Clinical Hemorheology and Microcirculation

Magnetocardiography (MCG) has been proposed as a non-invasive and functional technique with high accuracy for diagnosis of myocardial ischemia.

This study sought to develop a novel scoring system of MCG for predicting the presence of significant obstructive coronary artery disease (CAD).

In a training set of 108 subjects, predictors of ≥70% stenosis in at least one major coronary vessel were prospectively identified from MCG variables. The final model was then retrospectively validated in a separate set of 45 subjects.

In the multivariable logistic regression, among those in the training set, elevated scores were predictive of ≥70% stenosis in all subjects (OR: 40.85; 95% CI: 6.28–265.90; p < 0.001). In the validation set, the score had an area under the receiver-operating characteristic curve of 0.91 (p < 0.001) for ≥70% stenosis. At an optimal cutoff, the score had 89% sensitivity, 77% specificity, 74% positive predictive value (PPV), 91% negative predictive value (NPV), and 82% accuracy for ≥70% stenosis. Partitioning the score into three levels of predicted risk, 91% of subjects could be identified or excluding CAD (81% PPV and 84% NPV).

We described an MCG score with high accuracy for predicting the presence of anatomically significant CAD.

Remote ischemic preconditioning (RIPC) has been demonstrated to induce potent cardioprotection in individuals experiencing coronary ischemia. A protocol combining limb ischemia and electronic muscle stimulation of the ischemic skeletal muscle (RIPC+), performed in advance of coronary artery occlusion, was superior in terms of infarct size reduction when compared to RIPC alone.

This study was performed to evaluate the benefit of RIPC + in humans compared to a standard RIPC protocol and a control group. Patients with a single vessel coronary artery disease undergoing elective PCI were eligible to participate in this study. ST-segment elevations from an intracoronary ECG during 3 brief episodes of coronary artery balloon occlusions/dilatation were used as the primary endpoint.

ST-elevations significantly declined from the first to the third angioplasty in the control but remained at the same level in the RIPC and RIPC+groups. The RIPC group was characterized by the lowest ST-segment shift during coronary ischemia, which was comparable to coronary balloon occlusion number 3 in the control group, indicating successful preconditioning by the conventional RIPC method. In contrast, ST segment elevations were significantly higher in the RIPC + group. Troponin levels taken 24 h after the study procedure were significantly lower in the RIPC when compared to the control and the RIPC + group.

Our results again confirm the feasibility of remote ischemic preconditioning in patients undergoing coronary angioplasty. According to our results ischemia combined with electronic skeletal muscle stimulation was not superior to conventional RIPC cycles (skeletal muscle ischemia alone).

Contrast-induced acute kidney injury (CI-AKI), a potentially life-threatening complication of iodinated contrast media in patients with impaired renal function, has attracted increasing attention in recent years. There is overwhelming evidence that the most important pre-disposing factor for a contrast-medium induced nephropathy is the pre-existence of a renal impairment.

The registry was performed as a part of a quality management project in the Dresden-Friedrichstadt heart catheter laboratory. In compliance with the Declaration of Helsinki/Somerset West, 9,026 patients were included between 2010 and 2015. 100 patients of these were participants in a chronic dialysis program. All patients were dialyzed on the day before angiography. In all patients a coronary angiography, in 28 patients a stent implantation and in 12 patients a surgical reconstruction had to be performed. Prior to the intervention and one, two and three days thereafter the serum creatinine was measured.

Up to the third day after application of the iodinated contrast medium no significant changes of the serum creatinine (baseline value: 423.3±42.6μmol/l) occurred (ANOVA for repeated measures: p = 0.507). On average, a slight decrease of the serum creatinine was found.

All patients remained in their routine dialysis-program. 18 out of 100 died during the next three months after the procedure.

The study revealed that the coronary angiography using Iodixanol as iodinated contrast medium did not result in an increase of serum creatinine, which was drastically elevated in these patients before application of the iodinated contrast medium.

Chronic venous disease (CVD) is extremely common worldwide. The prevalence is increasing with age and is associated with a reduced quality of life, particularly in relation to pain, physical function and mobility. Symptomatic chronic venous insufficiency (CVI) with venous ulcer at its’ endpoint, indicates interventional surgery to cure venous reflux therewith promoting wound healing and preventing recurrence. To our knowledge up to now no coherent study has been undertaken in patients with CVI who underwent an open venous surgery concerning complications, venous hemodynamics and perioperative symptomology in one study population. This was undertaken in our retrospective, single-centre, consecutive case-control study in a single patient population of a university clinic in northern Germany. Part I covers postoperative complications in relation with co-morbidities, co-medication and clinical presentation. Part II will focus on pre- and postoperative hemodynamics and evolution of symptoms.

