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1.AbstractBrain Network Models (BNMs) are a family of dynamical systems that simulate whole brain activity using neural mass models to represent local activity in different brain regions that influence each other via a global structural network. Research has been interested in using these network models to explain measured whole brain activity measured via resting state functional magnetic resonance imaging (rs-fMRI). Properties computed over longer periods of simulated and measured data such as average functional connectivity (FC), have shown to be comparable with similar properties estimated from measured rs-fMRI data. While this shows that these network models have similar properties over the dynamical landscape, it is unclear how well simulated trajectories compare with empirical trajectories on a timepoint-by-timepoint basis. Previous studies have shown that BNMs are able to produce relevant features at shorter timescales, but analysis of short-term trajectories or transient dynamics as defined by synchronized predictions from BNM made at the same timescale as the collected data has not yet been conducted. Relevant neural processes exist in the time frame of measurements and are often used in task fMRI studies to understand neural responses to behavioral cues. Therefore, it is important to investigate how much of these dynamics are captured by our current brain simulations. To test the nature of BNMs short term trajectories against observed data, we utilize a deep learning technique known as Neural ODE that based on an observed sequence of fMRI measurements, estimates the initial conditions such that the BNM’s simulation is synchronized to produce the closest trajectory relative to the observed data. We test to see if the parameterization of a specific well studied BNM, the Firing Rate Model, calculated by maximizing its accuracy in reproducing observed short term trajectories matches with the parameterized model that produces the best average long-term metrics. Our results show that such an agreement between parameterization using long and short simulation analysis exists if also considering other factors such as the sensitivity in accuracy with relative to changes in structural connectivity. Therefore, we conclude that there is evidence that by solving for initial conditions, BNMs can be simulated in a meaningful way when comparing against measured data trajectories, although future studies are necessary to establish how BNM activity relate to behavioral variables or to faster neural processes during this time period.

Structural connectivity (SC), the physical pathways connecting regions in the brain, and functional connectivity (FC), the temporal coactivations, are known to be tightly linked. However, the nature of this relationship is still not understood. In the present study, we examined this relation more closely in six separate human neuroimaging datasets with different acquisition and preprocessing methods. We show that using simple linear associations, the relation between an individual’s SC and FC is not subject specific for five of the datasets. Subject specificity of SC-FC fit is achieved only for one of the six datasets, the multimodal Glasser Human Connectome Project (HCP) parcellated dataset. We show that subject specificity of SC-FC correspondence is limited across datasets due to relatively small variability between subjects in SC compared with the larger variability in FC., Author Summary We present evidence that, in most standard datasets, the subject variation in structural connectivity (SC) may be too weak to be reflected in the functional connectivity (FC) variability. However, subject specificity of SC-FC can be captured via fine, multimodally parcellated data because of greater SC variability across subjects. Nonetheless, SC and FC each show a large component that is common across subjects, which sets limitations on the extent of SC-FC subject specificity. Implications of these findings for personalized medicine should be considered. Namely, attention to the quality of processing and parcellation methods is critical for furthering our understanding of the relationship between individual SC and FC.

Models of large-scale brain networks that are informed by the underlying anatomical connectivity contribute to our understanding of the mapping between the structure of the brain and its dynamical function. Connectome-based modelling is a promising approach to a more comprehensive understanding of brain function across spatial and temporal scales, but it must be constrained by multi-scale empirical data from animal models. Here we describe the construction of a macaque (Macaca mulatta and Macaca fascicularis) connectome for whole-cortex simulations in TheVirtualBrain, an open-source simulation platform. We take advantage of available axonal tract-tracing datasets and enhance the existing connectome data using diffusion-based tractography in macaques. We illustrate the utility of the connectome as an extension of TheVirtualBrain by simulating resting-state BOLD-fMRI data and fitting it to empirical resting-state data., Design Type(s)data integration objective • source-based data transformation objective • modeling and simulation objectiveMeasurement Type(s)brain measurementTechnology Type(s)functional magnetic resonance imaging • Diffusion Weighted ImagingFactor Type(s)Sample Characteristic(s)Macaca • brain Machine-accessible metadata file describing the reported data (ISA-Tab format)

Structural connectivity (SC), the physical pathways connecting regions in the brain, and functional connectivity (FC), the temporal co-activations, are known to be tightly linked. However, the nature of this relationship is still not understood. In the present study, we examined this relation more closely in six separate human neuroimaging datasets with different acquisition and preprocessing methods. We show that using simple linear associations, the relation between an individual’s SC and FC is not subject-specific for five of the datasets. Subject-specificity of SC-FC fit is achieved only for one of the six datasets, the multi-modal Glasser HCP parcellated dataset. We show that subject-specificity of SC-FC correspondence is limited across datasets due to relatively small variability between subjects in SC compared to the larger variability in FC.

Brain dynamics span multiple spatial and temporal scales, from fast spiking neurons to slow fluctuations over distributed areas. No single experimental method links data across scales. Here, we bridge this gap using The Virtual Brain connectome-based modelling platform to integrate multimodal data with biophysical models and support neurophysiological inference. Simulated cell populations were linked with subject-specific white-matter connectivity estimates and driven by electroencephalography-derived electric source activity. The models were fit to subject-specific resting-state functional magnetic resonance imaging data, and overfitting was excluded using 5-fold cross-validation. Further evaluation of the models show how balancing excitation with feedback inhibition generates an inverse relationship between α-rhythms and population firing on a faster time scale and resting-state network oscillations on a slower time scale. Lastly, large-scale interactions in the model lead to the emergence of scale-free power-law spectra. Our novel findings underscore the integrative role for computational modelling to complement empirical studies.

