22 results on '"Steinhorst K"'
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2. Überraschung in der Histologie bei einem chronischen Hornhautulkus
- Author
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Steinhorst, K. A., primary and Weller, J. M., additional
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- 2023
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3. G protein‐coupled receptor 40 expression in human melanoma – correlation with tumour thickness, AJCC stage and survival
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Kleemann, J., primary, Hrgovic, I., additional, Kleimann, P., additional, Ter‐Nedden, J., additional, Glaser, M., additional, Steinhorst, K., additional, Härle, K., additional, Müller, J., additional, Kaufmann, R., additional, Kippenberger, S., additional, and Meissner, M., additional
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- 2019
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4. G protein‐coupled receptor 40 expression in human melanoma – correlation with tumour thickness, AJCC stage and survival.
- Author
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Kleemann, J., Hrgovic, I., Kleimann, P., Ter‐Nedden, J., Glaser, M., Steinhorst, K., Härle, K., Müller, J., Kaufmann, R., Kippenberger, S., and Meissner, M.
- Subjects
G protein coupled receptors ,MICROPHTHALMIA-associated transcription factor ,MELANOMA ,UNSATURATED fatty acids ,FREE fatty acids ,TUMORS - Abstract
Background: In melanoma, preclinical data suggest a possible role of polyunsaturated fatty acids inhibiting cell growth. A new target molecule for free fatty acids, the G protein‐coupled receptor GPR40, was identified in melanoma cells. Objectives: The aim of this study was to investigate GPR40 expression in human melanocytic tissues and to evaluate its potential as a prognostic marker. Methods and Results: A total of 114 tissue sections of naevi, primary melanoma and melanoma metastasis were immunohistochemically stained with anti‐GPR40. The staining was evaluated, using the immunoreactivity scoring system. Compared to naevi, primary melanoma and melanoma metastasis showed significantly higher levels of GPR40 (P < 0.05). In primary melanoma, GPR40 expression positively correlated with tumour thickness (P = 0.044) and AJCC level (P = 0.017) and in melanoma metastasis with AJCC level (P = 0.035). Primary melanoma patients with high levels of GPR40 had a significantly poorer overall survival (P = 0.004) and shorter disease‐free survival (0.040). Conclusion: The present study identified GPR40 as a novel target molecule in melanoma. First evidence for a potential role of the receptor in tumour progression and metastases was found, and it could be demonstrated that GPR40 expression is negatively correlated with patient's survival. [ABSTRACT FROM AUTHOR]
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- 2020
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5. Exploring three-dimensional matrix-assisted laser desorption/ionization imaging mass spectrometry data
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Trede, D., Schiffler, S., Becker, M., Wirtz, S., Steinhorst, K., Strehlow, J., Aichler, M., Kobarg, J.H., Oetjen, J., Dyatloy, A., Heldmann, S., Walch, A., Thiele, H., Maass, P., Alexandrov, T., and Publica
- Abstract
Three-dimensional (3D) imaging has a significant impact on many challenges of life sciences. Three-dimensional matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) is an emerging label free bioanalytical technique capturing the spatial distribution of hundreds of molecular compounds in 3D by providing a MALDI mass spectrum for each spatial point of a 3D sample. Currently, 3D MALDI-LMS cannot tap its full potential due to the lack efficient computational methods for constructing, processing, and visualizing large and complex 3D MALDI-IMS data We present a new pipeline of efficient computational methods, which enables analysis and interpretation of a 3D MALDI-IMS data set. Construction of a MALDI-LMS data set was done according to the state-of-the-art protocols and involved sample preparation, spectra acquisition, spectra preprocessing, and registration of serial sections. For analysis and interpretation of 3D MALDI-IMS data, we applied the. spatial segmentation approach which is well-accepted in analysis of two-dimensional (2D) MALDI-IMS data. In line with 2D data analysis, we used edge-preserving 3D image denoising prior to segmentation to reduce strong and chaotic spectrum-to-spectrum variation. For segmentation, we used an efficient clustering method, called bisecting k-means, which is optimized for hierarchical clustering of a large 3D MALDI-IMS data set. Using the proposed pipeline, we analyzed a central part of a mouse. kidney using 33 serial sections of 3.5 mu m thickness after the PAXgene tissue fixation and paraffin embedding. For each serial section, a 2D MALDI-IMS data set was acquired following the standard protocols with the high spatial resolution of 50 mu m. Altogether, 512 495 mass spectra were acquired that corresponds to approximately 50 gigabytes of data After registration of serial sections into a 3D data set, our computational pipeline allowed us to reveal the 3D kidney anatomical structure based on mass spectrometry data only Finally, automated analysis discovered molecular masses colocalized with major anatomical regions In the same way, the proposed pipeline can be used for analysis and interpretation of any 3D MALDI-IMS data set in particular of pathological cases.