Records of n = 429 (467 extremities) patients from 2009–2013 treated with open surgery were analysed. Number and type of complication were evaluated with regards to demographic parameters, co-existing medical conditions and procedure related aspects. Complications were grouped as no events (NE), neglectable adverse events (NAE), non-neglectable adverse events (NNAE) and severe (life-threatening) adverse events (SAE).

In 467 extremities of 429 patients with CVI 130 (27,84%) postoperative complications were observed after open surgery, thereof 64 (13,7%) NAE, 66 (14,14%) NNAE and 0 SAE. 29 (6,76%) patients developed a postoperative surgical site infection, thereof 4 (0,9%) with consecutive septicaemia. Except one case with nerval lesion and paraesthesia and hypoesthesia not resolving after 12 months all complications resolved within surveillance time span of 12 months. Patients developing NAE had a higher BMI (p = 0.003), were more likely to have diabetes mellitus (p < 0.001), and co-morbidities leading to the intake of anti-platelet or anticoagulation drugs (p < 0.001). Metabolic syndrome (p < 0.001) and anti-platelet or anticoagulation (p < 0.001) could be defined as independent risk factors for the development of complications. Patients receiving open surgery of small saphenous veins had 8 times higher risk of calf muscle venous thrombosis (p = 0.001).

Patients with a metabolic syndrome or receiving anti-platelet therapy or anticoagulation medication should undergo open venous surgery under hospital conditions with routine postinterventional surveillance visits. Patients undergoing an open surgery of SSV are definite candidates for postoperative subcutaneous heparin thromboprophylaxis. In general stripping below knee increases the risk of postoperative sensory deficit. This resolves in almost all patients within one year.

Allograft rejection (AR), chronic allograft injury (CAI) and acute tubular necrosis (ATN) can lead to renal allograft dysfunction after kidney transplantation. Interstitial fibrosis/tubular atrophy (Banff classification 2005) describes chronic allograft injury with no specific etiology, thus explaining the common final endpoint of various (immunologic and non immunologic) etiologies. The aim of this study was to evaluate correlations between the Doppler sonographic RI-values and histopathological changes of renal allografts biopsies during rejection, acute tubular necrosis and chronic allograft injury as well as the influence of donor and recipient features on the intrarenal RI-values.

102 allograft biopsies and ultrasound reports of 69 patients with kidney transplantation performed at the hospital Klinikum rechts der Isar (Technische Universität München, Germany) between 2009 and 2013 were analyzed retrospectively (41 biopsies of living donors, 61 biopsies of deceased donors). Chronic allograft injury was described using the IFTA (interstitial fibrosis and tubular atrophy) or the ECAI score (extended chronic allograft injury score). The ECAI score was built out of the chronic histological lesions glomerulopathy, interstitial fibrosis, tubular atrophy and fibrous intimal thickening (cg + ci + ct + cv) of the BANFF scoring.

Intrarenal RI-values were significantly higher in patients with allograft rejection than without rejection (median 0,79 vs. 0,73; inter quartile range: 0,20 vs. 0,13; p = 0,018). The same was found for T-and non-T cell mediated rejection (median 0,78 vs. 0,73; inter quartile range 0,20 vs. 0,13; p = 0,039). There were no significant differences in the RI-values between the subtypes of T-cell mediated rejection (type IA-IIB). Furthermore, there were no significant differences of RI-values regarding antibody-mediated rejection (present vs. not present) or type of rejection (T-cell- vs. antibody mediated rejection). Patients with rejection and simultaneously chronic allograft injury showed significantly higher RI-values than patients with only chronic allograft injury. Analyses using the IFTA or the ECAI score showed comparable results (IFTA p = 0,043; Score p = 0,021). The intrarenal RI-value was neither able to detect chronic allograft injury nor to distinguish between acute tubular necrosis and rejection. The intrarenal RI-value showed a significant correlation with recipient age (p < 0,001) but not with donor features.

