Pulsatile shear and Gja5 modulate arterial identity and remodeling events during flow-driven arteriogenesis

In the developing chicken embryo yolk sac vasculature, the expression of arterial identity genes requires arterial hemodynamic conditions. We hypothesize that arterial flow must provide a unique signal that is relevant for supporting arterial identity gene expression and is absent in veins. We analyzed factors related to flow, pressure and oxygenation in the chicken embryo vitelline vasculature in vivo. The best discrimination between arteries and veins was obtained by calculating the maximal pulsatile increase in shear rate relative to the time-averaged shear rate in the same vessel: the relative pulse slope index (RPSI). RPSI was significantly higher in arteries than veins. Arterial endothelial cells exposed to pulsatile shear in vitro augmented arterial marker expression as compared with exposure to constant shear. The expression of Gja5 correlated with arterial flow patterns: the redistribution of arterial flow provoked by vitelline artery ligation resulted in flow-driven collateral arterial network formation and was associated with increased expression of Gja5. In situ hybridization in normal and ligation embryos confirmed that Gja5 expression is confined to arteries and regulated by flow. In mice, Gja5 (connexin 40) was also expressed in arteries. In the adult, increased flow drives arteriogenesis and the formation of collateral arterial networks in peripheral occlusive diseases. Genetic ablation of Gja5 function in mice resulted in reduced arteriogenesis in two occlusion models. We conclude that pulsatile shear patterns may be central for supporting arterial identity, and that arterial Gja5 expression plays a functional role in flow-driven arteriogenesis.

Internationaler Zivilprozess 2011, Zusammenspiel des revLugÜ mit dem revSchKG und der schweizerischen ZPO, mit Beiträgen von Prof. Dr. Jürgen Brönnimann, Prof. Dr. Felix Dasser, Prof. Dr. Alexander R. Markus, Prof. Dr. Rodrigo Rodriguez, Prof. Dr. Daniel Staehelin, Prof. Dr. Walter A. Stoffel

Am 10. September 2010 fand in Bern die erste Schweizerische Tagung für Zivilverfahrensrecht des Instituts für Internationales Privatrecht und Verfahrensrecht der Universität Bern statt. Die Tagung mit dem Titel "Internationaler Zivilprozess 2011" befasste sich mit dem Zusammenspiel der am 1.1.2011 in Kraft tretenden neuen oder revidierten Erlasse (ZPO, revLugÜ, und revSchKG) im Rahmen des internationalen Zivilprozesses. Der Tagungsband enthält auf den Tagungsvorträgen basierende Beiträge namhafter Autoren zu aktuellen und praxisrelevanten Themen des neuen internationalen Zivilprozesses, namentlich zum neuen Arrestrecht, zur Behandlung von Zustellungsmängeln unter dem revLugÜ, zum Zahlungsbefehl im Lichte der revLugÜ-Zuständigkeiten, zur vollstreckbaren öffentliche Urkunde sowie zur Rechtshängigkeit und zur Streitgenossenschaft im internationalen Verhältnis. Der Tagungsband "Internationaler Zivilprozess 2011" eröffnet eine neue Schriftenreihe zum Internationalen Privatrecht und Verfahrensrecht.

The Trypanosoma brucei MitoCarta and its regulation and splicing pattern during development

It has long been known that trypanosomes regulate mitochondrial biogenesis during the life cycle of the parasite; however, the mitochondrial protein inventory (MitoCarta) and its regulation remain unknown. We present a novel computational method for genome-wide prediction of mitochondrial proteins using a support vector machine-based classifier with approximately 90% prediction accuracy. Using this method, we predicted the mitochondrial localization of 468 proteins with high confidence and have experimentally verified the localization of a subset of these proteins. We then applied a recently developed parallel sequencing technology to determine the expression profiles and the splicing patterns of a total of 1065 predicted MitoCarta transcripts during the development of the parasite, and showed that 435 of the transcripts significantly changed their expressions while 630 remain unchanged in any of the three life stages analyzed. Furthermore, we identified 298 alternatively splicing events, a small subset of which could lead to dual localization of the corresponding proteins.

