Martin E Eichhorn

Goethe-Universität Frankfurt am Main, Frankfurt am Main, Hesse, Germany

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Publications (56)181.19 Total impact

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    ABSTRACT: Contrast enhanced ultrasound (CE-US) is a promising imaging modality for non-invasive analysis of functional vascularisation. Lesions of the parotid gland are associated with a vascularisation that differs from normal gland tissue. The aim of this clinical study was to further analyse the perfusion in parotid gland lesions with CE-US. The new quantification software VueBox (Bracco, Italy) was used to assess the perfusion, based on DICOM datasets of CE-US examination.
    Clinical hemorheology and microcirculation 01/2014; 58(1):261-9. · 3.40 Impact Factor
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    ABSTRACT: Contrast enhanced ultrasound (CE-US) is a promising imaging modality for non-invasive analysis of parotid gland lesions because their vascularisation differs from normal gland tissue. This clinical study should further investigate CE-US as a diagnostic tool for parotid gland tumors. 39 patients underwent CE-US measurements after intravenous application of a contrast agent (SonoVue, Bracco, Italy) before surgical tumor resection. Time-intensity curves gradients were calculated and parameters of intratumoral microcirculation were analysed. The vascularisation parameters were compared among the different tumor entities as defined per definitive histological diagnosis. Histological analyses revealed 17 pleomorphic adenoma, 15 cystadenolymphoma and 7 malignoma. A significant difference of area below intensity time curve (AUC) and mean transit time (MTT) was measured in the malignant lesions compared to benign tumors (p<0.05). A significant difference of AUC and maximum of signal increase (ΔSImax) for pleomorphic adenoma versus cystadenolymphoma was found (p<0.05). CE-US seems to be a quantitative and independent method for the assessment of malign and benign parotid gland tumors. Further studies and clinical experience will have to validate this method as a reliable diagnostic tool that facilitates preoperative planning.
    European journal of radiology 08/2013; · 2.65 Impact Factor
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    ABSTRACT: The aim of this first-time-in-human non-randomized dose-escalating prospective phase I clinical trial was to analyze safety of two doses of fluorescent rhodamine-labeled cationic liposomes (LDF01) in head and neck squamous cell carcinoma (HNSCC). Patients had resectable UICC stadium I-IV A HNSCCs. LDF01 was administered before tumor resection under general anesthesia as an intravenous infusion with effective lipid doses of 0.5 or 2 mg/kg b.w., respectively. In addition to clinical monitoring for safety assessment, tumor biopsies were taken during the surgical procedure for fluorescence histological analysis. Eight patients were assigned to the two dose groups. During safety follow-up no clinically relevant adverse events occurred. Fluorescence histology revealed some evidence of favorable selectivity of LDF01 for tumor microvessels in the high-dose group. LDF01 is safe applied as infusion at both tested dose levels. Furthermore, LDF01 can be detected in the vicinity of tumor cells and could be assigned to the microvessel target in individual HNSSC cases. Detailed analysis of targeting properties of LDF01 has to be performed in upcoming clinical phase II trials.
    Archives of Oto-Rhino-Laryngology 09/2012; · 1.29 Impact Factor
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    ABSTRACT: After pancreas transplantation (PTx), early capillary malperfusion and leukocyte recruitment indicate the manifestation of severe ischemia/reperfusion injury (IRI). Oscillatory blood-flow redistribution (intermittent capillary perfusion, IP), leading to an overall decrease in erythrocyte flux, precedes complete microvascular perfusion failure with persistent blood flow cessation. We addressed the role of intercellular adhesion molecule-1 (ICAM-1) for leukocyte-endothelial interactions (LEIs) after PTx and evaluated the contribution of IP and malperfusion. Pancreas transplantation was performed in rats after 18-hour preservation, receiving either isotype-matched IgG or monoclonal anti-ICAM-1 antibodies (10 mg/kg intravenously) once before reperfusion. Leukocyte-endothelial interaction, IP, erythrocyte flux, and functional capillary density, respectively, were examined in vivo during 2-hour reperfusion. Nontransplanted animals served as controls. Tissue samples were analyzed by histomorphometry. In grafts of IgG-treated animals, IP was encountered already at an early stage after reperfusion and steadily increased over 2 hours, whereas erythrocyte flux declined continuously. In contrast, inhibition of ICAM-1 significantly improved erythrocyte flux and delayed IP appearance by 2 hours. Further, anti-ICAM-1 significantly reduced LEI and leukocyte tissue infiltration when compared to IgG; edema development was less pronounced in response to anti-ICAM-1 monoclonal antibody. Intercellular adhesion molecule-1 blockade significantly attenuates IRI via immediate reduction of LEI and concomitant improvement of capillary perfusion patterns, emphasizing its central role during IRI in PTx.
