Publications by authors named "Thomas Gunther"

Article Synopsis
  • A new derivative of minigastrin, DOTA-CCK-66, shows promising results in imaging and therapy for medullary thyroid carcinoma (MTC) when labeled with either Gallium (Ga) or Actinium (Ac).
  • In a study using tumor-bearing mice, treatment with either Lu- or Ac-labeled DOTA-CCK-66 significantly reduced tumor growth and increased survival times compared to a control group treated with Ga-labeled DOTA-CCK-66.
  • The Ac-labeled treatment resulted in the highest mean survival rate, indicating its strong therapeutic potential for MTC in future patient management.
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Merkel cell polyomavirus (MCPyV) is the causative agent of the majority of Merkel cell carcinomas (MCC). The virus has limited coding capacity, with its early viral proteins, large T (LT) and small T (sT), being multifunctional and contributing to infection and transformation. A fundamental difference in early viral gene expression between infection and MCPyV-driven tumorigenesis is the expression of a truncated LT (LTtr) in the tumor.

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Abstract: Cholecystokinin 2 receptor (CCK 2 R) is a promising target for imaging and treatment of medullary thyroid cancer due to its overexpression in over 90% of tumor cells. 68 Ga-DOTA-CCK-66 is a recently introduced PET tracer selective for CCK 2 R, which has shown favorable pharmacokinetics in vivo in preclinical experiments. In order to further investigate safety and suitability of this tracer in the human setting, whole-body distribution and radiation dosimetry were evaluated.

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Incidents of waste and biofuel fires are common at all stages of the waste recycling chain and have grave implications for business, employees, firefighters, society, and environment. An early detection of waste and biofuel fires in the smouldering stage could save precious lives, resources, and our environment. Existing fire detection methodologies e.

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Background: In patients with prostate cancer (PCa), imaging with gastrin-releasing peptide receptor (GRPR) ligands is an alternative to PSMA-targeted tracers, particularly if PSMA expression is low or absent. [Tc]Tc-N4-BTG is a newly developed GRPR-directed probe for conventional scintigraphy and single photon emission computed tomography (SPECT) imaging. The current study aims to investigate the safety, biodistribution and dosimetry of [Tc]Tc-N4-BTG in patients with biochemical recurrence (BCR) of PCa.

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Background: We recently introduced radiohybrid (rh)-based minigastrin analogs e.g., DOTA-rhCCK-18 (DOTA-D-Dap(p-SiFA)-(D-γ-Glu)-Ala-Tyr-Gly-Trp-Nle-Asp-Phe-NH), that revealed substantially increased activity retention in the tumor.

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Herpesviruses are large DNA viruses and include important human and veterinary pathogens. Their genomes can be cloned as bacterial artificial chromosomes (BACs) and genetically engineered in Escherichia coli using BAC recombineering methods. While the recombineering methods are efficient, the initial BAC-cloning step remains laborious.

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To elucidate potential benefits of the Auger-electron-emitting radionuclide Tb, we compared the preclinical performance of the gastrin-releasing peptide receptor antagonists RM2 (DOTA-Pip-d-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH) and AMTG (α-Me-Trp-RM2), each labeled with both Lu and Tb. Tb/Lu labeling (90°C, 5 min) and cell-based experiments (PC-3 cells) were performed. In vivo stability (30 min after injection) and biodistribution studies (1-72 h after injection) were performed on PC-3 tumor-bearing CB17-SCID mice.

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Because of the need for radiolabeled theranostics for the detection and treatment of medullary thyroid cancer (MTC), and the yet unresolved stability issues of minigastrin analogs targeting the cholecystokinin-2 receptor (CCK-2R), our aim was to address in vivo stability, our motivation being to develop and evaluate DOTA-CCK-66 (DOTA-γ-glu-PEG-Trp-(-Me)Nle-Asp-1-Nal-NH, PEG: polyethylene glycol) and DOTA-CCK-66.2 (DOTA-glu-PEG-Trp-(-Me)Nle-Asp-1-Nal-NH), both derived from DOTA-MGS5 (DOTA-glu-Ala-Tyr-Gly-Trp-(-Me)Nle-Asp-1-Nal-NH), and clinically translate [Ga]Ga-DOTA-CCK-66. Cu and Ga labeling of DOTA-CCK-66, DOTA-CCK-66.

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Despite the recent success of prostate-specific membrane antigen (PSMA)-targeted compounds for theranostic use in prostate cancer (PCa), alternative options for the detection and treatment of PSMA-negative lesions are needed. We have recently developed a novel gastrin-releasing peptide receptor (GRPR) ligand with improved metabolic stability, which might improve diagnostic and therapeutic efficacy and could be valuable for PSMA-negative PCa patients. Our aim was to examine its suitability for theranostic use.

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The multifunctional adenovirus E1B-55K oncoprotein can induce cell transformation in conjunction with adenovirus E1A gene products. Previous data from transient expression studies and in vitro experiments suggest that these growth-promoting activities correlate with E1B-55K-mediated transcriptional repression of p53-targeted genes. Here, we analyzed genome-wide occupancies and transcriptional consequences of species C5 and A12 E1B-55Ks in transformed mammalian cells by combinatory ChIP and RNA-seq analyses.

