106 research outputs found

    A new type of reconstruction on the InSb() surface determined by grazing incidence X-ray diffraction

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    The (3Ă—3) reconstruction of the InSb( ) surface has been investigated by grazing incidence X-ray diffraction and scanning tunneling microscopy. The structure is characterized by 6-atom rings on top of a slightly buckled InSb top double layer. Two types of rings have been found, an elliptic ring consisting of 4 In and 2 Sb atoms and a trigonal ring with 3 In and 3 Sb atoms. The bond angles and lengths are consistent with the concept of rehybridization and depolarization which explains the reconstructions of the (111) and (110) surfaces

    Interventionally implanted port catheter systems for hepatic arterial infusion of chemotherapy in patients with primary liver cancer: a phase II-study (NCT00356161)

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    BACKGROUND: Hepatic arterial infusion (HAI) of chemotherapy requires the implantation of a transcatheter application system which is traditionally performed by surgery. This procedure, but particularly the adjacent drug application via pump or port is often hampered by specific complications and device failure. Interventionally implanted port catheter systems (IIPCS) facilitate the commencement of HAI without need for laparatomy, and are associated with favorable complication rates. We here present an evaluation of the most important technical endpoints associated with the use of IIPCS for HAI in patients with primary liver cancers. METHODS: 70 patients (pts) with hepatocellular (HCC, n=33) and biliary tract cancer (BTC, n=37) were enrolled into a phase II -study. Of those, n=43 had recurrent disease and n=31 suffered from liver-predominant UICC-stage IVb. All pts were provided with IIPCSs before being treated with biweekly, intraarterial chemotherapy (oxaliplatin, 5-Flourouracil, folinic acid). The primary objective of the trial was defined as evaluation of device-related complications and port duration. RESULTS: Implantation of port catheters was successful in all patients. Mean treatment duration was 5,8 months, and median duration of port patency was not reached. Disease-progression was the most common reason for treatment discontinuation (44 pts., 63%), followed by chemotherapy-related toxicity (12 pts., 17%), and irreversible device failure (5 pts., 7%). A total of 28 port complications occurred in 21 pts (30%). No unexpected complications were observed. CONCLUSIONS: HAI via interventionally implanted port catheters can be safely applied to patients with primary liver tumors far advanced or/and pretreated

    Visualizing landscapes of the superconducting gap in heterogeneous superconductor thin films: geometric influences on proximity effects

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    The proximity effect is a central feature of superconducting junctions as it underlies many important applications in devices and can be exploited in the design of new systems with novel quantum functionality. Recently, exotic proximity effects have been observed in various systems, such as superconductor-metallic nanowires and graphene-superconductor structures. However, it is still not clear how superconducting order propagates spatially in a heterogeneous superconductor system. Here we report intriguing influences of junction geometry on the proximity effect for a 2D heterogeneous superconductor system comprised of 2D superconducting islands on top of a surface metal. Depending on the local geometry, the superconducting gap induced in the surface metal region can either be confined to the boundary of the superconductor, in which the gap decays within a short distance (~ 15 nm), or can be observed nearly uniformly over a distance of many coherence lengths due to non-local proximity effects.Comment: 17 pages, 4 figure

    A lattice gas model of II-VI(001) semiconductor surfaces

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    We introduce an anisotropic two-dimensional lattice gas model of metal terminated II-IV(001) seminconductor surfaces. Important properties of this class of materials are represented by effective NN and NNN interactions, which result in the competition of two vacancy structures on the surface. We demonstrate that the experimentally observed c(2x2)-(2x1) transition of the CdTe(001) surface can be understood as a phase transition in thermal equilbrium. The model is studied by means of transfer matrix and Monte Carlo techniques. The analysis shows that the small energy difference of the competing reconstructions determines to a large extent the nature of the different phases. Possible implications for further experimental research are discussed.Comment: 7 pages, 2 figure

    Relationship between pp65 antigenemia levels and real-time quantitative DNA PCR for Human Cytomegalovirus (HCMV) management in immunocompromised patients

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    <p>Abstract</p> <p>Background</p> <p>Quantitative real-time PCR assays, which are more rapid and practical than pp65 antigenemia determination, are progressively becoming the preferred method for monitoring Human Cytomegalovirus (HCMV) reactivation. However, the relationship between HCMV DNA and antigenemia levels is still under investigation. The aim of this study was to analyse the relationship between HCMV DNA and pp65 antigenemia levels in order to identify clinically useful threshold values for the management of patients.</p> <p>Methods</p> <p>475 consecutive samples from 156 immunosuppressed patients were tested for HCMV by pp65 antigenemia and Real-time PCR assay.</p> <p>Results </p> <p>136 out of 475 consecutive samples derived from 48 patients showed evidence of HCMV infection. HCMV DNA was detected in 106 samples, pp65 antigen in 3, and both markers in 27. pp65 antigen detection was associated with higher HCMV DNA levels. The cut-off HCMV DNA level that best predicted pp65 antigenemia in this series of samples was 11,500 copies/ml, but different threshold levels could be observed for specific groups of patients. HCMV disease was observed in 5 out of 48 patients with active HCMV infection. The presence of clinical symptoms was associated with positive pp65 and with higher antigenemia levels. Higher HCMV DNA load at the onset of viral replication was correlated to the development of clinical symptoms.</p> <p>Conclusion</p> <p>Both pp65 antigenemia and HCMV DNA load can be useful for the prospective monitoring of immunocompromised subjects. Specific cut-off levels capable of triggering preemptive antiviral treatment should be determined in accordance to the type of test used and the characteristics of patients and prospectively validated.</p

    LICC: L-BLP25 in patients with colorectal carcinoma after curative resection of hepatic metastases--a randomized, placebo-controlled, multicenter, multinational, double-blinded phase II trial