Background Indocyanine 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. Methods 252 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. Results In 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

International audience; Recent efforts to model human brain activity on the scale of the whole brain rest on connectivity estimates of large-scale networks derived from diffusion magnetic resonance imaging (dMRI). This type of connectivity describes white matter fiber tracts. The number of short-range cortico-cortical white-matter connections is, however, underrepresented in such large-scale brain models. It is still unclear on the one hand, which scale of representation of white matter fibers is optimal to describe brain activity on a large-scale such as recorded with magneto-or electroencephalography (M/EEG) or functional magnetic resonance imaging (fMRI), and on the other hand, to which extent short-range connections that are typically local should be taken into account. In this article we quantified the effect of connectivity upon large-scale brain network dynamics by (i) systematically varying the number of brain regions before computing the connectivity matrix, and by (ii) adding generic short-range connections. We used dMRI data from the Human Connec-tome Project. We developed a suite of preprocessing modules called SCRIPTS to prepare these imaging data for The Virtual Brain, a neuroinformatics platform for large-scale brain modeling and simulations. We performed simulations under different connectivity conditions and quantified the spatiotemporal dynamics in terms of Shannon Entropy, dwell time and Principal Component Analysis. For the reconstructed connectivity, our results show that the major white matter fiber bundles play an important role in shaping slow dynamics in large-scale brain networks (e.g. in fMRI). Faster dynamics such as gamma oscillations (around 40 Hz) are sensitive to the short-range connectivity if transmission delays are considered. (C) 2016 Elsevier Inc. All rights reserved.

To evaluate the feasibility of gene delivery mediated with diagnostic ultrasound and plasmid DNA (pDNA) encapsulated in gas-filled microparticles (GFMP) in rodent tumor models.This study was performed according to a protocol approved by the regional animal research committee. The model plasmid UT651 (pUT651) that contained the Escherichia coli LacZ gene for beta-galactosidase was used to demonstrate the feasibility of ultrasound-mediated gene delivery in CC531 liver tumors in rats. In preliminary experiments, a single injection of pUT651-containing GFMP was administered intraarterially (n=4) or intravenously (n=6) with simultaneous sonication (color Doppler mode, maximum mechanical index) of the GFMP passing through the capillaries of the tumors. All animals were sacrificed 2-5 days later, and liver tumors were examined for beta-galactosidase expression histochemically. Subsequently, potential medical usefulness of this delivery system was tested in nude mice bearing Capan-1 tumors (adenocarcinoma of the human pancreas) by using the plasmid RC/CMV-p16 (pRC/CMV-p16), which contains tumor suppressor gene p16. The tumor suppressor gene p16 is deleted in Capan-1 cells. Twenty-five tumor-bearing mice were classified into five groups (four to six mice per group, one treatment group, four control groups) at random. All mice were treated once weekly for 5 weeks with intravenous infusion of p16-containing GFMP or control substances with simultaneous tumor sonication with color Doppler mode ultrasound and maximum mechanical index or without ultrasound treatment. The therapeutic effect of p16 was measured as an increase in tumor volume doubling time. Data were analyzed with analysis of variance. Results were considered significant at the 5% critical level (P.05).A clear expression of pDNA was found in tumors in rats treated with a combination of pUT651-containing GFMP and ultrasound; relevant controls showed a significantly lower expression of marker gene. The controlled ultrasound-triggered release of pRC/CMV-p16 from GFMP leads to a strong tumor growth inhibition, which is significant (P.002), compared with that in controls.A combination of GFMP and ultrasound provides an effective approach for nonviral gene therapy-based cancer treatment.

To develop an in vitro assay for studying the feasibility of specific targeting of ultrasound contrast agents (USCAs) for ultrasound diagnostics by employing the parallel plate flow chamber, which provides an environment that mimics some aspects of the in vivo conditions like shear rate and flow effects.USCAs based on air-filled microparticles (MP) were functionalized with specific antibodies using carbodiimide coupling chemistry and characterized by fluorescence activated cell sorter (FACS). The binding experiments were done by subjecting the MP to shear stress as they interact with the target-coated surface of the flow chamber.A successive modification of MP with antibody and the glass surface with antigen was achieved and quantified. The binding studies showed specific attachment of targeted MP to EDB-FN (EDB domain of fibronectin) surface. The binding of MP via nonspecific interactions was minimal. The binding efficiency of antibody-loaded MP is dependent on the applied shear stress. An increase in the wall shear stress resulted in a decrease in binding efficiency. Binding efficiency was found to be correlated with the antibody density and antigen density on the interacting surfaces.The results indicate that the test system developed is reliable for characterizing targeted MP without any additional labeling and can be used as a functionality assay for studying the binding characteristic of USCA with respect to different parameters like density of targeting antibodies on the microparticle surface and of target protein. In addition, the microparticles can be studied in detail under different shear rates and flow conditions. Further studies concerning the in vitro-in vivo correlation will be necessary to further increase the value of this in vitro method.

