OFELIA is an experimental network designed to offer a diverse OpenFlow-enabled infrastructure to allow Software Defined Networking (SDN) experimentation. OFELIA is currently composed of ten ...sub-testbeds (called islands), most of them in Europe and one in Brazil. An experimenter get access to a so-called slice; a subset of the testbed resources like nodes and links, including the Openflow programmable switches to carry on an experiment. A new network virtualization tool called VeRTIGO has been recently presented to extend the way isolation is achieved between slices (slicing), allowing each experimenter to instantiate an arbitrary virtual network topology on top of a physical testbed. In this paper we present preliminary results obtained by deploying and using VeRTIGO in an experiment running across several OFELIA islands, which has proven to increase flexibility to experimenters willing to play with novel SDN concepts at large scale.
We analyse all available X-ray observations of X1822-371 made with XMM-Newton, Chandra, Suzaku and INTEGRAL satellites. The observations were not simultaneous. The Suzaku and INTEGRAL broad band ...energy coverage allows us to constrain the spectral shape of the continuum emission well. We use the model already proposed for this source, consisting of a Comptonised component absorbed by interstellar matter and partially absorbed by local neutral matter, and we added a Gaussian feature in absorption at \(\sim 0.7\) keV. This addition significantly improves the fit and flattens the residuals between 0.6 and 0.8 keV. We interpret the Gaussian feature in absorption as a cyclotron resonant scattering feature (CRSF) produced close to the neutron star surface and derive the magnetic field strength at the surface of the neutron star, \((8.8 \pm 0.3) \times 10^{10}\) G for a radius of 10 km. We derive the pulse period in the EPIC-pn data to be 0.5928850(6) s and estimate that the spin period derivative of X1822-371 is \((-2.55 \pm 0.03) \times 10^{-12}\) s/s using all available pulse period measurements. Assuming that the intrinsic luminosity of X1822-371is at the Eddington limit and using the values of spin period and spin period derivative of the source, we constrain the neutron star and companion star masses. We find the neutron star and the companion star masses to be \(1.69 \pm 0.13\) M\(_{\odot}\) and \(0.46 \pm 0.02\) M\(_{\odot}\), respectively, for a neutron star radius of 10 km.In a self-consistent scenario in which X1822-371 is spinning-up and accretes at the Eddington limit, we estimate that the magnetic field of the neutron star is \((8.8 \pm 0.3) \times 10^{10}\) G for a neutron star radius of 10 km. If our interpretation is correct, the Gaussian absorption feature near 0.7 keV is the very first detection of a CRSF below 1 keV in a LMXB. (abridged)
The finding of high plasma free fatty acid (FFA) levels in cirrhotic patients has been attributed either to decreased hepatic clearance or to enhanced fat mobilization. To better clarify these ...hypotheses, total and individual FFA and glycerol levels were determined in 21 cirrhotic patients with different degrees of hepatocellular damage (evaluated by liver function tests), portal hypertension (evaluated by endoscopy and clinical signs), and nutritional status (evaluated by anthropometric and biohumoral parameters) and in 10 age- and sex-matched healthy subjects. Glucose tolerance and insulin and glucagon levels were determined in all individuals. Well-nourished and malnourished patients were identified within the cirrhotic group. Plasma FFA and glycerol concentrations were well correlated (r = 0.47, P less than 0.05), levels being significantly higher in cirrhotic individuals than in controls (746.6 +/- 46.29 SE v 359.22 +/- 40.82 mumol/L, P less than 0.001 for plasma FFA; 150.1 +/- 3.12 v 82.5 +/- 9.2 mumol/L, P less than 0.01 for glycerol). Plasma FFA and glycerol showed no correlation with the liver function test results or portal hypertension parameters. Interestingly, plasma levels of FFA and glycerol were influenced by the nutritional status, significantly higher FFA levels being observed in the well-nourished than in the malnourished patients (842.5 +/- 47.5 v 563.4 +/- 78 mumol/L, P less than 0.005). Furthermore, a positive correlation was found between plasma glycerol level and percentage of triceps skinfold (r = 0.45, P less than 0.05). No correlation was found between plasma levels of FFA or glycerol and glucose tolerance, insulin and glucagon.
