Publications by authors named "Behrens A"

Modern high-resolution video endoscopes allow detailed examination of the esophageal mucosa and diagnosis of early neoplastic changes in the gastrointestinal tract. Whereas Barrett's esophagus is a precancerous condition that can develop into adenocarcinoma, there is no defined precancerous lesion for squamous cell carcinoma. Various diseases are associated with the development of esophageal squamous cell carcinoma.

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c-Jun, the major component of the AP-1 transcription factor complex, has important functions in cellular proliferation and oncogenic transformation. The RING domain-containing protein RACO-1 functions as a c-Jun coactivator that molecularly links growth factor signalling to AP-1 transactivation. Here we demonstrate that RACO-1 is present as a nuclear dimer and that c-Jun specifically interacts with dimeric RACO-1.

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The regulation of cardiac differentiation is complex and incompletely understood. Recent studies have documented that Nkx2-5-positive cells are not limited to the cardiac lineage, but can give rise to endothelial and smooth muscle lineages. Other work has elucidated that, in addition to promoting cardiac development, Nkx2-5 plays a larger role in mesodermal patterning although the transcriptional networks that govern this developmental patterning are undefined.

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Article Synopsis
  • - Cancer chromosomal instability (CIN) leads to frequent changes in chromosome number and structure, resulting in diverse tumor cell populations and is linked to poor outcomes and drug resistance.
  • - In this study, researchers found that CIN(+) colorectal cancer (CRC) cells experience impaired DNA replication and increased replication stress compared to CIN(-) CRC cells, contributing to chromosome missegregation during cell division.
  • - The researchers identified three new genes that suppress CIN, which are often lost in CIN(+) CRC, and showed that addressing replication stress could reduce chromosome segregation errors, suggesting potential new treatment strategies to improve cancer outcomes.
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Background & Aims: Patients with early-stage mucosal (T1a) esophageal adenocarcinoma (EAC) are increasingly treated by endoscopic resection. EACs limited to the upper third of the submucosa (pT1b sm1) could also be treated by endoscopy. We assessed the efficacy, safety, and long-term effects of endoscopic therapy for these patients.

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The hereditary autosomal recessive disease ataxia telangiectasia (A-T) is caused by mutation in the DNA damage kinase ATM. ATM's main function is to orchestrate DNA repair, thereby maintaining genomic stability. ATM activity is increased in response to several stimuli, including ionising radiation (IR) and hypotonic stress.

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Ataxia telangiectasia mutated (ATM) protein kinase activation by DNA double-strand breaks (DSBs) requires the Mre11-Rad50-NBS1 (MRN) complex, whereas ATM interactor (ATMIN) protein is required for ATM signaling induced by changes in chromatin structure. We show here that NBS1 and ATMIN proteins compete for ATM binding and that this mechanism controls ATM function. DSB-induced ATM substrate phosphorylation was increased in atmin mutant cells.

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We report on a search for particle dark matter with the XENON100 experiment, operated at the Laboratori Nazionali del Gran Sasso for 13 months during 2011 and 2012. XENON100 features an ultralow electromagnetic background of (5.3 ± 0.

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Background: The introduction of the S3 guideline on "Sedation in Gastrointestinal Endoscopy" in 2008 led to substantial organisational, structural, staffing-related, financial, and legal changes in the everyday work of departments of gastrointestinal endoscopy. This study examines the economic effects of this and the change in the legal situation. In addition, the extent to which the guideline has been implemented was assessed using an electronic questionnaire circulated to the members of the Working Group of Head Gastroenterologists in Hospitals (ALGK).

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The radical response of peripheral nerves to injury (Wallerian degeneration) is the cornerstone of nerve repair. We show that activation of the transcription factor c-Jun in Schwann cells is a global regulator of Wallerian degeneration. c-Jun governs major aspects of the injury response, determines the expression of trophic factors, adhesion molecules, the formation of regeneration tracks and myelin clearance and controls the distinctive regenerative potential of peripheral nerves.

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Cocaine-dependent women, relative to their male counterparts, report shorter cocaine-free periods and report transiting faster from first use to entering treatment for addiction. Similarly, preclinical studies indicate that female rats, particularly those in the estrus phase of their reproductive cycle, show increased operant responding for cocaine under a wide variety of schedules. Making maladaptive choices is a component of drug dependence, and concurrent reinforcement schedules that examine cocaine choice offers an animal model of the conditions of human drug use; therefore, the examination of sex differences in decision-making may be critical to understanding why women display a more severe profile of cocaine addiction than men.

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Notch signaling controls fundamental aspects of angiogenic blood vessel growth including the selection of sprouting tip cells, endothelial proliferation and arterial differentiation. The E3 ubiquitin ligase Fbxw7 is part of the SCF protein complex responsible for the polyubiquitination and thereby proteasomal degradation of substrates such as Notch, c-Myc and c-Jun. Here, we show that Fbxw7 is a critical regulator of angiogenesis in the mouse retina and the zebrafish embryonic trunk, which we attribute to its role in the degradation of active Notch.

