Publications by authors named "Martina Heller"

In atom probe tomography, the spatial resolution and accuracy of the data critically depend on the 3D reconstruction of the 2D detector data. Atom probes with a reflectron have an improved mass resolving power and must include a model of the imaging properties of the reflectron. However, for modern wide-angle reflectron instruments, these imaging properties are not trivial and need to be determined for the reflectron used.

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Atom probe tomography (APT) data analytics have traditionally been based on manual analytics by researchers. As newer atom probes together with focused ion beam-based specimen preparation have opened APT to many more materials, yielding much more complex mass spectra, building up a systematic understanding of the pathway from raw data to final interpretation has increasingly become important. This demands a system in which the data and treatment can be traced, ideally by any interested party.

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To detect hydrogen in materials at the atomic scale, atom probe tomography is now regularly used. In order to avoid cumbersome cryo-preparation to suppress diffusion, often hydrogen is charged only into the finished specimen. Here, the use of hydrogen gas over electrochemical hydrogen has the advantage that the specimen is not contaminated with an electrolyte.

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Background: Renal cell carcinoma (RCC) is among the most lethal urologic malignancies once metastatic. Current treatment approaches for metastatic RCC (mRCC) involve immune checkpoint inhibitors (ICIs) that target the PD-L1/PD-1 axis. High PD-L1 expression in tumor tissue has been identified as a negative prognostic factor in RCC.

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Introduction. The COVID-19 pandemic has had a profound impact on the health of young people worldwide, especially on people with eating disorders (EDs) due to the stress, anxiety, and changes experienced in access to health care. Objective.

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  • Scientists created a new type of liquid metal catalyst called SCALMS, which helps speed up chemical reactions and is resistant to problems like coking (which is when unwanted carbon builds up).
  • They tested SCALMS using certain metals (like Co, Cu, Fe, and Ni) combined with gallium, to see how well they worked at high temperatures and in reactions involving methane.
  • While most catalysts had issues with oxidation (a chemical reaction with oxygen), the Ga-Ni SCALMS worked better, but there was a problem because they also lost gallium over time during the tests.
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Supported catalytically active liquid metal solutions (SCALMS) of Pt in Ga (2 at.-% Pt) were studied in the temperature range of 500 to 600 °C for propane dehydrogenation. A facile synthesis procedure using ultrasonication was implemented and compared to a previously reported organo-chemical route for gallium deposition.

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Background: Mutations in DNA damage repair genes, in particular genes involved in homology-directed repair, define a subgroup of men with prostate cancer with a more unfavorable prognosis but a therapeutic vulnerability to PARP inhibition. In current practice, mutational testing of prostate cancer patients is commonly done late i.e.

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Atom probe tomography (APT) is a powerful technique to obtain 3D chemical and structural information, however the 'standard' atom probe experimental workflow involves transfer of specimens at ambient conditions. The ability to transfer air- or thermally-sensitive samples between instruments while maintaining environmental control is critical to prevent chemical or morphological changes prior to analysis for a variety of interesting sample materials. In this article, we describe a versatile transfer system that enables cryogenic- or room-temperature transfer of specimens in vacuum or atmospheric conditions between sample preparation stations, a focused ion beam system (Zeiss Crossbeam 540) and a widely used commercial atom probe system (CAMECA LEAP 4000X HR).

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  • Scientists found that special cells called stromal cells help prostate cancer grow and change.
  • They looked at a growth factor called FGF-2 that is important in different stages of the cancer.
  • Their research showed that FGF-2 can cause problems with chromosomes that leads to cancer getting worse, and they tested this using lab experiments and mice with human cancer cells.
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A venous tumor thrombus (VTT) is a potentially lethal complication of renal cell carcinoma (RCC) but virtually nothing is known about the underlying natural history. Based on our observation that venous thrombi contain significant numbers of viable tumor cells, we applied multiregion whole exome sequencing to a total of 37 primary tumor and VTT samples including normal tissue specimens from five consecutive patients. Our findings demonstrate mutational heterogeneity between primary tumor and VTT with 106 of 483 genes (22%) harboring functional SNVs and/or indels altered in either primary tumor or thrombus.

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This case report shows the high PSMA-uptake in a patient with an adenoid cystic carcinoma of the maxillary sinus. Due to the intense ligand-uptake additional information for target volume delineation was obtained and the Treatment plan for bimodal radiotherapy with carbon ions was adapted accordingly.

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Background: Overexpression of the androgen receptor (AR) splice variant 7 (AR-V7) has recently been reported to be associated with resistance to antihormonal therapy. Herein, we address the question whether tumor cells with AR-V7 expression can be detected at the time of radical prostatectomy, that is, before long-term hormonal manipulation and castration resistance, and what the potential prognostic impact on the biochemical recurrence (BCR)-free survival may be.

Methods: An anti-AR-V7 antibody was first validated in a training set of prostate cancer specimens by a comparison of AR-V7 protein to AR-V7 mRNA expression.

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Background: APOBECs (apolipoprotein B mRNA-editing catalytic polypeptides) are cytidine deaminases that have been implicated in the host defense against viruses by blocking viral replication. They have also been shown to play a role in genome hypermutation in several human cancers. An APOBEC3 hypermutation signature has been discovered in cervical cancer, which is intimately associated with infection by high-risk human papillomaviruses (HPVs).

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Mutations in BRCA1 or BRCA2 define a subset of prostate cancer patients. Herein, we address the question whether BRCA1/2 mutations have a predictive impact on chemotherapy with docetaxel, a widely used drug in patients with metastatic castration resistant prostate cancer (mCRPC). Fifty-three men treated with docetaxel for mCRPC were tested for somatic BRCA1/2 mutations of the primary tumor.

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Ga-prostate-specific membrane antigen (PSMA)-11 PET/CT represents an advanced method for the staging of primary prostate cancer (PCa) and diagnosis of recurrent or metastatic PCa. However, because of the narrow availability of Ga the development of alternative tracers is of high interest. The objective of this study was to examine the value of the new PET tracer F-PSMA-1007 for the staging of local disease by comparing it with multiparametric MRI (mpMRI) and radical prostatectomy (RP) histopathology.

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Background: Taxanes are routinely used to treat men with advanced prostate cancer, yet their molecular mode of action is poorly characterized. Taxanes stabilize microtubules and may hence interfere with a plethora of cellular processes, most notably mitosis. However, prostate cancer is typically a slowly growing tumor suggesting that additional processes play a role in the response to taxanes.

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Cardiovascular disease remains a major cause of morbidity and mortality worldwide. Current medical practice takes into account information based on population studies and benefits observed in large populations or cohorts. However, individual patients present great differences in both toxicity and clinical efficacy that can be explained by variations in adherence, unknown drug to drug interactions and genetic variability.

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