    Pancreas 05/2012; 41(7):1112-8. · 2.95 Impact Factor
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    ABSTRACT: Angiogenesis, the formation of new blood vessels from the endothelium of the existing vasculature, describes a crucial process in tumor growth, disease progression, and metastasis. Therefore, the upcoming strategy of inhibiting tumor angiogenesis has generated different treatment modalities, which have been transferred into clinical practice in recent years. Currently, this concept is applied to target the vasculature of different visceral tumors and intensive clinical research has just started. This review summarizes the modifications of systemic treatment of visceral tumors by targeting the vasculature in the past years. Moreover, novel targets and treatment strategies will be discussed to evaluate future directions. Leading antiangiogenic drugs combined with systemic chemotherapy have been applied with increasing success during the last years. Therefore, the concept of combining vascular targeting agents with established chemotherapeutic regimens has been increasingly adopted into the therapies of different visceral tumors. Targeting the vasculature of visceral tumors in combination with established standard tumor therapies includes major clinical potential for future therapy concepts.
    Langenbeck s Archives of Surgery 03/2012; 397(4):569-78. · 1.89 Impact Factor
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    ABSTRACT: The standard treatment of poisoning by organophosphorus (OP) nerve agents with atropine and oximes is not sufficiently effective against all types of nerve agents. Alternative therapeutic strategies are required and bispyridinium non-oximes, acting as nicotinic antagonists, were identified as promising compounds. A previous study showed that the di(methanesulfonate) salt of the bispyridinium compound MB327 could restore soman-impaired neuromuscular function in vitro and improve survival of sarin, soman and tabun poisoned guinea pigs in vivo. Here, by using the indirect field stimulation technique, the ability of MB327 to counteract soman-impaired neuromuscular transmission was investigated in human intercostal muscle and rat diaphragm preparations. MB327 restored muscle force in a concentration-dependent manner in both species without reactivating soman-inhibited acetylcholinesterase. The therapeutic effect of MB327 could be washed out, indicating a direct effect at the nicotinic receptor level. Also the ability of MB327 to restore respiratory muscle function could be demonstrated for the first time in rat and human tissue. In combination with previous in vitro and in vivo findings MB327 may be considered a promising compound for the treatment of nerve agent poisoning and further studies are needed to identify optimized drug combinations, concentrations and dosing intervals to provide an effective therapy for OP poisoning.