- Published
- 2012
6. Using mark-recapture data in an individual-based model to evaluate length-at-age differences between two Snake River white sturgeon (Acipenser transmontanus Richardson, 1836) populations in Idaho, USA
- Author
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Bates, P., primary, Chandler, J., additional, Lepla, K., additional, and Steinhorst, K., additional
- Published
- 2014
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7. Improving Glaucoma Patients' Quality of Life and Adherence With a Digital Health Application: [RETRACTED].
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Blanke L, Zinsmeister L, Schnell S, Steinhorst K, Lämmer R, and Michelson G
- Abstract
Prcies: Empowering glaucoma patients to access their individual glaucoma related health data by using a digital health application leads to a significant improvement in quality of life and adherence., Purpose: Evaluate the effectiveness of improvement of glaucoma associated quality of life and adherence in patients using a digital health application., Patients and Methods: A prospective randomized monocentric controlled study of 77 patients with primary open angle glaucoma. Patients were recruited at the University Hospital Erlangen. Patients in the intervention group tracked their intraocular pressure, symptoms and therapy using a digital application. Based on the collected data the SmartTonoTracker® gave patients simple statistics and basic recommendations for further treatment. An increasing score on the GlauQol-36 item questionnaire and the MMAS-8 score, conducted at baseline and follow-up by the intervention group, was considered successful. Statistical analysis was conducted using the unpaired t-test, paired t-test, Man-Whitney-U test, frequency analysis, frequency distribution and Pearson-correlation., Results: Significant difference in the patients´ glaucoma-associated quality of life between the intervention group (rate of improvement: 7.6%, P =0.047), and the control group (rate of improvement: 0.17%, P =0.047) was shown. Also, a significant difference in adherence between the intervention group, showing a 9.8% rate of improvement ( P =0.002), and the control group, showing a 3.8% rate of improvement ( P =0.002), was shown., Conclusion: Enabling patients to access individual health related glaucoma data by using a digital health application and supporting them with information on their disease led to an improvement in glaucoma-associated quality of life and adherence., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)
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- 2023
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8. Learning in the Single-Cell Organism Physarum polycephalum : Effect of Propofol.
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Kippenberger S, Pipa G, Steinhorst K, Zöller N, Kleemann J, Özistanbullu D, Kaufmann R, and Scheller B
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- Humans, Anesthetics, Intravenous pharmacology, Pain, Triglycerides pharmacology, Propofol pharmacology, Physarum polycephalum
- Abstract
Propofol belongs to a class of molecules that are known to block learning and memory in mammals, including rodents and humans. Interestingly, learning and memory are not tied to the presence of a nervous system. There are several lines of evidence indicating that single-celled organisms also have the capacity for learning and memory which may be considered as basal intelligence. Here, we introduce a new experimental model for testing the learning ability of Physarum polycephalum , a model organism frequently used to study single-celled "intelligence". In this study, the impact of propofol on Physarum 's "intelligence" was tested. The model consists of a labyrinth of subsequent bifurcations in which food (oat flakes soaked with coconut oil-derived medium chain triglycerides [MCT] and soybean oil-derived long chain triglycerides [LCT]) or propofol in MCT/LCT) is placed in one of each Y-branch. In this setting, it was tested whether Physarum memorized the rewarding branch. We saw that Physarum was a quick learner when capturing the first bifurcations of the maze; thereafter, the effect decreased, perhaps due to reaching a state of satiety. In contrast, when oat flakes were soaked with propofol, Physarum 's preference for oat flakes declined significantly. Several possible actions, including the blocking of gamma-aminobutyric acid (GABA) receptor signaling, are suggested to account for this behavior, many of which can be tested in our new model.
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- 2023
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9. Repurposing of the antibiotic nitroxoline for the treatment of mpox.
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Bojkova D, Zöller N, Tietgen M, Steinhorst K, Bechtel M, Rothenburger T, Kandler JD, Schneider J, Corman VM, Ciesek S, Rabenau HF, Wass MN, Kippenberger S, Göttig S, Michaelis M, and Cinatl J Jr
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- Humans, Anti-Bacterial Agents pharmacology, Antiviral Agents pharmacology, Cidofovir, Drug Repositioning, Mpox, Monkeypox drug therapy, Nitroquinolines pharmacology
- Abstract
The antiviral drugs tecovirimat, brincidofovir, and cidofovir are considered for mpox (monkeypox) treatment despite a lack of clinical evidence. Moreover, their use is affected by toxic side-effects (brincidofovir, cidofovir), limited availability (tecovirimat), and potentially by resistance formation. Hence, additional, readily available drugs are needed. Here, therapeutic concentrations of nitroxoline, a hydroxyquinoline antibiotic with a favourable safety profile in humans, inhibited the replication of 12 mpox virus isolates from the current outbreak in primary cultures of human keratinocytes and fibroblasts and a skin explant model by interference with host cell signalling. Tecovirimat, but not nitroxoline, treatment resulted in rapid resistance development. Nitroxoline remained effective against the tecovirimat-resistant strain and increased the anti-mpox virus activity of tecovirimat and brincidofovir. Moreover, nitroxoline inhibited bacterial and viral pathogens that are often co-transmitted with mpox. In conclusion, nitroxoline is a repurposing candidate for the treatment of mpox due to both antiviral and antimicrobial activity., (© 2023 The Authors. Journal of Medical Virology published by Wiley Periodicals LLC.)
