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Steinau an der Straße, Germany

Ito H.,Kyushu Institute of Technology | Dashkovskiy S.,FH Erfurt | Wirth F.,University of Wrzburg
Automatica | Year: 2012

This paper addresses the problem of verifying stability of networks whose subsystems admit dissipation inequalities of integral input-to-state stability (iISS). We focus on two ways of constructing a Lyapunov function satisfying a dissipation inequality of a given network. Their difference from one another is elucidated from the viewpoint of formulation, relation, fundamental limitation and capability. One is referred to as the max-type construction resulting in a Lipschitz continuous Lyapunov function. The other is the sum-type construction resulting in a continuously differentiable Lyapunov function. This paper presents geometrical conditions under which the Lyapunov construction is possible for a network comprising n<2 subsystems. Although the sum-type construction for general n>2 has not yet been reduced to a readily computable condition, we obtain a simple condition of iISS small gain in the case of n=2. It is demonstrated that the max-type construction fails to offer a Lyapunov function if the network contains subsystems which are not input-to-state stable (ISS). © 2012 Elsevier Ltd. All rights reserved.

A new species of Plagiotriptus is described from the Taita Hills of Kenya, East Africa. Data on habitat and co-occurring Saltatoria species are given and an updated key provided to the species of Plagiotriptus. .

Segerer S.E.,University of Wurzburg | Rieger L.,University of Wurzburg | Kapp M.,University of Wurzburg | Dombrowski Y.,Ludwig Maximilians University of Munich | And 3 more authors.
Human Reproduction | Year: 2012

BACKGROUND: Macrophage inhibitory cytokine-1 (MIC-1) is a multifunctional cytokine produced in high amounts by placental tissue. Inhibiting trophoblast invasion and suppressing inflammation through inhibition of macrophage activation, MIC-1 is thought to provide pleiotropic functions in the establishment and maintenance of pregnancy. So far, little is known about the decidual cell subsets producing MIC-1 and the effect of this cytokine on dendritic cells (DCs), which are known to play a distinct role in the development of pro-fetal tolerance in pregnancy. METHODS: To identify the decidual cell types expressing and secreting MIC-1, immunohistochemical staining, PCR experiments, western blot analysis and ELISAs were performed. Immature DCs (iDCs) were generated from peripheral blood-derived monocytes and differentiated in the presence of MIC-1 or dexamethasone (Dex) for control. Migratory and proliferative activity of DCs after MIC-1 exposure was investigated by migration and proliferation assay. Cytokine secretion after MIC-1 exposure was tested in isolated uNK cells, isolated CD14 monocytes, monocyte-derived iDCs and mature DCs. Subsequently, the phenotype of DCs was studied using FACS analysis. To test the T-cell stimulatory capacity of pre-incubated DCs, mixed lymphocyte reaction was applied. Finally, the expression of the tryptophan-catabolizing enzyme indoleamine 2,3-dioxygenase (IDO) after the exposure of MIC-1 to maturing DCs was analysed by western blot. RESULTS: Immunohistochemical staining, PCR and western blot experiments demonstrated that MIC-1 is mainly expressed by trophoblast cells and decidual stromal cells. Analysis of the MIC-1 secretion of decidual cell types by ELISA again characterized trophoblast and stromal cells as main producers. The migratory activity of iDCs was significantly induced by MIC-1. No changes in proliferative activity of DCs were observed after MIC-1 pre-incubation. The secretion of pro- or anti-inflammatory cytokines was not affected significantly by MIC-1. Studying the phenotype of DCs after MIC-1 exposure by FACS analysis, we observed that MIC-1 suppresses the expression of typical maturation molecules such as CD25 and CD83 as well as of CD86 during cytokine-induced DC maturation similar to Dex. In addition, T-cell stimulatory capacity of DCs was significantly reduced after MIC-1 exposure. MIC-1 was also able to increase slightly the expression of IDO (a key immunomodulatory enzyme promoting periphereal tolerance) in maturing DCs. CONCLUSIONS: We have identified MIC-1 as a novel factor (secreted by decidual cells in early pregnancy) that could promote the increase of a tolerogenic subtype of DC in decidua. © The Author 2011.

Gascoyne R.D.,British Columbia Cancer Agency | Rosenwald A.,University of Wrzburg | Poppema S.,University of Groningen | Lenz G.,Charite - Medical University of Berlin
Leukemia and Lymphoma | Year: 2010

There has recently been a rapid expansion in research aimed at identifying biomarkers that could improve the prognosis for patients with various subtypes of malignant lymphoma. Genomic and genetic studies have led to the identification of biological and clinical subgroups of diffuse large B-cell lymphomas with distinct underlying molecular features, divergent activation of oncogenetic pathways, and clinical course. Molecular studies of follicular lymphoma have suggested complex interactions between malignant cells and the surrounding immunological network that could affect disease progression. Moreover, the inflammatory cells of Hodgkin lymphoma have been shown to produce a complex network of cytokines and chemokines that provide a permissive microenvironment for tumor growth. Research into specific biomarkers and signaling pathways of malignant lymphomas might therefore result in the identification of novel targets for future therapeutic strategies. As gene expression profiling techniques are not yet feasible in the clinical laboratory, studies have aimed to translate the findings into more widely applicable techniques that might allow this research to be applied to routine clinical practice. This review focuses on recent advances in translational and clinical research on biomarkers in malignant lymphomas. © 2010 Informa UK, Ltd.

Shanmugam N.,St Georges Healthcare NHS Trust | Boerdlein A.,BIOTRONIK SE and Co. KG | Proff J.,BIOTRONIK SE and Co. KG | Ong P.,St Georges Healthcare NHS Trust | And 5 more authors.
Europace | Year: 2012

AimsUncertainty exists over the importance of device-detected short-duration atrial arrhythmias. Continuous atrial diagnostics, through home monitoring (HM) technology (BIOTRONIK, Berlin, Germany), provides a unique opportunity to assess frequency and quantity of atrial fibrillation (AF) episodes defined as atrial high-rate events (AHRE).Methods and resultsProspective data from 560 heart failure (HF) patients (age 67 ± 10 years, median ejection fraction 27) patients with a cardiac resynchronization therapy (CRT) device capable of HM from two multi-centre studies were analysed. Atrial high-rate events burden was defined as the duration of mode switch in a 24-h period with atrial rates of >180 beats for at least 1 or total of 14 min per day. The primary endpoint was incidence of a thromboembolic (TE) event. Secondary endpoints were cardiovascular death, hospitalization because of AF, or worsening HF. Over a median 370-day follow-up AHRE occurred in 40 of patients with 11 (2) patients developing TE complications and mortality rate of 4.3 (24 deaths, 16 with cardiovascular aetiology). Compared with patients without detected AHRE, patients with detected AHRE>3.8 h over a day were nine times more likely to develop TE complications (P 0.006). The majority of patients (73) did not show a temporal association with the detected atrial episode and their adverse event, with a mean interval of 46.7 ± 71.9 days (range 0194) before the TE complication.ConclusionIn a high-risk cohort of HF patients, device-detected atrial arrhythmias are associated with an increased incidence of TE events. A cut-off point of 3.8 h over 24 h was associated with significant increase in the event rate. Routine assessment of AHRE should be considered with other data when assessing stroke risk and considering anti-coagulation initiation and should also prompt the optimization of cardioprotective HF therapy in CRT patients.© The Author 2011.

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