    Toxicology 02/2012; 294(2-3):80-4. · 4.02 Impact Factor
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    ABSTRACT: Donor organ shortage represents a major problem in lung transplantation. Donation after cardiac death could help to expand the pool of organs, but the additional period of warm ischemia after cardiac arrest aggravates primary graft dysfunction. The pulmonary endothelium of the graft constitutes an important source and target of reactive oxygen species generated during ischemia and reperfusion. Targeted protection of graft pulmonary endothelial cells by the antioxidant enzyme catalase, conjugated with a platelet/endothelial cell adhesion molecule-1 (PECAM-1) antibody to nanosized particles (anti-PECAM/catalase conjugates), might improve outcome in lung transplantation using donors after cardiac death and prolonged hypothermic preservation. Left lung transplantation was performed in 18 pigs. Before cardiac arrest, donors received anti-PECAM/catalase, unconjugated component mixture or vehicle solution. After 90-min warm and 18-hr hypothermic ischemia, lungs were transplanted, and function was assessed during 6 hr after reperfusion. Samples of bronchoalveolar lavage fluid and lung tissue were taken thereafter. Six sham-operated animals served as controls. During 6-hr reperfusion, anti-PECAM/catalase significantly ameliorated graft function, evidenced by major improvements of gas exchange and reduced intrapulmonary shunt fraction. Furthermore, lipid peroxidation, alveolar leakage, and edema formation were reduced in protected grafts. Similarly moderate lung pathology was seen after transplantation. Augmentation of the antioxidant capacity of graft pulmonary endothelial cells with anti-PECAM/catalase nanoparticles represents a straightforward approach to enable a safe transplantation of prolonged preserved donation after cardiac death lungs. Anti-PECAM/catalase protection alleviated oxidative stress and allowed immediate reconstitution of normal gas exchange and pulmonary microcirculation, a prerequisite for improved graft and patient outcome.
    Transplantation 08/2011; 92(4):380-7. · 3.78 Impact Factor
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    ABSTRACT: In the past the detection of tumor perfusion was achieved solely via invasive procedures, such as intravital microscopy or with the help of costly modalities, such as multidetector computed tomography (MDCT), magnetic resonance tomography (MRT) or the combined use of positron emission tomography and computed tomography (PET/CT). Ultrasound offers the non-invasive display of organs without usage of ionizing radiation and it is widely available. However, colour-coded ultrasound and power Doppler do not allow the detection of tumor microcirculation. The introduction of contrast-enhanced ultrasound (CEUS) as well as new high-frequency ultrasound probes made it possible to detect and quantify tumor microcirculation with high resolution. CEUS has been used clinically on human beings for more than 10 years. During the last years different tumor models in experimental animals were used for the establishment of this new technique, e.g. in rats, hamsters and mice. CEUS allows the detection of functional parameters, such as the angiogenetic metabolic status of tissue pretreatment and posttreatment. Further research is required to solve the problems of absolute quantification of these perfusion parameters to allow the comparison of CEUS with other modalities (e.g. MRT and CT).
    Der Radiologe 06/2011; 51(6):506-13. · 0.47 Impact Factor
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    ABSTRACT: In spite of the development and widespread avail-ability of modern antibiotics, pleural empyema still represents a serious intrathoracic disease -associated with significant morbidity and mortality. Patients with complicated parapneumonic effusions and empyema have an increased morbidity and mortality due at least in part to inappropriate and delayed management of pleural space infections. Timely diagnosis of pleural empyema and rapid initiation of the appropriate surgical treatment modality represent keystone principles for efficient treatment of thoracic -empyema. Simple drainage, minimally invasive surgical treatment modalities (VATS) and image-guided small-bore catheters in combination with adjunctive fibrinolytic drugs have extended the potential therapeutic arsenal. Individual case management with a flexible selection of the most appropriate treatment modality by experienced thoracic surgeons may lead to improved outcomes. In this context a summary of the most recent opinions and results in thoracic empyema management is outlined in the present review.