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Objective: The aim of this study was to investigate whether pulsations measured in the brain correspond to those measured in lumbar space, and subsequently whether lumbar punctures could replace invasive recordings.

Methods: In ten patients with normal pressure hydrocephalus, simultaneous recordings of the intracranial pressure (ICP; intraparenchymal) and lumbar pressure (LP; cerebrospinal fluid pressure) were performed. During registration, pressure was altered between resting pressure and 45 mmHg using an infusion test.

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The AP-1 transcription factor c-Jun is a master regulator of the axonal response in neurons. c-Jun also functions as a negative regulator of myelination in Schwann cells (SCs) and is strongly reactivated in SCs upon axonal injury. We demonstrate here that, after injury, the absence of c-Jun specifically in SCs caused impaired axonal regeneration and severely increased neuronal cell death.

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Small bowel intussusception is a rare cause of abdominal pain in adult patients. Due to varying symptoms and different underlying causes its diagnosis and treatment is challenging for physicians. This case report describes recurrent intussusception in an adult female patient and celiac disease could only be diagnosed as the cause of these symptoms after surgery.

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Pseudomonas aeruginosa is a Gram-negative, opportunistic pathogen that utilizes polar type IV pili (T4P) for twitching motility and adhesion in the environment and during infection. Pilus assembly requires FimX, a GGDEF/EAL domain protein that binds and hydrolyzes cyclic di-GMP (c-di-GMP). Bacteria lacking FimX are deficient in twitching motility and microcolony formation.

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Transcriptional heterogeneity within embryonic stem cell (ESC) populations has been suggested as a mechanism by which a seemingly homogeneous cell population can initiate differentiation into an array of different cell types. Chromatin remodeling proteins have been shown to control transcriptional variability in yeast and to be important for mammalian ESC lineage commitment. Here we show that the Nucleosome Remodeling and Deacetylation (NuRD) complex, which is required for ESC lineage commitment, modulates both transcriptional heterogeneity and the dynamic range of a set of pluripotency genes in ESCs.

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Non-small cell lung cancer (NSCLC) is the most frequent cause of cancer deaths worldwide; nearly half contain mutations in the receptor tyrosine kinase/RAS pathway. Here we show that RAS-pathway mutant NSCLC cells depend on the transcription factor GATA2. Loss of GATA2 reduced the viability of NSCLC cells with RAS-pathway mutations, whereas wild-type cells were unaffected.

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Purpose: To determine the effects of single radial or horizontal suture placement in 2-step clear corneal incision (CCI) wound apposition and permeability to particles of India ink.

Methods: Five fresh human globes were included. Two 25-gauge needles connected to a saline solution bag and to a digital manometer were inserted through the limbus, 120 degrees apart from each other.

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Neuroinflammation driven by the vanilloid-type ion channel receptor transient receptor potential vanilloid type 1 (TRPV-1) is suspected to play a role in the pathophysiology of inflammatory bowel disease. Because inflammatory bowel disease is known to elevate the risk of colon cancer, we examined postulated roles for TRPV-1-driven neuroinflammation in promoting colitis-associated and spontaneous colon cancer development. Using a well-established model of colitis-associated cancer (CAC), we found that mice genetically deficient in TRPV-1 showed a higher incidence and number of tumors in the distal colon.

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Although neural c-Jun is essential for successful peripheral nerve regeneration, the cellular basis of this effect and the impact of c-Jun activation are incompletely understood. In the current study, we explored the effects of neuron-selective c-Jun deletion, substitution of serine 63 and 73 phosphoacceptor sites with non-phosphorylatable alanine, and deletion of Jun N-terminal kinases 1, 2 and 3 in mouse facial nerve regeneration. Removal of the floxed c-jun gene in facial motoneurons using cre recombinase under control of a neuron-specific synapsin promoter (junΔS) abolished basal and injury-induced neuronal c-Jun immunoreactivity, as well as most of the molecular responses following facial axotomy.

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Purpose: To compare the effects of topical human amniotic fluid (HAF), topical human serum (HS), and topical artificial tears in a mouse model of dry eye.

Methods: Thirty C57BL/6 mice were divided into 3 treatment groups: HAF, HS, and preservative-free artificial tears. Dry eye was induced by an injection of botulinum toxin B (BTX-B) into the lacrimal gland.

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In minimal invasive surgery (MIS) a complete and seamless inspection of organs, e.g. the urinary bladder, using video endoscopes is often required for diagnostics.

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The usage of video endoscopes in cystoscopic interventions of the urinary bladder impedes an intuitive navigation. Although image-based solutions such as panorama images can provide extended views of the surgical field, a real-time 3-D navigation is not supported. Furthermore, the integration of common tracking systems in ambulant clinics is often hindered due to low usability and high costs.

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