The value of different resistance parameters in distinguishing biopsy-proved dysfunction of renal allografts

The data concerning the value of duplex sonography in diagnosing parenchymatous renal allograft dysfunction are controversial. Most early studies did not take into consideration the many factors influencing resistance parameters. We therefore performed a prospective, biopsy-controlled study with exclusion of all known sources of error regarding resistance parameters. Furthermore we investigated the value of a new resistance parameter, the systolic deceleration percentage. Forty-seven duplex sonographic studies were performed on 43 patients (30 male, 13 female, median age 47 years, range 7-70). Fourteen studies were done on normally functioning grafts (control group) an average of 33 days after transplantation. Thirty-three studies were performed on dysfunctional grafts immediately prior to biopsy. Grafts which had been transplanted more than a year previously or with vascular findings or any other clinical or sonographic pathology probably explaining function deterioration were excluded. In all patients, the resistive index (RI), pulsatility index (PI) and systolic deceleration percentage (DP) were calculated in the main renal artery and in the interlobar artery. Of the 33 grafts with dysfunction, nine had vascular rejection (VR), 11 interstitial rejection (IR), 11 cyclosporin A toxicity (CAT) and two other histologies (OR). The mean RI in normal grafts (NO) was 0.71±0.06 in the main artery and 0.68±0.06 in the interlobar artery, in VR 0.86±0.12 and 0.80±0.18, in IR 0.72±0.05 and 0.70±0.07, in CAT 0.67±0.06 and 0.65±0.07 and in OR 0.64±0.07 and 0.60±0.01. For PI, the values were 1.45±0.23 and 1.41±0.28 (NO), 3.5±2.13 and 2.92±2.16 (VR), 1.55±0.26 and 1.46±0.33 (IR), 1.32±0.25 and 1.27±0.26 (CAT) and 1.30±0.34 and 1.13±0.04 (OR). For DP we calculated 28±5% and 29±6% (NO), 43±14% and 36±6% (VR), 29±9% and 27±9% (IR), 31±8% and 32±7% (CAT ) and 32±4% and 28±3% (OR). The sensitivity/specificity for VR with a cutoff mean+2 SD was 0.44/1 for RI, 0.55/0.97 for PI and 0.33/0.89 for DP. It was concluded that:(1) despite the high selection of our patient group, diagnostic accuracy of duplex sonography for diagnosing parenchymatous function disorder in renal allograft remains insufficient; (2) in vascular rejection only, the resistance parameters differ significantly from the values of normal allografts; (3) the higher the cutoff of resistance parameters, the better the specificity and the worse the sensitivity for diagnosing vascular rejection; (4) of all investigated resistance parameters, the RI is the most practical due to a simple measurement techniqu

Mindestkurs für den Schweizer Franken: Gefährlicher Interventionismus der SNB?

Die Schweiz ist in den vergangenen Monaten durch die drastische Aufwertung des Schweizer Franken gegenüber dem Euro unter Druck geraten. Im September 2011 verkündete deshalb die Schweizerische Nationalbank (SNB) einen Mindestkurs des Franken zum Euro. Mit einer Untergrenze von 1,20 Franken je Euro soll der nach Ansicht der SNB »massiven Überbewertung« der Währung entgegengewirkt werden. Oliver Landmann, Universität Freiburg, sieht diese Maßnahme vor dem Hintergrund, dass die Schweiz als kleine offene Volkswirtschaft auch als Nicht-Mitglied der Europäischen Union aufs Engste mit ihrem politischen und wirtschaftlichen Umland verbunden ist. Das bedeutet, dass das Land von allen positiven wie negativen Entwicklungen in der EU betroffen sein wird. Deshalb wäre es eine Illusion zu glauben, die Schwierigkeiten, in welche die Eurozone durch ihre aktuelle Krise geraten ist, könnten an der Schweiz vorbeigehen. Die Festlegung eines Mindestkurses von 1,20 Fr. ist zwar kein Wundermittel, aber eine »mit Bedacht ergriffene Maßnahme der Schadensminimierung«. Gunther Schnabl, Universität Leipzig, betont, dass die Schweiz mit dieser Entscheidung geldpolitischen Handlungsspielraum zurückgewinnt, da sie sich »von dem Fluch spekulativer Kapitalzuflüsse« teilweise befreien kann. Allerdings bleibe die Wechselkursbindung im derzeitigen Umfeld der globalen Liquiditätsschwemme sowie instabiler europäischer Staatshaushalte und Banken nur eine unbefriedigende Lösung. Denn bei festem Wechselkurs und steigender Inflation werden die immensen Euro-Reserven in der Schweizerischen Zentralbankbilanz langfristig real entwertet. Damit werde die Sozialisierung der Kosten der europäischen Staatsschulden- und Finanzkrisen auf die Schweiz ausgeweitet. David Iselin und Michael J. Lamla, KOF Konjunkturforschungsstelle der ETH Zürich, werten die Einführung der Wechselkursuntergrenze als Erfolg und das Risiko dieses Engagements der SNB als gering. Angesichts der erwarteten niedrigen Inflationsraten im nächstenSchweizer Franken, Wechselkurs, Wechselkurspolitik, Finanzmarktkrise, Eurozone, Interventionismus, Zentralbank, Schweiz