In summary, the intrarenal RI-value can indicate a rejection but gives no clear hint to acute tubular necrosis and cannot differentiate from it. Since patients with rejection can have normal RI-values, a biopsy should always be performed in case of suspected rejection. The intrarenal RI-value has no unambiguous validity to determine intrinsic values of the renal allograft, but should rather be understood and interpreted as a systemic parameter influenced by multiple factors.

Aim of this study was to firstly describe reproducible, objective perfusion parameters of contrast-enhanced ultrasound (CEUS) kinetics of parathyroid gland adenoma (PA) using perfusion analysis software (VueBox^®, Bracco, Italy). Thereby the efficiency of quantitative CEUS for characterization of PA should be evaluated comparing US to postoperative histopathological findings after PA resection.

42 patients with symptoms/lab work suggestive of pHPT presented a parathyroid gland lesion in B-mode US, which was consequently analyzed by dynamic CEUS. CEUS was performed by one experienced examiner after i.v.-injection of max. 2.4 ml sulphurhexaflouride microbubbles saving digital DICOM cine loops (up to 25 s) and images. PA were evaluated during arterial, venous and late phase (up to 3 min.) for perfusion characterization. A retrospective, blinded VueBox^® perfusion analysis of arterial phase of 28/42 PA was performed by a second, independent examiner placing 3 ROIs manually in the PA (center, rim of PA, surrounding thyroid gland tissue) to objectify findings. US findings were correlated to postoperative histology after PA resection.

Out of 42 patients with PA findings in CEUS, perfusion analysis could be performed in 28/42 cases only as some CEUS cine loops had too much moving. In three cases the second examiner could not detect PA retrospectively, in 25 cases PA were characterized correctly resulting in a sensitivity rate of 89.3 %. VueBox^® perfusion analysis confirmed that PA present a persisting hypervascularization of the rim with higher TTP (mean 7.93 s centrally, 8.36 s rim-sided), mTT (mean 56.6 s centrally, 64.5 s rim-sided) and lower PE (mean 10542.93 rm² centrally, 8909.21 rm² rim-sided) peripherally followed by a central wash-out during later phases. RT was comparable in all defined regions.

VueBox^® analysis of parathyroid gland CEUS examinations seemed to be a valuable tool for quantification of a PA’s perfusion and can help to detect and localize hyperfunctional parathyroid glands prior to surgery.

Prostate cancer (PCa) is one of the most common malignancies in men. The diagnostic standard to confirm prostate cancer is the transrectal ultrasound-guided biopsy. However, this procedure is associated with the underdetection of clinically significant prostate cancer and therefore needs to be improved. In the last years MRI fusion based targeted biopsy gained importance as consequence. In this study, we evaluated the quality of MRI ultrasound image fusion and evaluated factors influencing the image fusion quality. This was done by comparing fusion quality with the histopathological findings in the defined MRI target on the one hand and the PIRADS score on the other hand.

Single arm study including patients with elevated prostate specific antigen (PSA) and a multiparametric MRI showing a suspicious lesion underwent a MRI fusion targeted biopsy at our institution. MRI fusion targeted biopsy and an additional 12-core transrectal ultrasound (TRUS) guided biopsy was performed using the Philips Percunav device (Philips Medical Systems, Bothell, WA). The fusion accuracy was rated by two experienced clinicians (1 radiologist, 18 years of experience, 1 urologist, 5 years of experience) using a five-point rank scale (1 = best) and comparing the result with the histological findings in the target and the PIRADS score.

The detection rate of clinically significant cancer (Gleason 7a or greater) by MRI-ultrasound fusion targeted biopsy was 58.6% (17/29) compared to 50% (19/38) in the standard transrectal ultrasound-guided approach. PCa was found in 36.4% (4/11 patients) of patients with a PIRADS 3 lesion, in 57.7% (15/26 patients) of patients with a PIRADS 4 lesion. In 76.9% (10/13 patients) of patients with a PIRADS 5 lesion PCa was diagnosed. No statistical significance was found comparing the quality of registration either with the PIRADS (p = 0.7873) nor with the Gleason score (p = 0.4376). The study is limited by the small number of patients.

MRI fusion based targeted biopsy improves the identification of clinical significant cancer. The Gleason score of detected PCa is not influenced by the quality of fusion.