Vorsorglicher Rechtsschutz. Vorsorgliche Massnahmen im internationalen Kontext, offene Fragen im neuen Arrestrecht und Sicherungsmassnahmen der ZPO, mit Beiträgen von Dr. Isabelle Chabloz, Dr. Richard Gassmann, PD Dr. Pascal Grolimund, Dr. Jürg Roth, Prof. Dr. Daniel Staehelin

Am 9. September 2011 führte das Institut für Verfahrensrecht und Internationales Privatrecht (CIVPRO) der Universität Bern in bewährter Zusammenarbeit mit der schweizerischen SchKG-Vereinigung die zweite Schweizer Tagung für Internationales Zivilverfahrensrecht durch. Im Mittelpunkt der Tagung standen vorsorgliche Massnahmen im internationalen Kontext vor dem Hintergrund der neuesten Entwicklungen, namentlich (aber nicht nur) des neuen Lugano-Übereinkommens. Der Tagungsband enthält die auf den Vorträgen basierenden, überarbeiteten und erweiterten Beiträge namhafter Autorinnen und Autoren zum vorsorglichen Rechtsschutz im neuen IZPR (Pascal Grolimund). Besondere Aufmerksamkeit gilt dem neuen Arrestrecht sowohl im als auch ausserhalb des Anwendungsbereichs des Lugano-Übereinkommens (Richard Gassmann und Jürg Roth). Ebenso enthält der Band Beiträge zu den Sicherungsmassnahmen in der Realvollstreckung (Daniel Staehelin) sowie zur Anerkennung ausländischer vorsorglicher Massnahmen (Isabelle Chabloz).

An integral conservative gridding--algorithm using Hermitian curve interpolation

The problem of re-sampling spatially distributed data organized into regular or irregular grids to finer or coarser resolution is a common task in data processing. This procedure is known as 'gridding' or 're-binning'. Depending on the quantity the data represents, the gridding-algorithm has to meet different requirements. For example, histogrammed physical quantities such as mass or energy have to be re-binned in order to conserve the overall integral. Moreover, if the quantity is positive definite, negative sampling values should be avoided. The gridding process requires a re-distribution of the original data set to a user-requested grid according to a distribution function. The distribution function can be determined on the basis of the given data by interpolation methods. In general, accurate interpolation with respect to multiple boundary conditions of heavily fluctuating data requires polynomial interpolation functions of second or even higher order. However, this may result in unrealistic deviations (overshoots or undershoots) of the interpolation function from the data. Accordingly, the re-sampled data may overestimate or underestimate the given data by a significant amount. The gridding-algorithm presented in this work was developed in order to overcome these problems. Instead of a straightforward interpolation of the given data using high-order polynomials, a parametrized Hermitian interpolation curve was used to approximate the integrated data set. A single parameter is determined by which the user can control the behavior of the interpolation function, i.e. the amount of overshoot and undershoot. Furthermore, it is shown how the algorithm can be extended to multidimensional grids. The algorithm was compared to commonly used gridding-algorithms using linear and cubic interpolation functions. It is shown that such interpolation functions may overestimate or underestimate the source data by about 10-20%, while the new algorithm can be tuned to significantly reduce these interpolation errors. The accuracy of the new algorithm was tested on a series of x-ray CT-images (head and neck, lung, pelvis). The new algorithm significantly improves the accuracy of the sampled images in terms of the mean square error and a quality index introduced by Wang and Bovik (2002 IEEE Signal Process. Lett. 9 81-4).

Guidelines for the use and interpretation of assays for monitoring autophagy in higher eukaryotes

Research in autophagy continues to accelerate,(1) and as a result many new scientists are entering the field. Accordingly, it is important to establish a standard set of criteria for monitoring macroautophagy in different organisms. Recent reviews have described the range of assays that have been used for this purpose.(2,3) There are many useful and convenient methods that can be used to monitor macroautophagy in yeast, but relatively few in other model systems, and there is much confusion regarding acceptable methods to measure macroautophagy in higher eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers of autophagosomes versus those that measure flux through the autophagy pathway; thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from fully functional autophagy that includes delivery to, and degradation within, lysosomes (in most higher eukaryotes) or the vacuole (in plants and fungi). Here, we present a set of guidelines for the selection and interpretation of the methods that can be used by investigators who are attempting to examine macroautophagy and related processes, as well as by reviewers who need to provide realistic and reasonable critiques of papers that investigate these processes. This set of guidelines is not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to verify an autophagic response.