Early renal transplant dysfunction due to arterial kinking stenosis

The main differential diagnoses of early renal trans-plant dysfunction include ischaemic damage, cyclospo-rin toxicity, and rejection [1]. Rarer causes include bleeding, ureteral obstruction, urinary leak, venou

CD14 Works with Toll-Like Receptor 2 to Contribute to Recognition and Control of Listeria monocytogenes Infection

Toll-like receptor 2 (TLR2) signaling has been shown to contribute to resistance to Listeria monocytogenes infection, as TLR2-deficient mice have a heightened susceptibility to infection with this organism. Because CD14 may associate with TLR2, we investigated the role of CD14 in Listeria responses. In both CD14-deficient and TLR2- deficient macrophages, nuclear factor κB translocation; CD40 and CD86; and the production of interleukin (IL)- 12, IL-6, tumor necrosis factor, and nitric oxide are reduced. The absence of CD14 augmented susceptibility to Listeria infection, reduced survival, and diminished bacterial clearance, as observed in TLR2-deficient mice.Compared with C57BL/6 control mice, CD14-deficient mice were observed to have a greater number of hepatic microabscesses containing abundant neutrophils, these abscesses were larger in size, and there was reduced inducible nitric oxide synthase expression. Further, mice that are both CD14 deficient and TLR2 deficient display susceptibility to infection that is comparable to that of mice deficient in either CD14 or TLR2 alone. Therefore, the present data demonstrate the role of CD14 and TLR2 in the recognition and control of Listeria infection and host resistanc

The Open Global Glacier Model (OGGM) v1.1

Despite their importance for sea-level rise, seasonal water availability, and as a source of geohazards, mountain glaciers are one of the few remaining subsystems of the global climate system for which no globally applicable, open source, community-driven model exists. Here we present the Open Global Glacier Model (OGGM), developed to provide a modular and open-source numerical model framework for simulating past and future change of any glacier in the world. The modeling chain comprises data downloading tools (glacier outlines, topography, climate, validation data), a preprocessing module, a mass-balance model, a distributed ice thickness estimation model, and an ice-flow model. The monthly mass balance is obtained from gridded climate data and a temperature index melt model. To our knowledge, OGGM is the first global model to explicitly simulate glacier dynamics: the model relies on the shallow-ice approximation to compute the depth-integrated flux of ice along multiple connected flow lines. In this paper, we describe and illustrate each processing step by applying the model to a selection of glaciers before running global simulations under idealized climate forcings. Even without an in-depth calibration, the model shows very realistic behavior. We are able to reproduce earlier estimates of global glacier volume by varying the ice dynamical parameters within a range of plausible values. At the same time, the increased complexity of OGGM compared to other prevalent global glacier models comes at a reasonable computational cost: several dozen glaciers can be simulated on a personal computer, whereas global simulations realized in a supercomputing environment take up to a few hours per century. Thanks to the modular framework, modules of various complexity can be added to the code base, which allows for new kinds of model intercomparison studies in a controlled environment. Future developments will add new physical processes to the model as well as automated calibration tools. Extensions or alternative parameterizations can be easily added by the community thanks to comprehensive documentation. OGGM spans a wide range of applications, from ice–climate interaction studies at millennial timescales to estimates of the contribution of glaciers to past and future sea-level change. It has the potential to become a self-sustained community-driven model for global and regional glacier evolution.</p