To evaluate the feasibility of using intravenously administered L-selectin ligand-specific polymer-stabilized air-filled microparticles (MPs) for active targeting of peripheral lymph nodes under normal conditions in animal models.L-selectin ligand-specific MPs and two control substances (immunoglobulin M-isotype MPs and native MPs) were each administered in three conscious mice as a single intravenous bolus injection (1.4 x 10(7) MPs/kg). All mice were sacrificed 30 minutes after administration. Lymph nodes (cervical, inguinal, axillary, popliteal, mesenteric), spleen (positive control), and kidney (blood pool control) were removed and examined for MP-related stimulated acoustic emission (SAE) signals by using harmonic color Doppler ultrasonography (US) in a tank containing degassed water. A second experiment was performed in six anesthetized beagle dogs by using the same MP formulation. Each of the MP formulations was administered in two anesthetized dogs as a single intravenous bolus injection (1 x 10(7) MPs/kg). The popliteal lymph nodes, spleen (positive control), and kidney (blood pool control) were examined in vivo with US for MP-related SAE signals 30 minutes after administration. Fisher exact test for the one-side alternative was used for mouse data analysis.The lymph nodes of all mice (P =.05) and the popliteal lymph nodes of both dogs treated with L-selectin ligand-specific MPs showed clear MP-related SAE signals, whereas the lymph nodes of all mice and the popliteal lymph nodes of four dogs that received the control substances did not show any SAE signals.Use of an intravenously administered L-selectin ligand-specific US contrast agent is feasible for active lymph node targeting in mice and dogs.

The mechanism of action of anticancer chemotherapeutic agents is mainly thought to be due to a direct inhibition of tumor cell proliferation. The enhanced endothelial cell proliferation rate in tumor specimens raised the question whether therapeutic effects of chemotherapeutic agents might be at least partially attributed to an inhibition of tumor angiogenesis. Meanwhile, numerous anticancer chemotherapeutic agents were tested for their antiangiogenic potential. A few agents seem to exert consistent inhibition of tumor angiogenesis even in drug-resistant tumors. Most recent investigations on the antiangiogenic efficacy of different application schedules suggested the use of a tightly spaced, continuous application of appropriate anticancer chemotherapeutic agents. These application schedules are able to exert a strong antiangiogenic effect as indicated by an increase of apoptosis of tumor endothelial cells. Future clinical trials have to determine the therapeutic benefit of novel combination chemotherapy and alternative application schedules.

Stable prostacyclin analogues exert a strong inhibitory effect on lymphogenous as well as haematogenous tumor metastasis in a series of tumor lines. The strong inhibition of metastasis was achieved by repeated once-daily i.g. applications. The mechanism of antimetastatic action is related to the expression of functional IP-receptors (PGI-receptors). As cellular assay systems indicated that the IP-receptor mediated signalling is down-regulated upon continuous exposure to prostacyclin or stable derivatives, it has been questioned whether a mode of drug application with constant plasma drug levels may potentially result in a decrease of the antimetastatic effect. We addressed this question using the stable prostacyclin analogue cicaprost in a disease model by comparing i.g. applications given once daily with a continuous administration of equivalent doses via drinking water. Very similar to our previous investigations in the 13762NF MTLn3 rat mammary carcinoma model, cicaprost administered by i.g. application strongly reduced lung and lymph node metastasis. In contrast, administration of equivalent doses via drinking water leading to lower but constant steady-state plasma levels failed to exert inhibitory effects. Plasma and urine levels of cicaprost were measured with a sensitive radioimmunoassay on the last treatment day. Pharmacokinetic evaluation demonstrated a similar bioavailability of cicaprost in both groups. This result first demonstrates a treatment failure of a prostacyclin derivative in a chronic disease model in association with a continuous drug administration leading to constant plasma levels. A desensitization of receptor signalling by constant plasma levels may be a possible mechanism for treatment failure.

In breast cancer, the survival rate strongly depends on the number of lymph nodes involved. A drug with a specific inhibitory activity on lymph node and organ metastases would therefore be a candidate for adjuvant therapy after surgery. Prostacyclin and its stable analogues have been shown to interfere with certain steps of the metastatic cascade and to inhibit the number of lung colonies after i.v.-inoculation of various tumor cell lines. Our data reveal that cicaprost, a metabolically stable and orally active analogue of prostacyclin, has pronounced antimetastatic effects in a series of spontaneously metastasizing rodent tumors. In the SMT 2a and 13762 MTLn3 mammary carcinomas of the rat, cicaprost given daily from the day of tumor implantation strongly inhibits the number of lung metastases as well as lymph node weights without exerting an effect on the primary tumor. Even starting treatment when palpable primary tumors are present gives a pronounced antimetastatic activity. To demonstrate that cicaprost has an effect on metastases already settled in the respective organ, treatment was started after surgical removal of the primary tumor. In the SMT 2a tumor, a strong inhibition of the number of metastases was shown. Interestingly, a perioperative treatment schedule was also effective in both models used. As primary tumor growth in vivo or proliferation in vitro remained unchanged by cicaprost, its mode of action seems to be related to one or more mechanisms of the metastatic process. In tumor cell lines expressing a functional prostacyclin receptor, stimulated tumor cell migration is inhibited and changes of differentiation status are obvious. In conclusion, cicaprost strongly inhibits lymph node and organ metastases of spontaneously metastasizing rodent mammary tumors with a mode of action different from cytostatic or antihormonal drugs.