Hepatic echinococcosis (HE) is a zoonosis and depicts a rare but potentially lethal disease caused by larval infestation of E. multilocularis (alveolar echinococcosis, AE) and E. granulosus (cystic echinocococcosis, CE). In many countries, HE is a critical public health problem. Clinically, HE patients initially are often asymptomatic for years. Depending on the echinococcal manifestations patients can later develop unspecific symptoms as fatigue, abdominal pain and may present with elevated transaminases, jaundice and hepatomegaly. The combination of grey scale ultrasound and serological tests has been the gold standard for the screening and diagnosis of HE. Besides MRI, CT and FDG-PET scans, safe and directly accessible contrast-enhanced ultrasound (CEUS) may easily help to indirectly describe perilesional inflammation. Upon diagnosis of HE, an appropriate therapeutical strategy should be evaluated in a multidisciplinary way.

The aim of the present retrospective monocenter study is to assess the diagnostic performance of CEUS examination in the evaluation of hepatic echinococcal manifestation by comparison with CT, MRI, FDG-PET scans and histopathology.

Out of 36 patients with echinococcal disease (16 patients with E. multilocularis infection, 12 patients with E. granulosus infection and 8 patient with unspecified Echinococcus infection) 8 HE patients (4 patients with E. multilocularis, 2 patients with E. granulosus and 2 patients with unspecified echinococcal liver disease) were included in this study on whom CEUS was performed between 2008–2016. The applied contrast agent was a second-generation blood pool agent (SonoVue ^®, Bracco, Milan, Italy). CEUS examinations were performed and interpreted by a single experienced radiologist with more than 15 years of experience.

All patients were examined without occurrence of any side effects. In all 4 AE patients, contrast enhancement could be detected by means of CEUS and was confirmed by MRI or PET-CT scan. In the remaining 4 patients (CE and unspecified echinococcosis), doppler ultrasonography, CEUS and corresponding CT or MRI scans could not detect any hypervascularization of the lesions of interest. The histopathological analysis did not reveal any viable parasite material. CEUS showed a sensitivity of 100% and a specificity of 100% compared to MRI, CT or FDG-PET-CT.

CEUS depicts a safe method for the evaluation of echinococcal liver disease. In addition to serological tests and grey scale ultrasound, CEUS imaging could be integrated as an easily accessible tool helping to describe hypervascularization as a sonomorphological correlate for active perilesional inflammation of echinococcal manifestations. CEUS may further help to differentiate between CE and AE and also to evaluate treatment outcome.

Ultrasound is the method of choice for preoperative evaluation of masses of the parotid glands. However, existing methods do not allow for definite differentiation between the most common benign and malignant tumors.

Thus, we evaluated the benefits of Virtual Touch Quantification (VTQ) and Virtual Touch imaging quantification (VTIQ) for improving preoperative evaluation of parotid tumors.

We investigated eight lymph nodes and 41 tumors of the parotid gland via ultrasound, color Doppler ultrasound, VTIQ and VTQ shear wave imaging. Each examination consisted of pictures and videos, which were evaluated by twelve examiners. Initially, each examiner predicted whether the mass was benign or malignant based on B-mode and Doppler images. Then each examiner viewed the VTIQ and VTQ shear wave images and reevaluated the predictions, which were then compared with the histopathological outcomes.

In tumors, the sensitivity was 36% based only on B-mode and color Doppler sonography, which increased to 42% with the addition of VTIQ and VTQ. Likewise, the specificity also increased from 78% to 85%.

VTQ and VTIQ provide additional data that improve the capability to distinguish between benign and malignant tumors allowing for an increase in both the sensitivity and specificity.

Radiofrequency ablation (RFA) is an important treatment option for hepatic tumors and metastases. Post-ablation recurrence rates are reported up to 36.5 percent and seem to depend on tumor size, intrahepatic localization of tumors and adjacent hepatic vessels. Multipolar RFA has the potential to overcome/reduce these limitations. Experimental and standardized data on achievable lesion sizes, influence of hepatic vessels and non-invasive evaluation of complete ablation is still insufficient.

The aim of this study was to evaluate the influence of intrahepatic vessels on shape and size of multipolar RF-ablation zones in healthy porcine liver and to evaluate the appropriateness of immediate post-ablation contrast-enhanced computed tomography (CECT) in detecting RF-ablation dimensions.

We conducted multipolar RFAs in each of the livers of 10 healthy, narcotized and laparotomized domestic pigs by inserting three parallel probes with a constant probe distance and a constant energy supply. In 4 ablations we interrupted hepatic blood flow using Pringle’s maneuver. Immediate post-ablation CECT scans were acquired. After euthanasia the livers were sliced perpendicularly to the probes at the probes’ active centers. CECT scans were reconstructed equivalently in order to compare RF-lesion size and shape to the macroscopic sections.

