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81.
JD Kuhlmann H Schwarzenbach P Wimberger M Poetsch R Kimmig S Kasimir-Bauer 《BMC cancer》2012,12(1):325
ABSTRACT: BACKGROUND: We recently showed that LOH proximal to M6P/IGF2R locus (D6S1581) in primary ovarian tumors is predictive for the presence of disseminated tumor cells (DTC) in the bone marrow (BM). For therapy-monitoring, it would be highly desirable to establish a blood-based biomarker. Therefore, we quantified circulating DNA (cirDNA) in sera of 63 ovarian cancer patients before surgery and after chemotherapy, measured incidence of LOH at four cancer-relevant chromosomal loci, correlated LOH with tumor cell spread to the BM and evaluated prognostic significance of LOH. Patients and Methods: cirDNA was fractionated into high- and low molecular-weight fraction (HMWF, LMWF) for LOH-profiling, utilizing PCR-based fluorescence microsatellite analysis. BM aspirates were analyzed for DTC by immunocytochemistry using the pan-cytokeratin antibody A45-B/B3. RESULTS: cirDNA levels in the HMWF before surgery were predictive for residual tumor load (p=0.017). After chemotherapy, we observed a significant decline of cirDNA in the LMWF (p=0.0001) but not in the HMWF. LOH was prevalently detected in the LMWF with an overall frequency of 67 %, only moderately ablating after chemotherapy (45 %). Before surgery, LOH in the LMWF at marker D10S1765 and D13S218 significantly correlated with tumor grading and FIGO stage (p=0.033, p=0.004, respectively). In both combined fractions, LOH at D6S1581 additionally associated with overall survival (OS) (p=0.030). Moreover, solely LOH at D10S1765 in LMWF after therapy correlated with DTC in BM after therapy (p=0.017). CONCLUSION: We demonstrate the applicability and necessity of DNA-fractionation prior to analyzing circulating LOH and identify LOH at D10S1765 and D6S1581 as novel blood-based biomarkers for ovarian cancer, being relevant for therapy-monitoring. 相似文献
82.
Volkmar Müller Sabine Riethdorf Brigitte Rack Wolfgang Janni Peter A Fasching Erich Solomayer Bahriye Aktas Sabine Kasimir-Bauer Klaus Pantel Tanja Fehm 《Breast cancer research : BCR》2012,14(4):1-8
Introduction
There is a multitude of assays for the detection of circulating tumor cells (CTCs) but a very limited number of studies comparing the clinical relevance of results obtained with different test methods. The DETECT trial for metastatic breast cancer patients was designed to directly compare the prognostic impact of two commercially available CTC assays that are prominent representatives of immunocytochemical and RT-PCR based technologies.Methods
In total, 254 metastatic breast cancer patients were enrolled in this prospective multicenter trial. CTCs were assessed using both the AdnaTest Breast Cancer and the CellSearch system according to the manufacturers' instructions.Results
With the CellSearch system, 116 of 221 (50%) evaluable patients were CTC-positive based on a cut-off level at 5 or more CTCs. The median overall survival (OS) was 18.1 months in CTC-positive patients. (95%-CI: 15.1-22.1 months) compared to 27 months in CTC-negative patients (23.5-30.7 months; p<0.001). This prognostic impact for OS was also significant in the subgroups of patients with triple negative, HER2-positive and hormone receptor-positive/HER2-negative primary tumors. The progression free survival (PFS) was not correlated with CTC status in our cohort receiving different types and lines of systemic treatment (p = 0.197). In multivariate analysis, the presence of CTCs was an independent predictor for OS (HR: 2.7, 95%-CI: 1.6-4.2). When the AdnaTest Breast was performed, 88 of 221 (40%) patients were CTC-positive. CTC-positivity assessed by the AdnaTest Breast had no association with PFS or OS.Conclusions
The prognostic relevance of CTC detection in metastatic breast cancer patients depends on the test method. The present results indicate that the CellSearch system is superior to the AdnaTest Breast Cancer in predicting clinical outcome in advanced breast cancer.Trial registration
Current Controlled Trials Registry number ISRCTN59722891. 相似文献83.
Vanderzwalmen P Hiemer A Rubner P Bach M Neyer A Stecher A Uher P Zintz M Lejeune B Vanderzwalmen S Cassuto G Zech NH 《Reproductive biomedicine online》2008,17(5):617-627
Spermatozoa selection at high magnification before intracytoplasmic sperm injection seems to be positively associated with pregnancy rates after day 3 embryo transfers. The aim was to demonstrate an association between the presence of vacuoles in sperm nuclei and the competence of embryos to develop to day 5. Grading of spermatozoa at x 6000-x 12,500 magnification: grade I, no vacuoles; grade II, or=1 large vacuole; grade IV, large vacuoles with other abnormalities. The outcome of embryo development in a group of 25 patients after sibling oocyte injection with the four different grades of spermatozoa showed no significant difference in embryo quality up to day 3. However, the occurrence of blastocyst formation was 56.3 and 61.4% with grade I and II spermatozoa respectively, compared with 5.1% with grade III and 0% with grade IV respectively (P < 0.001). Spermatozoa selection at high magnification using Nomarski interference contrast is useful to identify more precisely the size and the number of nuclear vacuoles that greatly exert a negative effect on embryo development to the blastocyst stage. These observations confirm previous studies pointing to possible 'early and late paternal effects', both of which may have an impact on early embryonic development. 相似文献
84.