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    Background: 15-20% of all patients initially diagnosed with colorectal cancer develop metastatic disease and surgical resection remains the only potentially curative treatment available. Current 5-year survival following R0-resection of liver metastases is 28-39%, but recurrence eventually occurs in up to 70%. To date, adjuvant chemotherapy has not improved clinical outcomes significantly. The primary objective of the ongoing LICC trial (L-BLP25 In Colorectal Cancer) is to determine whether L-BLP25, an active cancer immunotherapy, extends recurrence-free survival (RFS) time over placebo in colorectal cancer patients following R0/R1 resection of hepatic metastases. L-BLP25 targets MUC1 glycoprotein, which is highly expressed in hepatic metastases from colorectal cancer. In a phase IIB trial, L-BLP25 has shown acceptable tolerability and a trend towards longer survival in patients with stage IIIB locoregional NSCLC. Methods: This is a multinational, phase II, multicenter, randomized, double-blind, placebo-controlled trial with a sample size of 159 patients from 20 centers in 3 countries. Patients with stage IV colorectal adenocarcinoma limited to liver metastases are included. Following curative-intent complete resection of the primary tumor and of all synchronous/metachronous metastases, eligible patients are randomized 2:1 to receive either L-BLP25 or placebo. Those allocated to L-BLP25 receive a single dose of 300 mg/m2 cyclophosphamide (CP) 3 days before first L-BLP25 dose, then primary treatment with s.c. L-BLP25 930 mug once weekly for 8 weeks, followed by s.c. L-BLP25 930 mug maintenance doses at 6-week (years 1&2) and 12-week (year 3) intervals unless recurrence occurs. In the control arm, CP is replaced by saline solution and L-BLP25 by placebo. Primary endpoint is the comparison of recurrence-free survival (RFS) time between groups. Secondary endpoints are overall survival (OS) time, safety, tolerability, RFS/OS in MUC-1 positive cancers. Exploratory immune response analyses are planned. The primary endpoint will be assessed in Q3 2016. Follow-up will end Q3 2017. Interim analyses are not planned. Discussion: The design and implementation of such a vaccination study in colorectal cancer is feasible. The study will provide recurrence-free and overall survival rates of groups in an unbiased fashion. Trial Registration EudraCT Number 2011-000218-2

    A hepatoprotective Lindera obtusiloba extract suppresses growth and attenuates insulin like growth factor-1 receptor signaling and NF-kappaB activity in human liver cancer cell lines

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    <p>Abstract</p> <p>Background</p> <p>In traditional Chinese and Korean medicine, an aqueous extract derived from wood and bark of the Japanese spice bush <it>Lindera obtusiloba </it>(<it>L.obtusiloba</it>) is applied to treat inflammations and chronic liver diseases including hepatocellular carcinoma. We previously demonstrated anti-fibrotic effects of <it>L.obtusiloba </it>extract in hepatic stellate cells. Thus, we here consequently examine anti-neoplastic effects of <it>L.obtusiloba </it>extract on human hepatocellular carcinoma (HCC) cell lines and the signaling pathways involved.</p> <p>Methods</p> <p>Four human HCC cell lines representing diverse stages of differentiation were treated with <it>L.obtusiloba </it>extract, standardized according to its known suppressive effects on proliferation and TGF-β-expression. Beside measurement of proliferation, invasion and apoptosis, effects on signal transduction and NF-κB-activity were determined.</p> <p>Results</p> <p><it>L.obtusiloba </it>extract inhibited proliferation and induced apoptosis in all HCC cell lines and provoked a reduced basal and IGF-1-induced activation of the IGF-1R signaling cascade and a reduced transcriptional NF-κB-activity, particularly in the poorly differentiated SK-Hep1 cells. Pointing to anti-angiogenic effects, <it>L.obtusiloba </it>extract attenuated the basal and IGF-1-induced expression of hypoxia inducible factor-1α, vascular endothelial growth factor, peroxisome proliferator-activated receptor-γ, cyclooxygenase-2 and inducible nitric oxide synthase.</p> <p>Conclusions</p> <p>The traditional application of the extract is confirmed by our experimental data. Due to its potential to inhibit critical receptor tyrosine kinases involved in HCC progression via the IGF-1 signaling pathway and NF-κB, the standardized <it>L.obtusiloba </it>extract should be further analysed for its active compounds and explored as (complementary) treatment option for HCC.</p

    Strict selection alone of patients undergoing liver transplantation for hilar cholangiocarcinoma is associated with improved survival

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    Liver transplantation for hilar cholangiocarcinoma (hCCA) has regained attention since the Mayo Clinic reported their favorable results with the use of a neo-adjuvant chemoradiation protocol. However, debate remains whether the success of the protocol should be attributed to the neo-adjuvant therapy or to the strict selection criteria that are being applied. The aim of this study was to investigate the value of patient selection alone on the outcome of liver transplantation for hCCA. In this retrospective study, patients that were transplanted for hCCA between1990 and 2010 in Europe were identified using the European Liver Transplant Registry (ELTR). Twenty-one centers reported 173 patients (69%) of a total of 249 patients in the ELTR. Twenty-six patients were wrongly coded, resulting in a study group of 147 patients. We identified 28 patients (19%) who met the strict selection criteria of the Mayo Clinic protocol, but had not undergone neo-adjuvant chemoradiation therapy. Five-year survival in this subgroup was 59%, which is comparable to patients with pretreatment pathological confirmed hCCA that were transplanted after completion of the chemoradiation protocol at the Mayo Clinic. In conclusion, although the results should be cautiously interpreted, this study suggests that with strict selection alone, improved survival after transplantation can be achieved, approaching the Mayo Clinic experience
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