In total, 19 RF-lesions were analyzed. Every RF-lesion that was ablated during physiological liver perfusion showed an irregular and cloverleaf-like shape (n = 15). Interrupting the hepatic blood flow during RFA led to well-defined, round and homogeneous ablation zones which were 3.8 times larger compared to RF-lesions ablated during continuous hepatic perfusion (n = 4). We found an excellent correlation between immediate post-ablation CECT slices and macroscopic sections when comparing RF-lesion diameters and area, although CECT tended to overestimate ablation dimensions.

The interruption of hepatic blood flow using Pringle’s maneuver during multipolar RFA with three applicators significantly reduces heat sink effects of hepatic vessels and generates large and coherent ablation zones. This approach should be considered in each case of ablation planning adjacent to larger hepatic vessels or when ablating larger tumor volumes. Immediate post-ablation CECT has limited value in detecting incomplete RFA periprocedurally.

Parabolic flights offer a unique platform for human experiments in short-term weightlessness. It is generally known that human organ systems react to changes of gravity. Yet, little is known about alterations of blood parameters under these conditions with special emphasis on blood rheology.

We investigated the alterations of distinct blood parameters after exposure to weightlessness.

14 healthy volunteers underwent short-term phases of weightlessness induced by parabolic flight. At different time points (baseline, t2:1 hour after landing, and t3:24 hours after baseline), venous blood was drawn and analyzed.

Analysis of red blood count revealed significant decreases of hemoglobin and hematocrit post flight. While total white blood counts were unaltered, differential subset analysis revealed significant decreases of eosinophil granulocytes and monocytes. Cortisole levels were unchanged and lacked physiologic circadian decrease. Parameters of renal function were found significantly improved (GFR (ml/min/1,73m²): Baseline: 105 [89;109], t2:117 [98;125], t3:110 [102;119]; p = 0.0013. In the sense of mild myocytolysis, levels of myoglobin were significantly elevated post-flight with fast recovery to baseline levels.

In the current analysis, significant alterations of blood parameters after exposure to weightlessness could be detected. These results contribute to the understanding of physiologic adaptations of the human body to weightlessness.

The oral squamous cell carcinoma (OSCC) is a leading cause of death in human malignancies. The aim of this study is to integrate the CAM Assay as a reliable and good working in vivo model for the evaluation of OSCC tumor samples and its growth into the clinical work flow.

Fresh human Tumor samples (OSCCs) 1×1 cm in size were cut into 350–450μm thick slices by a Vibratome and put on the prepared CAM model.

After growth of the tumor tissue on the CAM, we started with topical induction of proinflammatory cytokines (TNFα) and growth factors (TGFβ). After further growth of the tumor on the assay, we explanted the tumor tissue and first performed microscopic and then immunohistochemical examinations. E-cadherin and vimentin were used as Epithelial-to-mesenchymal transition (EMT) -makers and the histologic preparations were evaluated histomorphometrically. The results were correlated with clinical parameters of the patients.

Under TNFα, the small tumors (T1 / T2) show higher E-cadherin expression than larger tumors (T3 / T4). The vimentin expression under TNFα behaved in the opposite direction, at T1 / T2 the expression decreased in T3 / T4 increased. Furthermore, an increased E-cadherin expression in N0 and diminished E-cadherin expression in N1 / N2b patients could be detected depending on the N-stage of the patients. Vimentin, on the other hand, was reduced in the N0 group and expressed more frequently in the N1 / N2b group. TGFβ induction also led to increased expression of vimentin in the T3 / T4 tumors and N1 / N2b stages.

By integrating a CAM assay into the clinical workflow, tumors with preserved tumor architecture can be cultured and subjected to histological and molecular biology studies. Effects on biological behavior are recognizable and demonstrable in this model. The key markers E-cadherin and vimentin alone are not sufficient to represent the complexity of the EMT in this model. Further molecular biology and signaling pathway analyzes are necessary.

Human and equine patients are known to frequently develop vascular complications, particularly thrombosis both in veins and arteries as well as in the microvasculature.

The aim of the present study was to investigate and compare the angiogenic response of human and equine endothelial cells to lesions in an in vitro scratch assay.

