathway which could also be suppressed by dynasore. The increase of endothelial tube formation induced by BPC 157 was also inhibited by dynasore. This study demonstrates the pro-angiogenic effects of BPC 157 that is associated with the increased expression, internalization of VEGFR2, and the activation of VEGFR2-Akt-eNOS signaling pathway. BPC 157 promotes angiogenesis in CAM assay and tube formation assay. BPC 157 accelerates the blood flow recovery and vessel number in rats with hind limb ischemia. BPC 157 up-regulates VEGFR2 expression in rats with hind limb ischemia and endothelial cell culture. BPC 157 promotes VEGFR2 internalization in association with VEGFR2-Akt-eNOS activation.BPC 157 promotes angiogenesis in CAM assay and tube formation assay. BPC 157 accelerates the blood flow recovery and vessel number in rats with hind limb ischemia. BPC 157 up-regulates VEGFR2 expression in rats with hind limb ischemia and endothelial cell culture. BPC 157 promotes VEGFR2 internalization in association with VEGFR2-Akt-eNOS activation.

Aim To assess the efficacy of intranasal corticosteroid therapy in the treatment of obstructive sleep apnea (OSA) based on current evidence. Methods A number of medical literature data bases: PubMed, Cochrane Library, Scopus, and CINAHL, were searched comprehensively to identify randomized controlled trials (RCT) that reported on the efficacy of intranasal corticosteroid therapy for OSA. The selected studies were subjected to a meta-analysis and a risk-of-bias assessment. Results Seven RCTs met our eligibility criteria, five of these were included in our meta-analysis. The results indicated that intranasal corticosteroid therapy has a better effect in decreasing the apnea-hypopnea index compared with those participants who received placebo (standard mean difference 0.95 [95% confidence interval, -1.42 to -0.47]) (n = 221, I2 = 62%). Conclusion Our study results showed that patients who received intranasal corticosteroid therapy had a significant improvement in OSA. However, this evidence was limited by the potential risk of bias and heterogeneity of the selected RCTs.

Vinyl chloride (VC) workers are known to be at risk for development of angiosarcoma of the liver (ASL), a rare tumor. Previously, a study of p53 gene mutations in tumors of VC-exposed workers found that 50% of liver angiosarcomas contained such mutations. Mutant p53 oncoprotein and anti-p53 antibodies can also be found in the sera of ASL patients and VC-exposed workers without cancer. Workers in Taiwan have also been exposed to VC, and some have contracted liver tumors. In this study, we used enzyme-linked immunosorbent assays to detect mutant p53 protein and anti-p53 antibodies in the plasma of VC-exposed workers in Taiwan. Thirty-three of 251 (13.2%) VC-workers tested positive for the p53 overexpression (10% with positive mutant p53 protein and 3.6% with positive anti-p53) in their plasma, but only 2 of 36 controls (5.6%) tested positive (2.8% with positive mutant p53 protein and 2.8% with positive anti-p53). There was a significant association between cumulative VC exposure concentration and positive p53 expression (P = 0.032) among VC workers after we adjusted for age, hepatitis, drinking, and smoking status. In summary, P53 overexpression (mutant p53 protein or anti-p53 antibody) can be found in the plasma of VC workers in Taiwan, and a significant dose-response relationship exists between plasma p53 overexpression and VC cumulative exposure concentration.

A biplane grid with a mesh spacing of 10.8 cm was towed horizontally in a towing tank to generate turbulence in a non-stratified fluid and in stratified fluids with different constant density gradients. Turbulence velocity components and density fluctuations were measured using an array of cross-film and conductivity probes. Based on the mesh size of the grid, the nominal values of the (internal) Froude numbers were ∞, 80 and 40, and the corresponding Reynolds number was 4.3 × 104. The decay rates of the (turbulence) kinetic, potential and total energies and the dissipation rates of the kinetic and potential energies were calculated from the experimental data. For each of these quantities, the decay may be represented as a function of the downstream distance raised to a given power. The kinetic energy and its dissipation rate are lower for the stratified cases than for the non-stratified case but are almost compensated for by the corresponding potential energy and its dissipation rate. Our results are consistent with those of direct numerical simulations and agree reasonably well with those obtained in stratified wind and water tunnels. However, the results differ from laboratory results obtained using an optical method to measure the turbulent motion of tracer particles in the wake of a vertically towed grid; these latter results show an abrupt reduction in the decay rate of the turbulence kinetic energy after one Brunt–Väisälä period. A similar trend is also observed in results obtained in facilities with fairly high background turbulence or internal waves. This discrepancy is discussed and an explanation is presented. Furthermore, it is demonstrated that strongly stratified thin sheets with density gradients larger than that of the undisturbed fluid may be generated by local but incomplete mixing. The persistence of such thin sheets is proportional to the Schmidt number (≈ 500) in stratified salt water or the Prandtl number (≈ 0.71) in thermally stratified air.