Estour F Ménager S Akagah B Lafont O 《European journal of medicinal chemistry》2003,38(11-12):925-928
In order to examine the biotransformations of xenobiotics, it is essential to realize studies of metabolism of drugs in living animals. It is generally difficult to extract quantitatively the metabolites from biological media or excreta. Alternative methods have then been developed. Application of such techniques to 4a-methylhexahydronaphthalenones, which constitute starting material for the stereospecific synthesis of terpenoids or steroids, is particularly demonstrative. By biosynthetical ways, it was not possible to access with good yields to all the metabolites obtained in vivo. A novel methodology, based on the use of a manganoporphyrin catalyst, allowed to synthesize large amounts of several models of metabolites corresponding to those which had been isolated in living rats. Only one of the metabolites obtained in vivo could not be synthesized by this biomimetic system. This proved that alternative methods are precious to obtain models with good yields, but need to be validated by controls in living animals. 相似文献
85.
Michael R. van Gerven Eva Bozsaky Yvette A. H. Matser Julian Vosseberg Sabine TaschnerMandl Jan Koster Godelieve A. M. Tytgat Jan J. Molenaar Marlinde van den Boogaard 《Cancer science》2022,113(6):2167
Neuroblastoma is the most common extracranial solid tumor in children. The chromatin remodeler ATRX is frequently mutated in high‐risk patients with a poor prognosis. Although many studies have reported ATRX aberrations and the associated clinical characteristics in neuroblastoma, a comprehensive overview is currently lacking. In this study, we extensively characterize the mutational spectrum of ATRX aberrations in neuroblastoma tumors reported in previous studies and present an overview of patient and tumor characteristics. We collected the data of a total of 127 neuroblastoma patients and three cell lines with ATRX aberrations originating from 20 papers. We subdivide the ATRX aberrations into nonsense, missense, and multiexon deletions (MEDs) and show that 68% of them are MEDs. Of these MEDs, 75% are predicted to be in‐frame. Furthermore, we identify a missense mutational hotspot region in the helicase domain. We also confirm that all three ATRX mutation types are more often identified in patients diagnosed at an older age, but still approximately 40% of the patients are aged 5 years or younger at diagnosis. Surprisingly, we found that 11q deletions are enriched in neuroblastomas with ATRX deletions compared to a reference cohort, but not in neuroblastomas with ATRX point mutations. Taken together, our data emphasizes a distinct ATRX mutation spectrum in neuroblastoma, which should be considered when studying molecular phenotypes and therapeutic strategies. 相似文献
86.
Tessa Brik Lieke J.J.J. Vrouenraets Sebastian E.E. Schagen Andreas Meissner Martine C. de Vries Sabine E. Hannema 《The Journal of adolescent health》2019,64(5):589-593
Purpose
The primary aims of the study are to examine the rate of attempted fertility preservation (FP) among a Dutch cohort of transgirls who started gonadotropin-releasing hormone analog treatment and the reasons why adolescents did or did not choose to attempt FP.Methods
The study was a single-center retrospective review of medical records of 35 transgirls who started gonadotropin-releasing hormone analog treatment between 2011 and 2017.Results
Ninety-one percent of adolescents were counseled on the option of FP. Thirty-eight percent of counseled adolescents attempted FP, and 75% of them were able to cryopreserve sperm suitable for intrauterine insemination or intracytoplasmic sperm injection. Younger and Caucasian transgirls were less likely to attempt FP. No specific reason for declining FP was known in 33% adolescents, 32% of adolescents were not able to produce a semen sample because of early puberty, 17% felt uncomfortable with masturbation, 17% did not want to have children, and 13% wanted to adopt.Conclusions
One third of adolescents attempted FP, which is much more than the percentage reported in previous studies from the United States. One third of the transgirls could not make use of FP because they were unable to produce a semen sample because of early pubertal stage. For these adolescents, alternatives need to be explored. 相似文献87.
