5,830 research outputs found
Cyclosporine augments hepatic regenerative response in rats
A number of mechanisms participate in the hepatic injury that occurs during and following liver transplantation. A normal allograft regenerative response is probably essential for a successful transplant outcome. In this study, the effect of cyclosporine, a potent immunosuppressant used routinely after liver transplantation, on the regenerative response of the liver after partial hepatectomy was investigated. Male Wistar rats were pretreated for one week with either cyclosporine or the olive oil vehicle and were subjected to either a two-thirds partial hepatectomy or a sham operation. Animals were sacrificed at various times postoperatively and the remnant livers were weighed to determine the liver weight to body weight ratio, two biochemical measures of a regenerative response (cytosolic ornithine decarboxylase activity and thymidine kinase activity), and the hepatic content of estrogen and androgen receptors, as the content of these receptors has been shown to modulate, at least in part, the subsequent hepatic regenerative response. The preoperative hepatic cytosol content of ornithine decarboxylase, thymidine kinase, and estrogen receptor was significantly greater (P<0.05) in rats pretreated with cyclosporine than in those treated with the vehicle alone. A significant increase in ornithine decarboxylase and thymidine kinase activities occurred after partial hepatectomy in both the cyclosporine-pretreated and vehicle-pretreated animals. The absolute levels for each parameter were also greater in the cyclosporine-treated animals than in the vehicle-treated controls at 24 hr after partial hepatectomy (P<0.05). The pattern of change in the hepatic cytosolic content of estrogen and androgen receptors in both groups of animals was comparable with those described previously for regenerating liver. These data suggest that cyclosporine may predispose the liver to respond to either a regenerative signal or perceived need and thereby fortuitously enhance liver graft performance after successful surgical implantation. © 1989 Plenum Publishing Corporation
Enhanced Anandamide Plasma Levels in Patients with Complex Regional Pain Syndrome following Traumatic Injury: A Preliminary Report
The complex regional pain syndrome (CRPS) is a disabling neuropathic pain condition that may develop following injuries of the extremities. The pathogenesis of this syndrome is not clear; however, it includes complex interactions between the nervous and the immune system resulting in chronic inflammation, pain and trophic changes. This interaction may be mediated by chronic stress which is thought to activate the endogenous cannabinoid (endocannabinoid) system (ECS). We conducted an open, prospective, comparative clinical study to determine plasma level of the endocannabinoid anandamide by high-performance liquid chromatography and a tandem mass spectrometry system in 10 patients with CRPS type I versus 10 age- and sex-matched healthy controls. As compared to healthy controls, CRPS patients showed significantly higher plasma concentrations of anandamide. These results indicate that the peripheral ECS is activated in CRPS. Further studies are warranted to evaluate the role of the ECS in the limitation of inflammation and pain. Copyright (C) 2009 S. Karger AG, Base
A novel experimental design of a real-time VR tracking device
Virtual Reality (VR) is progressively adopted at different stages of design and product development. Consequently, evolving interaction requirements in engineering design and development for VR are essential for technology adoption. One of these requirements is real-time positional tracking. This paper aims to present an experimental design of a new real-time positional tracking device (tracker), that is more compact than the existing solution, while addressing factors such as wearability and connectivity. We compare the simulation of the proposed device and the existing solution, discuss the results, and the limitations. The new experimental shape of the device is tailored towards research, allowing the engineering designer to take advantage of a new tracker alternative in new ways, and opens the door to new VR applications in research and product development
The Impact of New Polarization Data from Bonn, Mainz and Jefferson Laboratory on Multipoles
New data on pion-photoproduction off the proton have been included in the
partial wave analyses Bonn-Gatchina and SAID and in the dynamical
coupled-channel approach J\"ulich-Bonn. All reproduce the recent new data well:
the double polarization data for E, G, H, P and T in
from ELSA, the beam asymmetry for and
from Jefferson Laboratory, and the precise new differential cross section and
beam asymmetry data for from MAMI. The new fit
results for the multipoles are compared with predictions not taking into
account the new data. The mutual agreement is improved considerably but still
far from being perfect
Geometric and dynamic perspectives on phase-coherent and noncoherent chaos
Statistically distinguishing between phase-coherent and noncoherent chaotic
dynamics from time series is a contemporary problem in nonlinear sciences. In
this work, we propose different measures based on recurrence properties of
recorded trajectories, which characterize the underlying systems from both
geometric and dynamic viewpoints. The potentials of the individual measures for
discriminating phase-coherent and noncoherent chaotic oscillations are
discussed. A detailed numerical analysis is performed for the chaotic R\"ossler
system, which displays both types of chaos as one control parameter is varied,
and the Mackey-Glass system as an example of a time-delay system with
noncoherent chaos. Our results demonstrate that especially geometric measures
from recurrence network analysis are well suited for tracing transitions
between spiral- and screw-type chaos, a common route from phase-coherent to
noncoherent chaos also found in other nonlinear oscillators. A detailed
explanation of the observed behavior in terms of attractor geometry is given.Comment: 12 pages, 13 figure
A preliminary approach for swimming performance analysis of FISDIR elite athletes with intellectual impairment using an inertial sensor
People with intellectual impairment show low performances in motor control, especially in complex movements. Performance analysis methods, based on wearable inertial sensor, are often used in typical developed swimmers but have never been used in swimmers with intellectual impairment, for whom the use of quantitative systems would be even more important. This paper presents a case study conducted on freestyle swimmers from the functional evaluation project of the Italian Sport Federation for athletes with Intellectual Impairment (FISDIR). The tests were conducted by five Italian elite swimmers with intellectual impairment using a structured experimental protocol which foresees an inertial sensor located on the wrist. Key freestyle temporal and kinematic parameters were assessed. A high-speed camera was used as a benchmark to validate the inertial-based parameters. The preliminary results indicate that the proposed inertial-based approach correlates over 90% with the performance indices obtained with the camera-based approach, and therefore it could represent a useful tool for monitoring and improving the training
Floating Hemispherical Helical Antenna: Analysis of Gain, Efficiency and Resonant Frequency
This paper reports the effect of seawater conductivity on gain, efficiency and resonant frequency of a hemispherical helical antenna. The size of the copper ground plane for the hemispherical antenna can be reduced using conductive seawater as part of the ground plane for the antenna. Seawater increases the gain from 6 dBi to 8 dBi but with a decreased efficiency. The simulated radiation efficiency of the antenna on water surface is 61%. Specific Absorption Rate (SAR) results show absorption of 2.19 W/kg. This paper also reports the design of a low cost floating buoy. The buoy provides a waterproof setup for the circuitry and antenna. The buoy can be effectively used for shallow water coastal monitoring
High statistics study of the reaction
The photoproduction of 2 mesons off protons was studied with the
Crystal Barrel/TAPS experiment at the electron accelerator ELSA in Bonn. The
energy of photons produced in a radiator was tagged in the energy range from
600\,MeV to 2.5\,GeV. Differential and total cross sections and
Dalitz plots are presented. Part of the data was taken with a diamond radiator
producing linearly polarized photons, and beam asymmetries were derived.
Properties of nucleon and resonances contributing to the
final state were determined within the BnGa partial wave analysis. The data
presented here allow us to determine branching ratios of nucleon and
resonances for their decays into via several intermediate states.
Most prominent are decays proceeding via , ,
, , but also , , and
contribute to the reaction.Comment: 28 pages, 17 figures, 7 table
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