Endothelial cells from human umbilical vein (HUVEC), abdominal aorta (HAAEC) and dermal microvasculature (HDMEC) as well as equine carotid artery (EACEC) and jugular vein (EVJEC) were cultured and an elongated defect was created (scratch or “wound”). Cultures were monitored over a period of 90 hours in a live cell imaging microscope.

In the human endothelial cell cultures, there was a uniform and continuous migration of the cells from the scratch fringe into the denuded area, which was closed after 17 (HUVEC), 15 (HAAEC) and 26 (HDMEC) hours. In the equine endothelial cell cultures, a complete closure of the induced defect occurred after 17 (EVJEC) and 35 (EACEC) hours.

In the equine arterial cells, the delay in closure of the denuded area seems to be the results of a disoriented and uncoordinated migration of endothelial tip cells resulting in slow re-endothelialization.

The formation of a functionally-confluent endothelial cell (EC) monolayer affords proliferation of EC, which only happens in case of appropriate migratory activity.

The migratory pathway of human umbilical endothelial cells (HUVEC) was investigated on different polymeric substrates.

Surface characterization of the polymers was performed by contact angle measurements and atomic force microscopy under wet conditions. 30,000 HUVEC per well were seeded on polytetrafluoroethylene (PTFE) (θ_adv = 119°±2°), on low-attachment plate LAP (θ_adv = 28°±2°) and on polystyrene based tissue culture plates (TCP, θ_adv = 22°±1°). HUVEC tracks (trajectories) were recorded by time lapse microscopy and the euclidean distance (straight line between starting and end point), the total distance and the velocities of HUVEC not leaving the vision field were determined.

On PTFE, 42 HUVEC were in the vision field directly after seeding. The mean length of single migration steps (SML) was 6.1±5.2 μm, the mean velocity (MV) 0.40±0.3 μm·min^-1 and the complete length of the trajectory (LT) was 710±440 μm. On TCP 82 HUVEC were in the vision field subsequent to seeding. The LT was 840±550 μm, the SML 6.1±5.2 μm and the MV 0.44±0.3 μm·min^-1. The trajectories on LAP differed significantly in respect to SML (2.4±3.9 μm, p < 0.05), the MV (0.16±0.3 μm·min^-1, p < 0.05) and the LT (410±300 μm, p < 0.05), compared to PTFE and TCP. Solely on TCP a nearly confluent EC monolayer developed after three days. While on TCP diffuse signals of vinculin were found over the whole basal cell surface organizing the binding of the cells by focal adhesions, on PTFE vinculin was merely arranged at the cell rims, and on the hydrophilic material (LAP) no focal adhesions were found.

The study revealed that the wettability of polymers affected not only the initial adherence but also the migration of EC, which is of importance for the proliferation and ultimately the endothelialization of polymer-based biomaterials.

Mesenchymal stem cells (MSCs) have been described in breast cancer models to migrate towards carcinoma and integrate into tumor associated stroma supporting tumor growth, increasing their metastatic potency and contributing to tumor-angiogenesis. Platelet-derived growth factor (PDGF) isoforms (AA, BB, CC) stimulate growth, survival and motility of MSCs and certain other cell types. Noteworthy, breast carcinomas are known to express PDGF. We aim to further shed light on i) the relevance of the different PDGF isoforms on adipose tissue derived stem cells (ASCs) migration and ii) the underlying pathway dependent on PDGF stimulation.

Breast cancer cell lines were purchased and ASC’s were isolated from murine subcutaneous adipose tissue. The transmigration of ASC’s towards the PDGF-isoforms was assessed by using recombinant human PDGF-AA, PDGF-BB and PDGF-CC in a trans-well culture dish system. Transmigrated ASC’s were quantified in 5 randomly selected fields per condition using fluorescence microscopy after calcein-staining. PDGF-BB depended transmigration of ASC’s was verified by downregulation and overexpression of PDGF-BB in breast cancer cell line using lentiviral vectors. In addition, a PI3-kinase inhibitor (LY294002) and a MAP-kinase inhibitor (PD98059) were used to identify the pathway involved in the PDGF-BB mediated migration of ASC’s towards tumor.

ASC’s transmigration significantly increased towards PDGF AA at 50 ng and only showed further increase by 500 ng which was similar to cell behavior when exposed to PDGF CC. In comparison, PDGF-BB significantly increased ASC’s transmigration already at a low level of 5 ng with further significant increase for 20 ng and 40 ng. Cell transmigration was blocked with PDGFR-α antibodies but only for PDGF-AA and PDGF-CC whereas PDGFR-β blockage showed a significant effect on transmigration for PDGF-BB and PDGF-CC but not for PDGF-AA. Neutralizing antibodies in combination with PDGF receptor blockage confirmed findings. In addition, only PI3-kinase inhibitor but not the MEK-1 selective inhibitor caused a significant decrease of transmigration for ASCs towards breast cancer cells.