Using 15 rats with collagen-induced arthritis (30 joints) and 7 control rats (14 joints), we correlated the intensity of near-infrared fluorescence (NIRF) of the nonspecific dye tetrasulfocyanine (TSC) with magnetic resonance imaging (MRI), histopathology, and clinical score. Fluorescence images were obtained in reflection geometry using a NIRF camera system. Normalized fluorescence intensity (INF) was determined after intravenous dye administration on different time points up to 120 min. Contrast-enhanced MRI using gadodiamide was performed after NIRF imaging. Analyses were performed in a blinded fashion. Histopathological and clinical scores were determined for each ankle joint. INF of moderate and high-grade arthritic joints were significantly higher (p

More than a decade ago, prostacyclin, a dienoic bicyclic eicosanoid derived from the metabolism of arachidnoic acid, was found to possess potent inhibitory effects on tumor cell metastasis. Thereafter, several laboratories demonstrated the metastasis-suppressive activity of prostacyclin in a wide spectrum of tumor types. Due to the short half-life of prostacyclin, researchers have focused on looking for stable prostacyclin analogues which have extended half lives and increased bioavailabilities. Cicaprost, among other prostacyclin analogues tested, has been demonstrated, like prostacyclin, to effectively inhibit metastasis in several different animal models (i.e., both experimental and spontaneous metastasis models). Prostacyclin as well as cicaprost prevent not only hematogenous, but also lymphatic metastasis. Furthermore, these compounds also inhibit the growth of established micrometastases after removal of the primary tumors. Mechanistic studies revealed that the antimetastatic effects of prostacyclin and its analogues are more related to their interference with tumor cell-host interactions (such as tumor cell induced platelet aggregation, tumor cell adhesion to endothelial cells and subendothelial matrix, tumor cell induced endothelial cell retraction, etc.) than their direct inhibition of the growth of primary tumors. The potent and widespread metastasis-retarding effects of prostacyclin and its stable analogues in animal tumor models warrant their clinical trial in treating human cancer patients and preventing metastasis.

Prostacyclin and its stable analogues have been shown to interfere specifically with certain steps of the metastatic cascade. The antimetastatic activity of the stable prostacyclin analogue Cicaprost (Schering AG) on haematogenous metastasis in a series of tumours in rats and mice has been well established. In order to test the effect of Cicaprost on lymphogenous metastasis we chose the metastatic cell clone MTLn3 derived from the 13762NF rat mammary carcinoma. The effect of Cicaprost on prevention of lung metastasis, lymph node metastasis and primary tumour growth was investigated. Cicaprost given in daily doses of 0.01, 0.03 and 0.1 mg/kg orally, reduced the number of lung metastases in a dose-dependent manner. Whereas the median number of lung metastases in the controls was greater than 1000, Cicaprost at a dose of 0.1 mg/kg reduced the number of lung metastases to between 11 and 100. The weight of the ipsilateral axillary lymph nodes was diminished by Cicaprost to 30-50% of controls. Moreover, metastasis to the contralateral axillary lymph node was completely inhibited by Cicaprost at all three doses tested. Cicaprost did not influence the growth rate of the MTLn3 cell clone implanted into the mammary fat pad or the weight of the primary tumour at the end of treatment. In conclusion, in addition to its dose-dependent effect on haematogenous metastasis, Cicaprost strongly inhibits lymph node metastasis.

The blood pool agent indo-cyanine green (ICG) has been investigated in a prospective clinical study for detection of rheumatoid arthritis using fluorescence imaging. Temporal behavior as well as spatial distribution of fluorescence intensity are suited to differentiate healthy and inflamed finger joints after i.v. injection of an ICG bolus.

The dye ICG was investigated in a clinical study for evaluation of rheumatoid arthritis using fluorescence imaging. Second moments of correlated time series of fluorescence intensities were analysed to differentiate healthy subjects from diseased.

The blood pool agent indo-cyanine green (ICG) has been investigated for early detection of rheumatoid arthritis using fluorescence imaging. Different distributions of fluorescence intensity are found for healthy and inflamed finger joints after i.v. injection of an ICG bolus .

We have developed a flying-spot scanner for fluorescence imaging of rheumatoid arthritis in the near infrared (NIR) spectral range following intravenous administration of contrast agents. The new imaging system has been characterized with respect to linearity, dynamic range and spatial resolution with the help of fluorescent phantoms. In vivo experiments were performed on an animal model of rheumatoid arthritis. Finally, NIR-fluorescence images of early stages of joint inflammation have been compared with findings from contrast enhanced MR imaging and histology.