Sabine Hummel Katharina Obermeier Katja Zier Sandra Krommes Michael Schemme Peter Karlinger 《Materials》2022,15(11)
Increasing demand for energy-efficient means of transport has steadily intensified the trend towards lightweight components. Thermoplastic glass fiber composites (organo sheets) play a major role in the production of functional automotive components. Organo sheets are cut, shaped and functionalized by injection molding to produce hybrid components, such as those used in car door modules. The cutting process produces a considerable amount of production waste, which has thus far been thermally recycled. This study develops a closed mechanical recycling process and analyzes the different steps of the process. The offcuts were shredded using two shredding methods and implemented directly in the injection-molding process. Using tensile tests and impact bending tests, the material properties of the recycled materials were compared with the virgin material. In addition, fiber length degradation via the injection-molding process and the influence of the waterjet-cutting process on the mechanical properties are investigated. Recycled offcuts are both comparable to new material in terms of mechanical properties and usability, and are also economically and ecologically advantageous. Recycling polypropylene waste with glass fiber reinforcement in a closed loop is an effective way to reduce industrial waste in a sustainable and economical production process. 相似文献
88.
Dominik N?rz Susanne Pfefferle Thomas Brehm Gefion Franke Ilka Grewe Birte Knobling Martin Aepfelbacher Samuel Huber Eva M. Klupp Sabine Jordan Marylyn M. Addo Julian Schulze zur Wiesch Stefan Schmiedel Marc Lütgehetmann Johannes K. Knobloch 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(26)
89.
Occult lung infarction may induce false interpretation of 18F-FDG PET in primary staging of pulmonary malignancies 总被引:3,自引:0,他引:3
Kamel EM McKee TA Calcagni ML Schmidt S Markl S Castaldo S Delaloye AB 《European journal of nuclear medicine and molecular imaging》2005,32(6):641-646
Purpose The aim of the present report is to describe abnormal 18F-fluorodeoxyglucose (FDG) accumulation patterns in the pleura and lung parenchyma in a group of lung cancer patients in whom lung infarction was present at the time of positron emission tomography (PET).Methods Between November 2002 and December 2003, a total of 145 patients (102 males, 43 females; age range 38–85 years) were subjected to whole-body FDG PET for initial staging (n=117) or restaging (n=11) of lung cancer or for evaluation of solitary pulmonary nodules (n=17). Of these patients, 24 displayed abnormal FDG accumulation in the lung parenchyma that was not consistent with the primary lesion under investigation (ipsilateral n=12, contralateral n=9 or bilateral n=3). Without correlative imaging, this additional FDG uptake would have been considered indeterminate in differential diagnosis.Results Of the 24 patients who were identified as having such lesions, six harboured secondary tumour nodules diagnosed as metastases, while in three the diagnosis of a synchronous second primary lung tumour was established. Additionally, nine patients were identified as having post-stenotic pneumonia and/or atelectasis (n=6) or granulomatous lung disease (n=3). In the remaining six (4% of all patients), a diagnosis of recent pulmonary embolism that topographically matched the additional FDG accumulation (SUVmax range 1.4–8.6, mean 3.9) was made. Four of these six patients were known to have pulmonary embolism, and hence false positive interpretation was avoided by correlating the PET findings with those of the pre-existing diagnostic work-up. The remaining two patients were harbouring small occult infarctions that mimicked satellite nodules in the lung periphery. Based on histopathological results, the abnormal FDG accumulation in these two patients was attributed to the inflammatory reaction and tissue repair associated with the pathological cascade of pulmonary embolism.Conclusion In patients with pulmonary malignancies, synchronous lung infarction may induce pathological FDG accumulation that can mimic active tumour manifestations. Identifying this potential pitfall may allow avoidance of false positive FDG PET interpretation. 相似文献
90.
Material differentiation by dual energy CT: initial experience 总被引:9,自引:0,他引:9
Johnson TR Krauss B Sedlmair M Grasruck M Bruder H Morhard D Fink C Weckbach S Lenhard M Schmidt B Flohr T Reiser MF Becker CR 《European radiology》2007,17(6):1510-1517
The aim of this study was to assess the feasibility of a differentiation of iodine from other materials and of different body
tissues using dual energy CT. Ten patients were scanned on a SOMATOM Definition Dual Source CT (DSCT; Siemens, Forchheim,
Germany) system in dual energy mode at tube voltages of 140 and 80 kVp and a ratio of 1:3 between tube currents. Weighted
CT Dose Index ranged between 7 and 8 mGy, remaining markedly below reference dose values for the respective body regions.
Image post-processing with three-material decomposition was applied to differentiate iodine or collagen from other tissue.
The results showed that a differentiation and depiction of contrast material distribution is possible in the brain, the lung,
the liver and the kidneys with or without the underlying tissue of the organ. In angiographies, bone structures can be removed
from the dataset to ease the evaluation of the vessels. The differentiation of collagen makes it possible to depict tendons
and ligaments. Dual energy CT offers a more specific tissue characterization in CT and can improve the assessment of vascular
disease. Further studies are required to draw conclusions on the diagnostic value of the individual applications. 相似文献