Covered stents versus Bare-metal stents in chronic atherosclerotic Gastrointestinal Ischemia (CoBaGI): Study protocol for a randomized controlled trial

Background: Chronic mesenteric ischemia (CMI) is the result of insufficient blood supply to the gastrointestinal tract and is caused by atherosclerotic stenosis of one or more mesenteric arteries in > 90% of cases. Revascularization therapy is indicated in patients with a diagnosis of atherosclerotic CMI to relieve symptoms and to prevent acute-on-chronic mesenteric ischemia, which is associated with high morbidity and mortality. Endovascular therapy has rapidly evolved and has replaced surgery as the first choice of treatment in CMI. Bare-metal stents (BMS) are standard care currently, although retrospective studies suggested significantly highe

Effects of aluminium and pH on growth and potassium uptake by three ectomycorrhizal fungi in liquid culture

Soil acidification and Al toxicity may be important factors in the decline in vitality of many forest trees and the associated ectomycorrhizal fungal flora. In this study, effects of low pH and high Al concentrations were investigated on both growth and K+ uptake by three Douglas-fir ectomycorrhizal fungi in solution culture. In growth experiments, Lactarius rufus and Lactarius hepaticus appeared to be tolerant to low pH but sensitive to Al. In contrast, laccaria bicolor exhibited high Al tolerance and high sensitivity to acidification. Al toxicity in both Lactarius isolates was alleviated by an increase in the orthophosphate concentration from 20 to 120 μM, whereas it was not influenced by an increase in Ca concentration. Elevation of the Mg concentration alleviated Al toxicity in Lactarius rufus, but not in Lactarius hepaticus, although growth was stimulated in this fungus. Net K+ uptake by a 2-week-old (log phase) mycelium was determined as function of both Al and medium pH, at a K+ concentration of 100 μM. The fungal species each exhibited specific pH optima for K+} uptake. At pHs below 4, K+ uptake rate was decreased in each species. High Al concentrations severely inhibited K+ uptake in Lactarius hepaticus, but not in the other species

Overflow Behavior in Queues with Many Long-Tailed Inputs

We consider a fluid queue fed by a superposition of n homogeneous on-off sources with generally distributed on- and off-periods. We scale buffer space B and link rate C by n, such that we get nb and nc, respectively. Then we let n grow large. In this regime, the overflow probability decays exponentially in the number of sources n; we specifically examine the situation in which also b is large. We explicitly compute asymptotics for the case in which the on-periods have a subexponential distribution, e.g., Pareto, Lognormal, or Weibull. We provide a detailed interpretation of our results. Crucial is the shape of the function v(t) := -log P(A* > t) for large t, A* being the residual on-period. If v(·) is slowly varying (e.g., Pareto, Lognormal), then, during the trajectory to overflow, the input rate will only slightly exceed the link rate. Consequently, the buffer will fill `slowly', and the typical time to overflow will be `more than linear' in the buffer size. In contrast, if v(·) ..

Kinetics of NH4+ and K+ uptake by ectomycorrhizal fungi. Effect of NH4+ on K+ uptake

NH4+ and K+ uptake experiments have been conducted with 3 ectomycorrhizal fungi, originating from Douglas fir (Pseudotsuga menziesii (Mirb.] Franco) stands. At concentrations up to 250 μM, uptake of both NH4+ and K+ follow Michaelis‐Menten kinetics. Laccaria bicolor (Maire) P. D. Orton, Lactarius rufus (Scop.) Fr. and Lactarius hepaticus Plowr. ap. Boud. exhibit Km values for NH4+ uptake of 6, 35, and 55 μM, respectively, and Km values for K+ uptake of 24, 18, and 96 μM, respectively. Addition of 100 μM NH4+ raises the Km of K+ uptake by L. bicolor to 35 μM, while the Vmax remains unchanged. It is argued that the increase of Km is possibly caused by depolarization of the plasma membrane. It is not due to a competitive inhibition of K+ by NH4+ since the apparent inhibitor constant is much higher than the Km, for NH4+ uptake. The possibility that NH4+ and K+ are taken up by the same carrier can be excluded. The Km, values for K+ uptake in the two other fungi are not significantly affected by 100 μM NH4+. Except for a direct effect of NH4+ on influx of K+ into the cells, there may also be an indirect effect after prolonged incubation of the cells in the presence of 100 μM NH4+