Vinyl chloride (VC) workers are known to be at risk for development of liver angiosarcoma, a rare tumor. Previously, more than 80% of VC workers with liver angiosarcoma have been found to have an Asp-13 c-Ki-ras oncogene mutation, and more than 50% of VC-exposed workers without liver tumors were found to have Asp13-Ki-ras oncoprotein in their plasma. Some workers in Taiwan had also been exposed to VC, and some have contracted liver tumors. In this study, we used enhanced chemiluminescence Western blotting to detect Asp13-p21-Ki-ras in the sera of VC-exposed workers in Taiwan. There were 14 of 113 (12.4%) VC workers positive for the Asp13-Ki-ras oncoprotein in plasma, but 0 of 18 controls were positive. There were 10 of 69 (14.5%) plasma-positives among the more highly exposed (> 1000 ppm-months) workers and 4 of 48 (9.1%) plasma-positives among the lesser exposed (< or = 1000 ppm-months). Compared with the unexposed controls, the odds ratios (and 95% confidence intervals [CI]) for plasma-positivity were 4.11 (95% CI = 0.21, 80.4) in the lower-exposed workers and 6.53 (95% CI = 0.37, 116.9) in the higher-exposed workers, and there was a linear trend between exposure and plasma-positivity (P = 0.073). After adjusting for age and drinking status, the odds ratios (and 95% CIs) were 1.64 (95% CI = 0.17, 15.8), and 2.65 (95% CI = 0.42, 16.8), respectively, and there was a significant linear trend between exposure and plasma-positivity (P = 0.048). In summary, Asp13-Ki-ras oncoprotein can be found in the plasma of VC workers in Taiwan, and a significant dose-response relationship exists between plasma oncoprotein expression and VC exposure.

Displacements of wind waves in the laboratory were measured with a laser displacement gauge, a recent,ly developed, optical, non-intrusive sensor, which avoids the meniscus effect's that severely limit the frequency response of conventional thin- wire gauges. The new gauge is a digital device, which has a maximum frequency response of 2.5 kHz. Its spatial resolution, which depends on the field of view, is t,ypically 0.016 cm for a 4 cm field of view. The wind-wave displacements were measured at several fetches for three wind speeds. Wave-variance spectra derived from these measurements indicate the presence of a quasi-equilibrium spectrum in the capillary-wave regime. The quasi-equilibrium spectrum follows an $f^{-\frac{7}{3}}$ power law that has been predicted on dimensional grounds. The spect'ral density increases with increasing wind speed from 4 to 10 m/s but is independent of the fetch from 3 to 5 m. In addition, the capillary-wave spectrum is practically unchanged when a, relatively long but. low-amplitude mechanical wave is superposed onto the wind- generat'cd waves.

Laboratory experiments were performed to investigate the effects of an oil slick on ocean waves. This is part of an integrated program aimed at understanding the vertical dispersion of oil in the upper ocean. The experiments were conducted in a wind-wave tank which measured 9.1 m long, 1.2 m wide, and 1.8 m deep. Both wind waves and mechanically-generated waves with wind were considered. No. 2 Diesel oil was fed at a rate of 0.35 liters/sec onto the water surface from the upstream end of the wave tank. To measure the wave profiles, an optical sensor-photodiode wave gauge was developed and is described herein. The effects of an oil slick on wind waves were examined in terms of wave profiles and rms wave amplitudes. For wind waves, the presence of the oil slick damps the waves significantly. The amount of damping increases with the wind speed in the range from U∞ = 4 m/sec to 10 m/sec. At U∞ = 10 m/sec, the oil slick breaks into small lenses. The rms amplitudes of the wind-generated waves increase with the fetch without the oil slick, but they do not change appreciably in the presence of the oil slick. For mechanically-generated waves with wind, wave damping by the oil slick becomes insignificant when the waves are sufficiently steep and wave breaking occurs. Prior to wave breaking, however, steepening of the wave crests due to the presence of the oil slick has been observed occasionally as a result of the reduction in the surface tension by the oil film.

A numerical simulation of the turbulent mass diffusion process from an elevated, continuous point source over a wind-disturbed water surface is described. The diffusion equation, with models for turbulent diffusivities, in the boundary layer over water waves was solved with a successive-over-relaxation finite difference scheme. In the numerical computation, measured quantities of flow conditions such as mean velocities, turbulent intensities and boundary layer thickness were used. To improve computational efficiency, a variable grid system was used. The grid system was designed to expand with the spread of the diffusing plume. The water surface was viewed, in the mean, as a flat surface with influences of the wavy surface implicitly incorporated into the turbulent diffusivities. The diffusivities are functions of the turbulent intensities, the boundary layer thickness, and the scale of the phenomenon. The numerical solutions were compared with experimental results of particle concentration measurements obtained with an optical system ( Liu and Karaki , 1972a) in a wind-water tunnel at Colorado State University. With the net mean convection properly corrected for the effects of the particle fall velocity, streamline displacements in a developing boundary layer, and secondary flow (in the experimental facility), general agreements were observed between numerical solutions and corresponding experimental results.

A new optical system which measures forward-scattered light from small particles to determine mean and fluctuating concentrations in a turbulent shear flow has been developed. The system was designed for wind-tunnel measurements. Mobility of the system was one of the most important design criteria. The relationship between concentration and the system voltage output is found to be linear. The frequency response of the system is adequate for turbulent fluctuation measurements. Signal (DC) attenuation with increasing frequency is found to be small. The focal or sampling volume of the optical probe is of the order of 6.0*10-5 in3 for the instrument described. These characteristics of the optical system are comparable to those of a hot-wire anemometer, which enable comparable measurements of fluctuations of concentration and velocity to be made. Measurements of particle concentrations and fluctuations are especially desirable in studies of turbulent mass diffusion processes.