Neuroprotective Effects of Citicoline in in Vitro Models of Retinal Neurodegeneration

In recent years, citicoline has been the object of remarkable interest as a possible neuroprotectant. The aim of this study was to investigate if citicoline affected cell survival in primary retinal cultures and if it exerted neuroprotective activity in conditions modeling retinal neurodegeneration. Primary retinal cultures, obtained from rat embryos, were first treated with increasing concentrations of citicoline (up to 1000 μM) and analyzed in terms of apoptosis and caspase activation and characterized by immunocytochemistry to identify neuronal and glial cells. Subsequently, excitotoxic concentration of glutamate or High Glucose-containing cell culture medium (HG) was administered as well-known conditions modeling neurodegeneration. Glutamate or HG treatments were performed in the presence or not of citicoline. Neuronal degeneration was evaluated in terms of apoptosis and loss of synapses. The results showed that citicoline did not cause any damage to the retinal neuroglial population up to 1000 μM. At the concentration of 100 μM, it was able to counteract neuronal cell damage both in glutamate- and HG-treated retinal cultures by decreasing proapoptotic effects and contrasting synapse loss. These data confirm that citicoline can efficiently exert a neuroprotective activity. In addition, the results suggest that primary retinal cultures, under conditions inducing neurodegeneration, may represent a useful system to investigate citicoline neuroprotective mechanisms.     

Clinical symptomatology of coronary artery disease and results of exercise thallium scintigraphy: gender-related differences

Exercise thallium stress test is the mainstay of the noninvasive assessment of patients with symptomatology suggestive of coronary artery disease. The diagnostic accuracy of thallium scintigraphy as a screening test for coronary artery disease in women as compared to men, however, remains controversial. In order to determine whether gender-related differences in the detection of coronary artery disease using exercise thallium scintigraphy are demonstrable in all age groups, we analyzed the exercise thallium results in 335 outpatients (189 male, 146 female), who were referred by their primary physicians to our institution for evaluation of clinically suspected coronary artery disease. Overall, 50.3 percent of men had a positive for ischemia thallium stress test vs 29.5 percent of women (p < 0.0002). In the subgroup of patients 65 years of age or above, 67.4 percent of men had a positive for ischemia thallium stress test vs 27.6 percent of women (p < 0.003). In the subgroup of patients upto 40 years of age, 37.9 percent of men had a positive for ischemia thallium stress test vs 25.0 percent of women (p = NS). We conclude that symptoms suggestive of coronary artery disease are less predictive of positive exercise thallium stress tests in women as compared to men even above age 65 when the prevalence of coronary artery disease is known to be similar. This suggests that women may have lower threshold for perception of symptoms or that physicians have lower threshold for referring women for screening of coronary artery disease.     

Results from the SIFTER (Scintillating Fiber Telescope forEnergetic Radiation) beam test apparatus

The Scintillating Fiber Telescope for Energetic Radiation (SIFTER) is a large-area instrument concept for high-energy (E>10 MeV) gamma-ray astronomy. It takes advantage of the technology of fine (~1 mm ²) plastic scintillating fibers in the context of a pair tracker/calorimeter telescope. In our on-going SIFTER research, we have developed a small test apparatus, consisting of 12 fiber planes, each with a potential active area of 10 cm×10 cm covered with a thin tantalum foil converter. This apparatus was tested in July, 1998 with high-energy photons (~0.5-1.6 GeV) at the Thomas Jefferson National Accelerator Laboratory Hall B tagged gamma-ray facility. We report on results of the beam test, concentrating on comparisons with detailed Monte Carlo simulations of the instrument performance, including track reconstruction, angular resolution and detection efficiency     

Existence of a feedback equilibrium for two-stage Stackelberg games

In this paper we consider a two-stage feedback game in which two players solve a Stackelberg problem at each stage and each player knows the state of the game at every level of play. In this kind of game, the leader does not have the ability to announce his strategy at all levels of play prior to the start of the game. Without assuming that at each stage the Stackelberg problem has a unique solution, we define a concept of “feedback Stackelberg solution” and give sufficient conditions to get existence of such a solution     

EFI:要想保持领先地位必须与时俱进

<正>印刷是一个与众不同的行业,在创新科技迅速发展的今天,如果你想保持领先就要关注与行业相关的最新技术和最新趋势,原地踏步是不可取的。目前,EFI十分关注5件事情:一是自动化。如今各行各业的发展趋势都是自动化,最终目标是"零接触"。现在中国的发展趋势是劳动力成本不断上涨、市场增长十分迅速,焦点转移到高质量产品,因此自动化显得越来越重要。     

Variation in adhesion properties and film morphologies of waterborne pressure-sensitive adhesives containing an acid-rich diblock copolymer additive

One challenge for waterborne pressure-sensitive adhesives (PSA)s is the typical tradeoff between cohesion and adhesion. Others have shown that waterborne PSA films with thin, hard boundaries formed from short poly(acid) segments surrounding soft particles can have simultaneous improvements in adhesion and cohesion. To study this approach in commercial-type acrylic waterborne PSAs, a diblock copolymer (BCP) composed of poly(acrylic acid)-block-(n-butyl acrylate) (PAA-b-PBA) is added at 1–5 wt% to PSAs composed of 100% PBA (PSA (0% acid)) or 99% BA/1% AA (PSA (1% acid)). Films of these blends prepared using industrially relevant conditions reveal complex nanodomains in atomic force microscopy (AFM) images. PSA performance tests showed that 1–2 wt% BCP additive nearly tripled adhesion to stainless steel for PSA (0% acid) while improving cohesion. Nonetheless, AFM images of PSA (0% acid) with 1–2 wt% BCP display ill-defined morphologies, with clear percolated structures apparent primarily in films with 5% BCP. This indicates that film morphologies which enhance adhesion may not correlate with AFM features. Moreover, the balance of adhesion and cohesion of PSA (1% acid) without BCP exceeds that of any of the BCP blends, demonstrating the challenge of using designed microstructures to improve upon conventional PSAs containing copolymerized acids.