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Purpose: Many models of language comprehension assume that listeners predict the continuation of an incoming linguistic stimulus immediately after its onset, based on only partial linguistic and contextual information. Their related developmental models try to determine which cues (e.g.

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Here, we describe the complete genome sequence of a blood culture isolate from a catheter-related bloodstream infection in a male patient.

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Self-assembled supramolecular coordination complexes (SCCs) hold promise for biomedical applications in cancer therapy, although their potential in the field of nuclear medicine is still substantially unexplored. Therefore, in this study an -functionalized cationic [PdL] metallacycle (L = 3,5-bis(3-ethynylpyridine)phenyl), targeted to the somatostatin-2 receptor (sst2R) and featuring the DOTA chelator (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) in order to bind the β- and γ-emitter lutetium-177, was synthesized by self-assembly following ligand synthesis via standard solid-phase peptide synthesis (SPPS). This metallacycle was then characterized by reverse-phase high-performance liquid chromatography (RP-HPLC), electrospray ionization mass spectrometry (ESI-MS), and H and H-DOSY NMR (DOSY = diffusion-ordered spectroscopy).

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Background: Over the last years, several strategies have been reported to improve the metabolic stability of minigastrin analogs. However, currently applied compounds still reveal limited in vitro and in vivo stability. We thus performed a glycine scan at the N-terminus of DOTA-MGS5 (DOTA-D-Glu-Ala-Tyr-Gly-Trp-(N-Me)Nle-Asp-1-Nal) to systematically analyze the peptide structure.

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Induction of type I interferon (IFN) gene expression is among the first lines of cellular defense a virus encounters during primary infection. We previously identified the tegument protein M35 of murine cytomegalovirus (MCMV) as an essential antagonist of this antiviral system, showing that M35 interferes with type I IFN induction downstream of pattern-recognition receptor (PRR) activation. Here, we report structural and mechanistic details of M35's function.

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In order to optimize elevated kidney retention of previously reported minigastrin derivatives, we substituted ()-DOTAGA by DOTA in ()-DOTAGA-rhCCK-16/-18. CCK-2R-mediated internalization and affinity of the new compounds were determined using AR42J cells. Biodistribution and SPECT/CT imaging studies at 1 and 24 h p.

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Background: Radioguided surgery (RGS) has recently emerged as a valuable new tool in the management of recurrent prostate cancer (PCa). After preoperative injection of a Tc-labeled prostate-specific membrane antigen (PSMA) inhibitor, radioguided intraoperative identification and resection of lesions is facilitated by means of suitable γ-probes. First clinical experiences show the feasibility of RGS and suggest superiority over conventional lymph node dissection in recurrent PCa.

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In order to enable F- and Lu-labelling within the same molecule, we introduced a silicon-based fluoride acceptor (SiFA) into the hexa-D-glutamate chain of DOTA-PP-F11N. In addition, minigastrin analogues with a prolonged as well as -linked D-glutamate chain were synthesised and evaluated. CCK-2R affinity (, AR42J cells) and lipophilicity (log) were determined.

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Current radiolabeled gastrin-releasing peptide receptor (GRPR) ligands usually suffer from high accumulation in GRPR-positive organs (pancreas, stomach), limiting tumor-to-background contrast in the abdomen. In novel N4-bombesin derivatives this was addressed by substitutions at the Gln7-Trp8 site within the MJ9 peptide (H-Pip5-phe6-Gln7-Trp8-Ala9-Val10-Gly11-His12-Sta13-Leu14-NH2) either by homoserine (Hse7), β-(3-benzothienyl) alanine (Bta8) or α-methyl tryptophan (α-Me-Trp8), with the aim of optimizing pharmacokinetics. We prepared and characterized the peptide conjugates 6-carboxy-1,4,8,11-tetraazaundecane (N4)-asp-MJ9, N4-asp-[Bta8]MJ9, N4-[Hse7]MJ9 and N4-[α-Me-Trp8]MJ9, and evaluated these compounds in vitro (GRPR affinity via IC50,inverse; internalization; lipophilicity via logD7.

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We here investigate the impact of antiviral treatments such as remdesivir on intra-host genomic diversity and emergence of SARS-CoV2 variants in patients with a prolonged course of infection. Sequencing and variant analysis performed in 112 longitudinal respiratory samples from 14 SARS-CoV2-infected patients with severe disease progression show that major frequency variants do not generally arise during prolonged infection. However, remdesivir treatment can increase intra-host genomic diversity and result in the emergence of novel major variant species harboring fixed mutations.

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Background: The ongoing monkeypox virus outbreak includes at least 7553 confirmed cases in previously non-endemic countries worldwide as of July 2022. Clinical presentation has been reported as highly variable, sometimes lacking classically described systemic symptoms, and only small numbers of cutaneous lesions in most patients. The aim of this study was to compare clinical data with longitudinal qPCR results from lesion swabs, oropharyngeal swabs and blood in a well characterized patient cohort.

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