    Zentralblatt für Chirurgie 02/2011; 136(1):34-41. · 0.69 Impact Factor
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    ABSTRACT: In der Vergangenheit war die Darstellung der Tumorperfusion ausschließlich mit Hilfe invasiver Verfahren wie etwa der intravitalen Mikroskopie oder aber apparativ aufwendiger Großgeräte wie z.B. bei der Multidetektorcomputertomographie (MDCT), der Magnetresonanztomographie (MRT) oder dem gemeinsamen Einsatz der Positronenemissionstomographie und der Computertomographie (PET/CT) möglich. Ein Vorteil der Sonographie ist die nichtinvasive Darstellung des Körperinneren mit einer hohen räumlichen und zeitlichen Auflösung ohne Anwendung ionisierender Strahlung. Durch die Anwendung der farbkodierten Duplexsonographie (FKDS) sowie des Powerdopplers lässt sich jedoch keine Tumorvaskularität detektieren. Die Einführung des kontrastverstärkten Ultraschalls („contrast-enhanced ultrasound“, CEUS) sowie die Entwicklung neuer hochfrequenter Ultraschallköpfe ermöglichen es, die Mikrozirkulation in Tumoren zeitlich hochaufgelöst zu detektieren und zu quantifizieren. Der CEUS wird in der Klinik bereits seit über 10Jahren am Menschen eingesetzt. In letzter Zeit wird er auch für tierexperimentelle Untersuchungen, z.B. bei Tumormodellen an Mäusen, Hamstern oder Ratten genutzt. Durch die Analyse der individuellen Kontrastmittelkinetik vor und nach Therapie können funktionelle Informationen über den angiogenetisch-metabolischen Status des Gewebes gewonnen werden. Weitere Forschungsprojekte sind nötig, um eine absolute Quantifizierung der Perfusionsparameter zu erreichen und die wünschenswerte Vergleichbarkeit mit anderen Untersuchungsmodalitäten (MRT, CT) herstellen zu können. In the past the detection of tumor perfusion was achieved solely via invasive procedures, such as intravital microscopy or with the help of costly modalities, such as multidetector computed tomography (MDCT), magnetic resonance tomography (MRT) or the combined use of positron emission tomography and computed tomography (PET/CT). Ultrasound offers the non-invasive display of organs without usage of ionizing radiation and it is widely available. However, colour-coded ultrasound and power Doppler do not allow the detection of tumor microcirculation. The introduction of contrast-enhanced ultrasound (CEUS) as well as new high-frequency ultrasound probes made it possible to detect and quantify tumor microcirculation with high resolution. CEUS has been used clinically on human beings for more than 10 years. During the last years different tumor models in experimental animals were used for the establishment of this new technique, e.g. in rats, hamsters and mice. CEUS allows the detection of functional parameters, such as the angiogenetic metabolic status of tissue pretreatment and posttreatment. Further research is required to solve the problems of absolute quantification of these perfusion parameters to allow the comparison of CEUS with other modalities (e.g. MRT and CT). SchlüsselwörterKontrastverstärkter Ultraschall–Tumorresponse–Wiederauffüllungskinetik–Kontrastmittelquantifizierung–Tierexperimentell KeywordsContrast-enhanced ultrasound (CEUS)–Tumor response–Flash replenishment method–Absolute quantification–Animal experiments
    Der Radiologe 01/2011; 51(6):506-513. · 0.47 Impact Factor
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    ABSTRACT: Cancer stem cells (CSCs) or tumor initiating cells were identified and characterized as a unique subpopulation with stem cell features in many types of cancer. Current CSC studies provide novel insights regarding tumor initiation, progression, angiogenesis, resistance to therapy and interplay with the tumor micro-environment. A cancer stem cell niche has been proposed based on these findings. The niche provides the soil for CSC self-renewal and maintenance, stimulating essential signaling pathways in CSCs and leading to secretion of factors that promote angiogenesis and long term growth of CSCs. We present evidence which has emerged over the past 5 years indicating interaction of CSCs with angiogenesis in the proposed "vascular niche". Based on these findings, targeting the "cancer stem cell niche" by combining an individualized anti-CSC approach with treatment of their microenvironment may represent a novel therapeutic strategy against solid tumor systems.
    The International journal of developmental biology 01/2011; 55(4-5):477-82. · 2.16 Impact Factor
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    ABSTRACT: Anastomotic leakage after esophagectomy is an important determinant of early and late morbidity and mortality. Control of the septic focus is essential when treating patients with anastomotic leakages. Surgical and endoscopic treatment options are limited. Between 2005 and 2009, we treated 6 patients who experienced an intrathoracic anastomotic leakage after esophageal resection. After all established therapeutic measures had failed, we explored the feasibility of an endoscopically assisted mediastinal vacuum therapy. We were able to heal intrathoracic esophageal leakages in all 6 patients without any local complications and without the need for reoperation. One patient died because of a progressive pneumonia. Endoscopic vacuum-assisted closure of anastomotic leakages may help to overcome the limitations that are associated with intermittent endoscopic treatment and conventional drainage therapy. Our preliminary results suggest that this new concept may be suitable for those patients.