Different methods of manufacturing permitted the production of air-filled PBCA microparticles (af-pbca-mp) with different physical properties such as size and wall thickness. These differences led to distinctions with respect to mechanical stability and, at the same time, to different levels of biochemical stability when incubated in biofluids. Microparticles, designed as they are to be mechanically more stable (composed of larger nanoparticles resulting in thicker shell wall, no surface hydrolysis), persist longer under in vitro conditions in biofluids such as serum, plasma and whole blood than do the more fragile ones. It was possible when using the measurement of ultrasound attenuation to characterize af-pbca-mp degradation with respect to the disappearance of the ultrasound properties of the particles and therefore to find out how long different formulations can be expected to be active as contrast agents under simulated in vivo conditions. The present examination showed that using either serum, plasma or whole blood leads to results with the same tendencies in terms of the stability and durability of af-pbca-mp in the media, mimicking in vivo conditions. It was thus possible to validate successfully the use of either serum or plasma as substitutes for whole blood. Further studies dealing with the in vitro in vivo correlation will be needed to find out if the situation in this in vitro assay corresponds to the situation in the body.

Background: Purpose of the study was to detect early breast cancer and its precursors by in vivo optical molecular imaging in an animal model. Material and methods: Females of the transgene mouse strain WAP-TNP8 develop non-invasive and consequently invasive tumours of the mammary glands due to specific expression of the viral SV40 large tumour antigen induced by lactation. The molecular target for imaging was extradomain-b fibronectin (EDB-FN), which is associated with tumour angiogenesis. The optical probe was designed as a compound of an anti-EDB-FN antibody fragment and a near-infrared fluorescent dye. 30h after intravenous injection of the contrast agent, optical imaging was performed using a pulsed Laser system for excitation and an intensified CCD-camera to record fluorescence images. After optical molecular imaging all animals were sacrified and the tumours were examined histologically. Results: Initiated transgene female animals developed palpable masses of the mammary gland within 6 months (median 4 months). Imaging was performed in 5 animals with a total of 9 tumours (diameter 2–7mm, median 4mm). Applying optical molecular imaging 8 of 9 tumours were detected. The urogenital tract was contrasted unspecifically. Histological examination proved invasive epithelial tumours of the mammary gland in all cases. Conclusion: Breast cancer can be detected in vivo by near-infrared fluorescence molecular imaging targeting neoangiogenesis in a transgene mouse-model.

Molecular imaging requires, not only the identification of an appropriate marker, but also its quantitative analysis. We used the Sensitive Particle Acoustic Quantification (SPAQ) technology - a novel ultrasound technique - for detection and quantification of cell adhesion molecules in isolated tissue and in live animals. By conjugating gas-filled microparticles (MPs) with antibodies to intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1), we were able to depict and quantify ICAM-1 and VCAM-1 in isolated brain and spinal cord from rats with autoimmune encephalomyelitis (EAE), an established inflammatory disease model of human multiple sclerosis (MS). Depiction and quantification of specific MPs were also feasible in living animals with AT-EAE with similar results. After treatment with methylprednisolone, the measured number of targeted anti-ICAM-1 and VCAM-1-MPs was significantly lower (P0.01) compared to untreated animals demonstrating the high sensitivity of this imaging technique. Depending on the antibody linked to the surface of the MPs, the technique can be used to quantify the expression of any accessible antigen expressed on the luminal surface of endothelial cells and is therefore a promising tool for the non-invasive and dynamic assessment of disease-related molecules.

The present study described a new strategy to examine the interaction between the targeted ultrasound contrast agent (USCA) and its target under flow conditions with a surface acoustic wave (SAW) transducer. The sensing principle is based on the measurement of the phase change on the sensing element upon the binding of specific biomolecules. Love-wave biosensor array was consisting of sensor elements and reference elements. The sensor elements have been prepared by coating the sensor surface with tumor marker EDB-fibronectin by means of SAM technique and carbodiimide chemistry. Reference elements were left blank or coated with fibronectin and used to eliminate thermal drift, unspecific binding, and turbulence from injection of liquids by calculating the differential phase shift with respect to the sensor elements. The binding of targeted USCA to the sensor surface was constantly recorded by monitoring the phase shift on the sensor element. The binding of targeted USCA generated a high phase shift on the sensor elements, but almost no change on the reference elements. Control experiments using non-targeted and isotype-targeted USCA confirmed the specificity of binding due to anti-EDB-fibronectin scFv-antibody-fragment-EDB-fibronectin antigen interaction. The suitability of the SAW technique to monitor the specific binding behavior of targeted micron-sized USCA in real time has been well established.

Advances in imaging provide new insights into the pathophysiol-ogy of many diseases. Established imaging technologies such as MRI, CT, PET, and ultrasound are routinely applied to determine features of tumor blood vessels that distinguish them from normal blood vessels. These techniques yield information on blood flow, blood volume, and vessel permeability. Often, an intravenously injected imaging contrast agent without affinity to a specific target structure is applied to enable detection of malignant lesions. One of the emerging innovations in diagnostic imaging is the evolution of molecular imaging techniques. Molecular imaging is a noninvasive approach to determine the expression of indicative marker molecules of the tumor angiogenesis process. Meanwhile, this approach has been established for all imaging modalities and may further improve sensitivity of diagnostic tumor imaging. Another goal is to provide information with respect to drug treatment monitoring and therapeutic vascular targeting strategies.

Fluorescence imaging in the near-infrared range following intravenous administration of contrast agents has been investigated as a new tool for detection of inflammatory joint diseases. Our study reveals that NIR dyes accumulate in inflammatory joints.

