Interactions of tumor cells with lymphatic vessels are of paramount importance for tumor progression, however, the underlying molecular mechanisms are poorly understood. Whereas enlarged lymphatic vessels are frequently observed at the periphery of malignant melanomas, it has remained unclear whether intratumoral lymphangiogenesis occurs within these tumors. Here, we demonstrate the presence of intratumoral lymphatics and enlargement of lymphatic vessels at the tumor periphery in vascular endothelial growth factor (VEGF)-C-overexpressing human melanomas transplanted onto nude mice. VEGF-C expression also resulted in enhanced tumor angiogenesis, indicating a coordinated regulation of lymphangiogenesis and angiogenesis in melanoma progression. The specific biological effects of VEGF-C were critically dependent on its proteolytic processing in vivo.

Adhesive interactions of leukocytes and endothelial cells initiate leukocyte migration to inflamed tissue and are important for immune surveillance. Acute and chronic inflammatory diseases show a dysregulated immune response and result in a massive efflux of leukocytes that contributes to further tissue damage. Therefore, targeting leukocyte trafficking may provide a potent form of antiinflammatory therapy. Leukocyte migration is initiated by interactions of the cell adhesion molecules E-, L-, and P-selectin and their corresponding carbohydrate ligands. Compounds that efficiently address these interactions are therefore of high therapeutic interest. Based on this rationale we investigated synthetic dendritic polyglycerol sulfates (dPGS) as macromolecular inhibitors that operate via a multivalent binding mechanism mimicking naturally occurring ligands. dPGS inhibited both leukocytic L-selectin and endothelial P-selectin with high efficacy. Size and degree of sulfation of the polymer core determined selectin binding affinity. Administration of dPGS in a contact dermatitis mouse model dampened leukocyte extravasation as effectively as glucocorticoids did and edema formation was significantly reduced. In addition, dPGS interacted with the complement factors C3 and C5 as was shown in vitro and reduced C5a levels in a mouse model of complement activation. Thus, dPGS represent an innovative class of a fully synthetic polymer therapeutics that may be used for the treatment of inflammatory diseases.anti-inflammatory drug | complement inhibition | multiple target binding | multivalent selectin inhibitor | synthetic polymer

Brain function is thought to emerge from the interactions among neuronal populations. Apart from traditional efforts to reproduce brain dynamics from the micro-to macroscopic scales, complementary approaches develop phenomenological models of lower complexity. Such macroscopic models typically generate only a few selected-ideally functionally relevant-aspects of the brain dynamics. Importantly, they often allow an understanding of the underlying mechanisms beyond computational reproduction. Adding detail to these models will widen their ability to reproduce a broader range of dynamic features of the brain. For instance, such models allow for the exploration of consequences of focal and distributed pathological changes in the system, enabling us to identify and develop approaches to counteract those unfavorable processes. Toward this end, The Virtual Brain (TVB) (www.thevirtualbrain.org), a neuroinformatics platform with a brain simulator that incorporates a range of neuronal models and dynamics at its core, has been developed. This integrated framework allows the modelbased simulation, analysis, and inference of neurophysiological mechanisms over several brain scales that underlie the generation of macroscopic neuroimaging signals. In this article, we describe how TVB works, and we present the first proof of concept.

BackgroundIndocyanine green (ICG)-enhanced fluorescence optical imaging (FOI) is an established technology for imaging of inflammation in animal models. In experimental models of arthritis, FOI findings corresponded to histologically proven synovitis. This is the first comparative study of FOI with other imaging modalities in humans with arthritis.Methods252 FOI examinations (Xiralite system, mivenion GmbH, Berlin, Germany; ICG bolus of 0.1 mg/kg/body weight, sequence of 360 images, one image per second) were compared with clinical examination (CE), ultrasonography (US) and MRI of patients with arthritis of the hands.ResultsIn an FOI sequence, three phases could be distinguished (P1–P3). With MRI as reference, FOI had a sensitivity of 76% and a specificity of 54%, while the specificity of phase 1 was 94%. FOI had agreement rates up to 88% versus CE, 64% versus greyscale US, 88% versus power Doppler US and 83% versus MRI, depending on the compared phase and parameter. FOI showed a higher rate of positive results compared to CE, US and MRI. In individual patients, FOI correlated significantly (p<0.05) with disease activity (Disease Activity Score 28, r=0.41), US (r=0.40) and RAMRIS (Rheumatoid Arthritis MRI Score) (r=0.56). FOI was normal in 97.8% of joints of controls.ConclusionICG-enhanced FOI is a new technology offering sensitive imaging detection of inflammatory changes in subjects with arthritis. FOI was more sensitive than CE and had good agreement with CE, US in power Doppler mode and MRI, while showing more positive results than these. An adequate interpretation of an FOI sequence requires a separate evaluation of all phases. For the detection of synovitis and tenosynovitis, FOI appears to be as informative as 1.5 T MRI and US.

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