    The Annals of thoracic surgery 11/2010; 90(5):1674-81. · 3.45 Impact Factor
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    ABSTRACT: The increasing interest in biomedical applications of semiconductor quantum dots (QDs) is closely linked to the use of surface modifications to target specific sites of the body. The immense surface area of vascular endothelium is a possible interaction platform with systemically administered QDs. Therefore, the aim of this study was to investigate the microvascular distribution of neutral, cationic, and anionic QDs in vivo. QDs with carboxyl-, amine- and polyethylene glycol surface coatings were injected into the blood circulation of mice. In vivo microscopy of the cremaster muscle, two-photon microscopy of skeletal and heart muscle, as well as quantitative fluorescence measurements of blood, excreta, and tissue samples were performed. Transmission electron microscopy was used to detect QDs at the cellular level. The in vitro association of QDs with cultured endothelial cells was investigated by flow cytometry and confocal microscopy. Anionic QDs exhibited a very low residence time in the blood stream, preferably accumulated in organs with a prominent mononuclear phagocytic component, but were also found in other tissues with low phagocytic properties where they were predominantly associated with capillary endothelium. This deposition behavior was identified as a new, phagocyte-independent principle contributing to the rapid clearance of anionic QDs from the circulation.
    Biomaterials 09/2010; 31(26):6692-700. · 8.31 Impact Factor
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    ABSTRACT: Quantitative analysis of tumour angiogenesis is an indispensable prerequisite for the development of novel antivascular treatment strategies. The aim of this study was to develop an automated analysis technique enabling quantitative assessment of complete tumour vascular networks non-invasively in vivo. Experiments were performed in A-Mel-3 implanted in transparent dorsal skinfold chambers of the Syrian Golden hamster. Tumours were imaged in two dimensions by means of a computer controlled scanning-table combined with intravital microscopy. Functional vessel density was automatically quantified online with a digital imaging application package. Data for functional vessel density correlated excellently with data obtained by off-line video-based frame-by-frame analysis (R((S))=0.947, r(2)=0.959, n=48). This new technique enables automated, quantitative assessment of complete tumour vascular networks and therefore provides a promising tool to characterise changes of the entire tumour vascularity in response to antivascular treatment regimes.
    Anticancer research 07/2010; 30(7):2597-602. · 1.71 Impact Factor
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    ABSTRACT: The aim of the study was to quantitatively assess tumor microcirculation upon vascular targeting tumor therapy by non-destructive contrast enhanced ultrasonography (CEUS) and to validate this technology by correlation with high-resolution intravital fluorescence microscopy (IVM). Subcutaneous Lewis Lung carcinomas (LLC-1) carcinomas were established in mice. A-MEL-3 melanomas were grown in dorsal skinfold chambers of hamsters to permit bimodal imaging of tumor microcirculation by CEUS and IVM. Animals were treated by i.p. injection of ZD6126 and CEUS imaging after bolus injection of microbubbles was performed. Red blood cell velocity (VRBC), segmental blood flow (Q) and microcirculatory perfusion (PI) of tumors was quantified by IVM. Change in signal intensity (SI) from baseline (ΔSI), rate of SI increase (RSI) and area below intensity time curves (AUC) were calculated in tumors by analysis of CEUS data. Microvessel density was measured by quantitative analysis of CD31 immunohistochemistry. The Mann-Whitney test was used to evaluate differences between groups. Spearman correlation test was used to investigate the relation between CEUS and IVM parameters or histologic CD31 count. ΔSI, RSI and AUC values in ZD6126 treated tumors were lower compared to untreated controls. Comparing central and peripheral tumor regions a vascularized viable rim in the tumor periphery could be detected by CEUS imaging. For the entire cohort ΔSI, RSI and AUC values positively correlated with VRBC, Q and PI quantified by IVM. In LLC-1 carcinomas a positive correlation between ΔSI, RSI and AUC and histological assessment of tumor vascularity was found. In conclusion tumor vascular response to vascular targeting therapy can be quantified non-invasively by CEUS. Bimodal tumor imaging by intravital microscopy and CEUS represents an experimental tool to further develop molecular imaging of tumor microcirculation by CEUS.