Background Fluorescence optical imaging (FOI) is a novel imaging technology. It detects hypervascularisation of inflamed joints and tissues in both hands using indocyanine green (ICG) as fluorophore. Objectives In this study, FOI was compared to low-field MRI and musculoskeletal ultrasound (US) in patients with early rheumatoid arthritis (RA). Methods Thirteen patients (9 female; mean age 54±15 yrs, range 26-75) with the diagnosis of early RA were enrolled. Low-field MRI (under application of 0.2 mmol/kg BW Dotarem®) and US (grey-scale (GSUS) as well as power-Doppler (PDUS) mode) of the clinically more affected hand were performed. Both methods were evaluated according to the OMERACT criteria. After informed consent, all patients were examined by the FOI device Xiralite© (mivenion GmbH, Berlin) using ICG as fluorophore (ICG-Pulsion® 0.1 mg/kg BW bolus I.V., 6 minutes examination time). Images were interpreted in three defined phases of increased signal intensity (ISI) in the finger tips: early (P1, prior to strong ISI in the finger tips), intermediate (P2, during ISI in the finger tips), and late phase (P3, after decreasing of ISI in the finger tips) [1]. Sensitivity and specificity for synovitis were calculated using MRI as reference. Furthermore, interclass correlation coefficients (ICC) were calculated between all three imaging methods. Results In total, 104 joints (MCP n=52, PIP n=52) were evaluated. For all finger joints, FOI reached a sensitivity of 88% and specificity of 57% using MRI as reference. In detail, sensitivity of 70% and specificity of 81% was calculated for the MCPs (n=52), and sensitivity of 96% and specificity of 41% for the PIPs (n=52) (Table 1). The ICCs between MRI and FOI were 0.77 for the MCPs and 0.79 for the PIPs. The ICCs between US and FOI were 0.79 for the MCPs and 0.73 for the PIPs (Table 2). Conclusions With MRI as reference, the novel FOI method seems to be very sensitive in the detection of synovitis, but not very specific. There was a high sensitivity especially for the PIP joint evaluation, with poor specificity, though. In contrast, MCP joint evaluation by FOI was much more specific. There were comparable good correlations between FOI and MRI as well as between FOI and US. Hence, FOI might be a helpful tool in the screening of patients with suspected early RA. References Werner SG, Langer EH, Ohrndorf S, et al. Inflammation assessment in patients with arthritis using a novel in vivo fluorescence optical imaging technology.Ann Rheum Dis. 2011 Oct 12. [Epub ahead of print] Disclosure of Interest S. Ohrndorf Grant/Research support from: Arthromark Research Support, M. Krohn: None Declared, S. Werner Grant/Research support from: Pfizer Research Support, M. Bahner: None Declared, M. Schirner: None Declared, B. Reiche: None Declared, S. Schneider: None Declared, L. Braum: None Declared, G. Burmester: None Declared, B. Hamm: None Declared, K.-G. Hermann: None Declared, M. Backhaus Grant/Research support from: Pfizer Research Support

Background Assessment of arthritis using fluorescence optical imaging (FOI) in combination with the fluorophore indocyanine green (ICG) is now clinically established [1]. Beyond imaging of inflammation, FOI also provides the opportunity to monitor drug targeting of biological therapeutics into inflamed joints. Quantitative information of drug targeting would allow for patient selection and individual treatment schedules. Objectives We report the first synthesis of etanercept-ICG-conjugates and the quantitative monitoring of drug targeting into inflamed joints of collagen II induced arthritis using a modified fluorescent camera system (Xiralite). Methods Inflammatory arthritis was induced by twice injections of bovine collagen II (day 0, day 7) in female Lewis rats. Rats were monitored for joint swelling, pain, redness and mobility (score 0 to 3). The TNFa binding protein etanercept (Enbrel®, Pfizer) was chemically conjugated with an ICG derivative suited for labeling of proteins. The etanercept-6S-ICG (Eta-6S-ICG) conjugate was photophysically characterized and tested for binding affinity The fluorescence camera system Xiralite (mivenion GmbH, Germany) [1] was modified to enable imaging of rats. On day 14 after first injection of collagen, Eta-6S-ICG (n=6), IgG-6S-ICG (n=3), or the inflammation-targeted macromolecule polyglycerolsulfate-6S-ICG (dPGS-6S-ICG, n=5) [2] were s.c. or i.v. injected in a dose of 10 nMol/kg b.w. Fluorescence measurement was performed before and 1 h, 3 h, 24 h and 48 h after injection. Fluorescence intensity (FI) was measured in ROI over the tibio-tarsal and interphalangeal articulations and compared with healthy reference ROI. In addition, targeting was studied in rat tissues 3 or 24 h post injection of Eta-6S-, IgG-6S- or dPGS-6S-indocarbocyanine conjugates using fluorescence histology. Results Binding affinity of etanercept was not attenuated by chemical conjugation with 6S-ICG. Eta-6S-ICG exerts high fluorescence quantum yield compared with ICG. FI was detected already 24 hours after administration of Eta-6S-ICG and further increased until 48 hours after injection. Significant FI at 48 hours after injection of Eta-6S-ICG was measured in tibio-tarsal joints (score 1: 15.8±2.9; score 3: 31.0±4.6) while FI in interphalangeal joints was low (score 1: 6.3±1.0; score 3: 7.7±1.2). In contrast, dPGS-6S-ICG exhibited high FI in both tibio-tarsal joints (score 1: 23.5±4.9; score 3: 69.8±17.5) and interphalangeal joints (score 1: 20.9±5.8; score 3: 37.0±4.7). Both Eta-6S- ICG and dPGS-6S-ICG show strong targeting to inflamed synovial tissue and cartilage compared with IgG-6S-ICG. Conclusions FOI and labeling of macromolecular therapeutics with novel ICG derivatives provide a novel rationale for sensitive and quantitative monitoring of arthritis therapy. Further studies have to determine the effect of varying molecular size on the degree of targeting of inflamed joints. References Werner S et al. Inflammation assessment in patients with arthritis using a novel in vivo fluorescence optical imaging technology. Ann Rheum Dis doi:10.1136/ard.2010.148288. Licha K et al. Fluorescence imaging with multifunctional polyglycerol sulfates: novel polymeric near-IR probes targeting inflammation. Bioconjug Chem; doi:10.1021/bc2002727 Disclosure of Interest P. Welker Employee of: mivenion GmbH, K. Licha Shareholder of: mivenion GmbH, I. Gemeinhardt: None Declared, M. Bahner Shareholder of: mivenion GmbH, J. Berger Employee of: mivenion GmbH, D. Mangoldt Employee of: mivenion GmbH, J. Schnorr: None Declared, M. Schirner Shareholder of: mivenion GmbH