This is a study of the incidence and clinicopathological significance of focal segmental glomerulosclerosis (FSG) in 154 renal allografts (22 biopsies, 128 nephrectomies and four necropsies) from 137 ...cadaveric and 17 living-related donors. FSG was identified in 18 grafts (11.7%) from 16 patients: six as recurrent FSG in four patients (two developed FSG in two consecutive transplants) and 12 as de novo FSG. The incidence of recurrent FSG in patients who had FSG as their original kidney disease was 30.8% whereas that of de novo FSG in patients who had renal diseases other than FSG was 8.7%. Histologically, recurrent FSG was characterized by mild degrees of obliterative arteriopathy of rejection and preferential involvement of the juxtamedullary glomeruli. Whereas, in de novo FSG, the occlusive vascular changes of rejection were severe and the glomeruli in the outer cortical region were mostly involved. Clinically, however, the differences between them were less clear, although nephrotic syndrome tends to occur more often and earlier in patients with recurrent FSG. Obliterative arteriopathy of chronic rejection and consequent glomerular ischemia appeared to be of major importance in the pathogenesis of de novo FSG in renal allografts.
Recurrent episodes of hepatic encephalopathy (HE) frequently occur in surgically shunted cirrhotic patients. The prevention of these episodes is based mainly on the long-term use of lactulose. ...Recently, lactitol, a nonabsorbable disaccharide similar to lactulose, has been proposed as an alternative in the management of HE. It has the advantage of being better tolerated and producing a more predictable catharsis. The effects of the two agents were compared in a controlled randomized study lasting six months involving 31 cirrhotic patients with portal-systemic shunt, of whom 40% experienced HE. The PSE index (mental state, EEG, asterixis, Raitan test, and ammonia) was assessed in each patient on entry to the study and every three months during treatment. Episodes of HE, side effects, and the patients' comments on efficacy, tolerability, and palatability were recorded. The dose required to induce two bowel movements per day was 48 +/- 25 ml of lactulose syrup and 36 +/- 7 g of lactitol. During the study, the number of patients who had an episode of HE and the PSE index was similar in both groups. The patients judged lactitol better from the point of view of palatability. Meteorism and flatulence, experienced by patients treated with lactulose, was not reported by the lactitol group. We concluded that lactitol is as effective as lactulose in the long-term prevention of episodes of HE in cirrhotics with portal-systemic shunt and may be better tolerated.
Transjugular intrahepatic portosystemic shunt (TIPS), a new technique for the treatment of portal hypertension, has been successful in preliminary studies to treat acute variceal hemorrhage and to ...prevent variceal rebleeding. The purpose of this multicenter, randomized controlled trial is to compare the efficacy of TIPS with that of endoscopic sclerotherapy in the prevention of variceal rebleeding in cirrhosis. Eighty-one cirrhotic patients, with endoscopically proven variceal bleeding, were randomized to either TIPS (38 patients) or endoscopic sclerotherapy (43 patients). Randomization was stratified according to the following: if bleeding occurred < 1 week (stratum I); if bleeding occurred 1 to 6 weeks (stratum II); and if bleeding occurred 6 weeks to 6 months (stratum III) before enrollment. Follow-up included clinical, biochemical, Doppler Ultrasound, and endoscopic examinations every 6 months. During a mean follow-up of 17.7 months, 51% of the patients treated with sclerotherapy and 24% of those treated with TIPS rebled (P = .011). Mortality was 19% in sclerotherapy patients and 24% in TIPS patients (P = .50). Hepatic encephalopathy (HE) developed in 26% and 55%, respectively (P = .006). A separate analysis of the three strata showed that TIPS was significantly more effective than sclerotherapy (P = .026) in preventing rebleeding only in stratum I patients. TIPS is significantly better than sclerotherapy in preventing rebleeding only when it is performed shortly after a variceal bleed; however, TIPS does not improve survival and is associated with a significantly higher incidence of HE. The overall performance of TIPS does not seem to justify the adoption of this technique as a first-choice treatment to prevent rebleeding from esophageal varices in cirrhotic patients.
We developed a new and simplified donor-specific blood transfusion (DSBT) protocol for prospective kidney transplant recipients from one-haplotype-mismatched related donors. Prospective kidney donors ...gave 450 ml of blood in a quad-pack unit, and the blood was stored in a blood bank. Twenty-five patients were transfused with 100 ml of the respective donor's whole blood at 1, 8, and 15 days after its storage. After DSBT, only three (12%) developed donor-specific lymphocytotoxic antibodies. Following DSBT, donor-specific mixed lymphocyte culture (MLC) was significantly suppressed, without any accelerated (secondary-type) response in early MLC. In addition, sera obtained after DSBT also suppressed donor-specific MLC significantly. Sixteen recipients subsequently received a kidney transplant from the donor, and all had functioning grafts at three months, but one lost the graft thereafter (graft survival rate: 94% at 12 months). This study indicates that (1) 100 ml of stored whole-blood DSBT three times at weekly intervals is a practical, less immunizing, and effective approach to enhance graft survival in recipients of a one-haplotype-mismatched graft; and (2) immune consequences of DSBT include induction of donor-specific cellular and humoral adaptive responses that might be conducive to successful graft outcome.
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