    Cancer biology & therapy 05/2010; 9(10):794-802. · 3.29 Impact Factor
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    ABSTRACT: The close association of lymphatic and blood vessels and their coordinated development in vivo suggest that there are parallel mechanisms regulating hemangiogenesis and lymphangiogenesis. Here, we hypothesize that inhibition of the Src tyrosine kinase, apart from anti-hemangiogenic effects, results in a suppression of lymphangiogenesis. The ability of the Src kinase inhibitor PP2 to block Src in isolated lymphatic endothelial cells (LECs) was analyzed by Western Blot. The effects of PP2 on LEC proliferation, migration, and sprouting were assessed by MTT, Boyden chamber, and spheroid assays, respectively. The level of VEGF-C secreted by L3.6pl pancreatic carcinoma cells was measured by ELISA. For in vivo assessment of lymphangiogenesis, Src kinase inhibitor AZM475271 was used in mouse corneal micropocket and lymphangioma models. VEGF-C stimulation of isolated LECs led to an increased phosphorylation of Src kinase that was abrogated by PP2. Treatment with PP2 inhibited spheroid sprouting of LECs at even lower concentrations than suggested by the proliferation assay. Src inhibition significantly reduced the level of VEGF-C in L3.6pl supernatant. Treatment with PP2 also resulted in a significant reduction in the migratory activity of LECs. In vivo, Src inhibition reduced de novo formation of lymphangiomas and corneal neovascularization. Inhibition of Src kinase shows strong anti-lymphangiogenic activity in vitro and in vivo. Together with anti-angiogenic effects mediated by Src inhibition, this strategy may be attractive in the treatment of lymphatic and hematogeneous metastasis of cancer.
    Current cancer drug targets 04/2010; 10(5):546-53. · 5.13 Impact Factor
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    ABSTRACT: Pancreatic fistula (PF) represents a major complication after distal pancreatectomy. In a consecutive series of 110 patients, risk factors for the incidence of PF and surgical morbidity were identified. Patients having undergone distal pancreatectomy between 2003 and 2007 were identified. Clinicopathologic parameters as well as perioperative data were correlated with the incidence of PF and overall surgical morbidity using univariate and multivariate models. In 72 patients (65%), malignant disease was present. Splenectomy and multivisceral resection were performed in 84 (76%) and 47 (42%) patients, respectively. Overall major surgical morbidity was 18%, and 12 patients (11%) developed PFs. A body mass index > 25 kg/m(2) was the only independent significant predictive factor for PF. Malignancy, splenectomy, multivisceral resection, transfusion, comorbidity, and stapler use did not show statistical significance. For overall surgical morbidity, there was no significant indicator. A body mass index > 25 kg/m(2) contributes to the incidence of PF after distal pancreatectomy. Other parameters did not show a significant influence on PF or on overall surgical morbidity.
    American journal of surgery 04/2010; 200(3):311-7. · 2.36 Impact Factor
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    ABSTRACT: Ischemia/reperfusion (I/R) injury plays a pivotal role in the development of graft pancreatitis, with ischemia time representing one of its crucial factors. However, it is unclear, whether exocrine and endocrine tissue experience similar inflammatory responses during pancreas transplantation (PTx). This study evaluated inflammatory susceptibilities of islets of Langerhans (ILH) and exocrine tissue after different preservation periods during early reperfusion. PTx was performed in rats following 2 h (2h-I) or 18 h (18h-I) preservation. Leukocyte-endothelial cell interactions (LEI) were analyzed in venules of acinar tissue and ILH in vivo over 2 h reperfusion. Nontransplanted animals served as controls. Tissue samples were analyzed by histomorphometry. In exocrine venules leukocyte rolling predominated in the 2h-I group. In the 18h-I group, additionally, high numbers of adherent leukocytes were found. Histology revealed significant edema formation and leukocyte extravasation in the 18h-I group. Notably, LEI in postcapillary venules of ILH were significantly lower. Leukocyte rolling was only moderately enhanced and few leukocytes were found adherent. Histology revealed minor leukocyte extravasation. Ischemia time contributes decisively to the extent of the I/R-injury in PTx. However, ILH have a significantly lower susceptibility towards I/R, even when inflammatory reactions in adjacent exocrine tissue are evident.