The transmigration of ASC’s is most significantly enhanced by PDGF-BB via the PI3-kinase pathway. This data support that PI3-kinase is an important key player for MSC migration towards malignancy which need further research to prevent tumor progression in early disease stage.

Drug induced liver injury (DILI) is the most frequent cause for failure of new drugs in clinical studies. Thus, toxicity studies are indispensable during drug development. The proliferative human liver cell strain HepaFH3 with promising primary-like cellular properties might be a suitable liver model for such studies, but its cytochrome-P450 (CYP) expression is still in low ranges compared to freshly isolated primary human hepatocytes.

We aimed to optimize the induction protocol for CYP1A2 and CYP3A4 in HepaFH3 to obtain a physiologically relevant in vitro liver model.

CYP1A2 and CYP3A4 were induced by omeprazole and rifampicin, respectively. Induction of the two CYPs was measured by qRT-PCR, immunofluorescence and by P450 Glo enzyme activity assays.

The optimized protocol made the experimental design six days shorter than the original procedure. CYP1A2 mRNA levels were induced 118-fold, CYP3A4 levels 36-fold. This result was also reflected at protein level. Enzymatic activity of CYP1A2 increased 3.7-fold and CYP3A4 activity increased 9.8-fold after induction.

We succeeded in optimizing the induction protocol for HepaFH3 to such an extent that CYP1A2 and CYP3A4 are expressed in sufficient amounts that the cell strain can be used as a physiological relevant human liver model for in vitro toxicology studies.

The diagnostic value of Doppler ultrasonography of the portal vein for the evaluation of liver function is still contradictory.

Aim of this study was to test the relationship between clinical liver function tests based on MRI and breath testing and blood flow in the portal vein.

The portal vein velocity was measured by color coded Doppler ultrasonography (CCDS) and tested against the relative enhancement (RE), a MRI-based index of liver function. The signal intensity in the liver parenchyma was assessed before (pre) and after (post) administration of contrast agent, the RE was calculated afterwards. Further, the liver function was also assessed using a ¹³C-Methacetin-based breath test. The blood flow in the portal vein was tested for possible correlation applying Pearson’s correlation coefficient.

Using CCDS, all patients show a hepatopetal portal blood flow. The portal vein velocity is decreasing with progression of liver damage and there was a significant correlation of portal velocity with SI post (r = 0.411, p = 0.024). However, the portal velocity did not correlate significantly with the ¹³C-MBT readout (r = 0.233; p = 0.216), SI pre (r = 0.271, p = 0.147) or the relative enhancement (r = 0.303; p = 0.103).

The results of this proof-of-principle study indicate that CCDS-based assessment of portal velocity is of only limited value for the evaluation of liver function.

Contrast enhanced magnetic resonance imaging (MRI) is able to assess liver function by characteristic changes of signal intensity (SI).

The aim was to evaluate dynamic contrast-enhanced SI-indices of the abdominal aorta, portal vein and liver.

72 patients underwent Gd-EOB-DTPA-enhanced MRI and a ¹³C-methacetin-based liver breath test (¹³C-MBT) for evaluation of liver function. Region-of-interest measurements in the liver, abdominal aorta and portal vein during native, arterial (AP), late arterial (LAP), portal venous (PVP) and hepatobiliary phase (HBP) were applied to analyze SI-indices in T1-weighted volume-interpolated breath-hold examination (VIBE) sequences with fat-suppression and relative enhancement (RE) analysis was performed.

The liver (p < 0.001), the portal vein (p < 0.001) and abdominal aorta (p = 0.002) showed significant decrease of REs with decreasing liver function. An increasing trend between logarithmic values of ¹³C-MBT and REs of hepatic parenchyma (HBP; r = 0.662, p < 0.001), portal vein (PVP; r = 0.532, p < 0.001) and abdominal aorta (PVP; r = 0.421, p < 0.001) was observed.

RE measurements of the hepatic parenchyma proofed to be a trustable evaluation method for liver function evaluation. In accordance with liver function, changes of REs in the portal vein and abdominal aorta occur.