Background Diagnostic imaging, including ultrasound and MRI is routinely used in joint diseases. Besides initial diagnosis of the disease, imaging is also of strong interest for monitoring of treatment response. In this regard, semi-quantitative scores, like the RAMRIS or the US7 – score, aim at measuring disease activity. Most recently, fluorescence optical imaging (FOI) with the Xiralite® system became clinically available for diagnostic imaging of inflammation in the hands [1]. So far, a quantitative method for measuring disease activity has not been published. Objectives We first report a method for an automated, computer-based algorithm for real-time, quantitative analysis of FOI images. Methods 15 FOI standard exams were randomly selected from the multicenter OPERA1 trial (rheumatoid arthritis = 7; psoriatic arthritis = 8). These and 6 exams from normal individuals without clinical symptoms were calculated. Composite images of the first 240 seconds were generated. Using dedicated parameters of the histograms, automatic extraction of left and right hands from the image background was performed. After the extraction, the investigational algorithm separated the hands from the forearm in a standardized manner by using a multiple of the length of the middle finger. Next, a threshold in the fluorescence intensity curve was set to discriminate and measure high and low intensity areas in patients and healthy individuals. Next, high intensity areas of patients were compared with the mean value of normal individuals which was defined as reference value. Disease activity (DACT) is expressed as signal intensity (SI) (threshold to max patient/mean SI (threshold to max)healthy. DACT in healthy individual equals 1 which relates to an area of high intensity of 3.6%. Results 21 left and 21 right hands were correctly extracted from the auto-scaled composite image of the first 240 seconds. The intra-individual variation of the extraction procedure measured as high intensity area in three consecutive procedures was Conclusions Automatic, computer-based image analysis of FOI using dedicated software is technically feasible and offers high reproducibility. Measurement of areas of high signal intensity may provide a reliable quantitative readout for inflammatory activity. Varying doses of ICG do not have an obvious impact on auto-scaled composite images or calculated values. Further clinical investigations have to determine the agreement with other clinical measures (e.g. DAS28, ACR). References Werner SG et al. Inflammation assessment in patients with arthritis using a novel in vivo fluorescence optical imaging technology. Ann Rheum Dis 2011: in press Disclosure of Interest M. Schirner Shareholder of: mivenion, Employee of: mivenion, M. Cziumplik Employee of: mivenion, M. Bahner Shareholder of: mivenion, Employee of: mivenion, J. Berger Employee of: mivenion