    European Surgical Research 01/2010; 44(3-4):192-200. · 0.75 Impact Factor
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    ABSTRACT: Solide Tumoren entstehen durch die Anhäufung von genetischen Mutationen oder Verlusten bestimmter Allele in Körper- oder Keimzellen und den dadurch bedingten Ausfall zellinterner Kontrollmechanismen mit konsekutiv ungehemmtem Zellwachstum. Dieser Umstand ist unter anderem in der Adenom-Karzinom-Sequenz von kolorektalen Karzinomen beschrieben und stellt sich meist als schrittweiser Prozess ausgehend von der mutierten Zelle über einen nichtinvasiven Tumor bis hin zum invasiven, metastasierenden Karzinom dar (Hanahan u. Weinberg 2000). Die verschiedenen genetischen Veränderungen bewirken einen Überlebens- und Wachstumsvorteil der mutierten Zellen und begünstigen die Entstehung von Tumoren mikroskopischer und im weiteren Verlauf auch makroskopischer Größe. Um den Prozess des Tumorwachstums und dem Zuwachs seiner Malignität zu verstehen, muss neben den genetischen Veränderungen in der Tumorzelle auch die Interaktion des Tumors mit dem umliegenden Mikromilieu, insbesondere mit dem Gefäßssystem betrachtet werden.
    12/2009: pages 77-86;
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    ABSTRACT: Exposure to static magnetic fields (SMFs) results in a reduced blood flow in tumor vessels as well as in activation and adherence of platelets. Whether this phenomenon may have a significant functional impact on tumors has not been investigated as yet. The aim of our study was to evaluate the effects of prolonged exposure to SMFs on tumor angiogenesis and growth. Experiments were performed in dorsal skinfold chamber preparations of Syrian Golden hamsters bearing syngenic A-Mel-3 melanomas. On 3 d following tumor cell implantation one group of animals was immobilized and exposed to a SMF of 586 mT for three h. Control animals were immobilized for the same duration without SMF exposure. Using in vivo-fluorescence microscopy the field effects on tumor angiogenesis and microcirculation were analyzed for seven days. Tumor growth was assessed by repeated planimetry of the tumor area during the observation period. Exposure to SMFs resulted in a significant retardation of tumor growth ( approximately 30%). Furthermore, histological analysis showed an increased peri- and intratumoral edema in tumors exposed to SMFs. Analysis of microcirculatory parameters revealed a significant reduction of functional vessel density, vessel diameters and red blood cell velocity in tumors after exposure to SMFs compared to control tumors. These changes reflect retarded vessel maturation by antiangiogenesis. The increased edema after SMF exposure indicates an increased tumor microvessel leakiness possibly enhancing drug-uptake. Hence, SMF therapy appears as a promising new anticancer strategy-as an inhibitor of tumor growth and angiogenesis and as a potential sensitizer to chemotherapy.
    Cancer biology & therapy 10/2009; 8(18):1756-62. · 3.29 Impact Factor

Publication Stats

771 Citations
181.19 Total Impact Points

Institutions

  • 2012
    • Goethe-Universität Frankfurt am Main
      • Klinik für Hals-, Nasen-, Ohrenheilkunde
      Frankfurt am Main, Hesse, Germany
  • 2002–2012
    • Ludwig-Maximilian-University of Munich
      • • Department of Surgery
      • • Department of Internal Medicine II
      • • Department of Ear, Nose and Throat Medicine
      München, Bavaria, Germany
  • 2009
    • University Hospital München
      München, Bavaria, Germany