The effect of aluminium on phosphate uptake by three isolated ectomycorrhizal fungi

Three ectomycorrhizal fungi, Laccaria bicolor, Lactarius hepaticus and Lactarius rufus, were grown in liquid medium for 2 weeks and used in short-term phosphate (P) uptake studies. At phosphate concentrations ranging from 1 to 100 μM the fungi exhibited a single affinity phase. The kinetic parameters for P uptake differed between species with Km varying from 1.5 to 13.1 μM. Vmax also depended on the buffer that was applied. P uptake by the fungi was severely reduced by aluminium (Al). This could be ascribed mainly to the complexing of phosphate by Al3+. Correcting for this decrease in phosphate concentration, the uptake by both Lactarius hepaticus and Laccaria bicolor was only slightly inhibited by Al, while P uptake by Lactarius rufus was even stimulated. The latter may be attributed to a reduction in surface potential caused by the trivalent Al cation, which in turn increases the concentration of the negatively charged phosphate ion in the near-membrane region

The Dutch Audit of Carotid Interventions: Transparency in Quality of Carotid Endarterectomy in Symptomatic Patients in the Netherlands

Background The Dutch Audit for Carotid Interventions (DACI) registers all patients undergoing interventions for carotid artery stenosis in the Netherlands. This study describes the design of the DACI and results of patients with a symptomatic stenosis undergoing carotid endarterectomy (CEA). It aimed to evaluate variation between hospitals in process of care and (adjusted) outcomes, as well as predictors of major stroke/death after CEA. Methods All patients with a symptomatic stenosis, who underwent CEA and were registered in the DACI between 2014 and 2016 were included in this cohort. Descriptive analyses of patient characteristics, process of care, and outcomes were performed. Casemix adjusted hospital procedural outcomes as (30 day/in hospital) mortality, stroke/death, and major stroke/death, were compared with the national mean. A multivariable logistic regression model (backward elimination at p > 0.10) was used to identify predictors of major stroke/death. Results A total of 6459 patients, registered by 52 hospitals, were included. The majority (4,832, 75%) were treated <2 weeks after their first hospital consultation, varying from 40% to 93% between hospitals. Mortality, stroke/death, and major stroke/death were, respectively, 1.1%, 3.6%, and 1.8%. Adjusted major stroke/death rates for hospital comparison varied between 0 and 6.5%. Nine hospitals performed significantly better, none performed significantly worse. Predictors of major stroke/death were sex, age, pulmonary disease, presenting neurological symptoms, and peri-operative shunt. Conclusion CEA in The Netherlands is associated with an overall low mortality and (major) stroke/death rate. Whereas the indicator time to intervention varied between hospitals, mortality and (major) stroke/death were not significantly distinctive enough to identify worse practices and therefore were unsuitable for hospital comparison in the Dutch setting. Additionally, predictors of major stroke/death at population level could be identified

Strained, Stable 2-Aza-1-Phosphabicyclo[n.1.0]alkane and -alkene Fe(CO)4 Complexes with Dynamic Phosphinidene Behavior

The synthesis of highly strained bicyclic phosphirane and phosphirene iron-tetracarbonyl complexes, that is, complexes with 2-aza-l-phosphabicyclo[n. 1.0]alkanes and -alkenes (n = 3-5), is explored by using intramolecular cycloaddition of an in situ generated electrophilic phosphinidene complex, [R(iPr)NP=Fe(CO

Bioavailability of rifampicin in Indonesian subjects: a comparison of different local drug manufacturers.

Contains fulltext : 57699.pdf (publisher's version ) (Closed access)To examine the bioavailability of rifampicin formulations produced in Indonesia, we conducted a single-dose, double-blind, cross-over bioavailability study. Antituberculosis drugs from three Indonesian manufacturers and one international manufacturer were compared in 12 healthy Indonesian subjects. Out of three local manufacturers, two showed equal bioavailability compared to the reference standard, and one showed slightly lower bioavailability (ratio 0.86; 90% confidence interval 0.80-0.91) and substandard rifampicin content of drug preparations. Plasma rifampicin concentrations in this study were more than three-fold higher than concentrations recently found in tuberculosis patients in Indonesia, which suggests that unknown (disease-related) determinants may reduce the bioavailability of rifampicin formulations