Background Fluorescence optical imaging (FOI) with the Xiralite® system is clinically available for diagnostic imaging of inflammation and has been shown to be a suitable tool to assess treatment response in subjects with RA and PsA. Changes in FOI are measured using the semi-quantitative fluorescence optical imaging activity score (FOIAS) which allows for a low inter-reader variability 1 . Most recently, an automatic, computer-based image analysis of FOI (DACT) has been described and validated in healthy subjects 2 . Objectives To evaluate an automatic computer-based analysis of FOI in patients with RA or PsA under treatment. Methods 30 patients with rheumatoid (RA) or psoriatic (PsA) arthritis were examined before starting treatment (visit 1) and at follow-up (visit 2). Treatment response was assessed using DAS28, cFOIAS and the automated calculated DACT. First, 3 readers analyzed all 60 image data sets individually. For articular location of increased signal intensities (ISI) the FOIAS was used. For extraarticular location the signals were graded semiquantitatively on a scale of 0 to 2. These values were added to a single number representing the overall fluorescence signal intensity of the hands (cFOIAS). For DACT composite images were generated automatically. Using dedicated parameters of the histograms, automatic extraction of the hands from the image background was performed by the computer. The algorithm separated the hands from the forearm in a standardized manner by using a multiple of the length of the middle finger. A threshold in the fluorescence intensity curve was set to discriminate high and low intensity areas. The area of high intensity was calculated and the values of each patient were divided by the 95th percentile of normal individuals which was defined as reference value. DACT was expressed as high signal intensity area patient / healthy reference. DACT in healthy individuals equals 1. Then cFOIAS and DACT values were compared. Results 60 left and 60 right hands were correctly extracted from the auto-scaled composite image of the first 240 seconds. The intra-individual variation of the extraction procedure measured as intensity area of the hand in the consecutive procedures was 1.1 % + 1.0 (range: 0.04 – 4.9). cFOIAS scores strongly correlate with automated calculated DACT (0.86 / reader 1, 0.84 / reader 2 and 0.85 / reader 3). Agreement of declining DAS28 with declining cFOIAS was found in 16/30 (reader 1), 17/30 (reader 2) and 15/30 (reader 3) treatment courses. Agreement of declining DAS28 with declining DACT was found in 16/30 treatment course. Conclusions This first clinical trial in patients with RA or PsA under treatment with follow-up FOI exams demonstrates that automatic, computer-based image analysis of FOI to calculate DACT values is technically feasible, offers high reproducibility and high agreement with cFOIAS score reading, while agreement of DACT value with DAS28 was only moderate. Even very low changes of the DACT value can be measured and considered as statistically significant. References Werner SG et al. Indocyanine Green Enhanced Optical Imaging Using for Monitoring of Treatment Response. Arthritis & Rheumatism 2011: 63 (10); S73 Schirner M. et al. Methods for automated, computer-based quantitative assessment of fluorescence optical imaging. Ann Rheum Dis 2012;71(Suppl3):711 Disclosure of Interest M. Bahner Shareholder of: mivenion GmbH, Employee of: mivenion GmbH, S. Werner: None Declared, M. Cziumplik Employee of: mivenion GmbH, J. Berger Employee of: mivenion GmbH, H.-E. Langer: None Declared, M. Schirner Shareholder of: mivenion GmbH, Employee of: mivenion GmbH

Spontaneously hypertensive rats (SHR) of the Okamoto strain with blood pressure above 161 mmHg and SHR with blood pressure levels of less than 160 mmHg were treated with oral doses of aspirin (100 mg kg-1) for three days. Whereas the blood pressure of SHR with blood pressure above 161 mmHg was decreased by aspirin, the blood pressure of SHR below 160 mmHg was increased by aspirin. The extent and direction of blood pressure change by aspirin was strongly correlated with the blood pressure of SHR before treatment (r = -0.88). The effect of aspirin supports an important role for endogenous prostanoids in the regulation of blood pressure of SHR.

We investigated the effect of cisplatin given at different treatment intervals on growth of the s.c.-implanted M 5076 reticulum sarcoma and the number of liver metastases at the end of the experiment (day 24). The later the treatment was started, the smaller was the tumour-inhibiting effect of cisplatin on primary tumour growth. Initiation of cisplatin treatment before day 14 after tumour implantation inhibited liver metastases completely. Treatment starting from day 14 or later did not influence the number of liver metastases. With regard to the clinical situation, the data imply that in the search for new leads in anticancer compounds, experimental conditions should concentrate on the inhibition of metastatic tumour growth.

Investigations on mechanisms of metastatic tumour spread revealed a role for compounds that inhibit tumour dissemination at the time of hematogenous dissemination. The platelet aggregation inhibitor prostacyclin and its stable analogues were shown to inhibit tumour-cell-induced platelet interaction as well as tumour cell adhesive mechanisms. This study concentrates on the effect of the stable prostacyclin analogue cicaprost: 5-{(E)-(1S, 5S, 6S, 7R)-7-hydroxy-6-[(3S, 4S)-3-hydroxy-4-methylnona-1,6-diinyl]-bicyclo[3,3,0]octan-3-ylidene}-3-oxapentanoic acid (Schering AG), as cyclodextrin clathrate, on spontaneous tumour metastases of two different carcinomas of the rat. In Cop rats bearing spontaneously metastasizing R 3327 MAT Lu prostate carcinomas, cicaprost (1.0 mg/kg p.o. daily) inhibited the number of lung metastases by about 80%, whereas the lower doses (0.1 and 0.5 mg/kg) exhibited borderline efficacy. In female Wistar-Furth rats bearing s.c. implanted SMT 2A mammary carcinomas, spontaneously metastasizing into regional lymph nodes and lungs, cicaprost (0.1, 0.5 and 1 mg/kg) p.o. daily exhibited a dose-dependent inhibition of the number of lung metastases. Five out of ten animals treated by 1 mg/kg were free of visible lung metastases. The weight of the axillary lymph node was significantly reduced by the 1 mg/kg dose of cicaprost, whereas lower doses has no effect on the weight of the lymph nodes. The growth of the primary tumour was not influenced by cicaprost in the R 3327 MAT Lu prostate carcinoma nor in the SMT 2A mammary carcinoma in the dose range tested. In conclusion, the stable prostacyclin analogue cicaprost exhibits a strong antimetastatic action in two metastasizing tumours of the rat and interferes with the steps not only of haematogenous, but also of lymphogenous metastasis.