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- 2023
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10. Drug Sensitivity of Currently Circulating Mpox Viruses.
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Bojkova D, Bechtel M, Rothenburger T, Steinhorst K, Zöller N, Kippenberger S, Schneider J, Corman VM, Uri H, Wass MN, Knecht G, Khaykin P, Wolf T, Ciesek S, Rabenau HF, Michaelis M, and Cinatl J Jr
- Subjects
- Humans, Drug Resistance, Viral physiology, Mpox, Monkeypox drug therapy, Mpox, Monkeypox physiopathology, Mpox, Monkeypox virology, Monkeypox virus drug effects, Monkeypox virus physiology, Antiviral Agents pharmacology
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- 2023
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11. Functional Downregulation of PD-L1 and PD-L2 by CpG and non-CpG Oligonucleotides in Melanoma Cells.
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Kleemann J, Steinhorst K, König V, Zöller N, Cinatl J Jr, Özistanbullu D, Kaufmann R, Meissner M, and Kippenberger S
- Abstract
The clinical application of immune checkpoint inhibitors represents a breakthrough progress in the treatment of metastasized melanoma and other tumor entities. In the present study, it was hypothesized that oligonucleotides (ODNs), known as modulators of the immune response, have an impact on the endogenous expression of checkpoint molecules, namely PD-L1 and PD-L2 (PD-L1/2). IFNγ-stimulated melanoma cells (A375, SK-Mel-28) were treated with different synthetically manufactured oligonucleotides which differed in sequence, length and backbone composition. It was found that a variety of different ODN sequences significantly suppressed PD-L1/2 expression. This effect was dependent on length and phosphorothioate (PTO) backbone. In particular, a sequence containing solely guanines (nCpG-6-PTO) was highly effective in downregulating PD-L1/2 at the protein, mRNA and promoter levels. Mechanistically, we gave evidence that ODNs with G-quartet-forming motifs suppress the interferon signaling axis (JAK/STAT/IRF1). Our findings identify a subset of ODNs as interesting pharmacological compounds that could expand the arsenal of targeted therapies to combat the immunological escape of tumor cells.
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- 2022
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12. Cardiac-specific deletion of voltage dependent anion channel 2 leads to dilated cardiomyopathy by altering calcium homeostasis.
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Shankar TS, Ramadurai DKA, Steinhorst K, Sommakia S, Badolia R, Thodou Krokidi A, Calder D, Navankasattusas S, Sander P, Kwon OS, Aravamudhan A, Ling J, Dendorfer A, Xie C, Kwon O, Cheng EHY, Whitehead KJ, Gudermann T, Richardson RS, Sachse FB, Schredelseker J, Spitzer KW, Chaudhuri D, and Drakos SG
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- Animals, Apoptosis, Calcium Signaling, Cardiomyopathy, Dilated mortality, Heart Failure metabolism, Mice, Mice, Knockout, Mitochondria metabolism, Mitochondrial Membranes metabolism, Myocardial Contraction, Myocytes, Cardiac metabolism, Transcriptome, Calcium metabolism, Cardiomyopathy, Dilated metabolism, Homeostasis, Voltage-Dependent Anion Channel 2 genetics, Voltage-Dependent Anion Channel 2 metabolism
- Abstract
Voltage dependent anion channel 2 (VDAC2) is an outer mitochondrial membrane porin known to play a significant role in apoptosis and calcium signaling. Abnormalities in calcium homeostasis often leads to electrical and contractile dysfunction and can cause dilated cardiomyopathy and heart failure. However, the specific role of VDAC2 in intracellular calcium dynamics and cardiac function is not well understood. To elucidate the role of VDAC2 in calcium homeostasis, we generated a cardiac ventricular myocyte-specific developmental deletion of Vdac2 in mice. Our results indicate that loss of VDAC2 in the myocardium causes severe impairment in excitation-contraction coupling by altering both intracellular and mitochondrial calcium signaling. We also observed adverse cardiac remodeling which progressed to severe cardiomyopathy and death. Reintroduction of VDAC2 in 6-week-old knock-out mice partially rescued the cardiomyopathy phenotype. Activation of VDAC2 by efsevin increased cardiac contractile force in a mouse model of pressure-overload induced heart failure. In conclusion, our findings demonstrate that VDAC2 plays a crucial role in cardiac function by influencing cellular calcium signaling. Through this unique role in cellular calcium dynamics and excitation-contraction coupling VDAC2 emerges as a plausible therapeutic target for heart failure., (© 2021. The Author(s).)
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- 2021
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13. Increased inducible nitric oxide synthase (iNOS) expression in human myocardial infarction.
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Wilmes V, Scheiper S, Roehr W, Niess C, Kippenberger S, Steinhorst K, Verhoff MA, and Kauferstein S
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- Adult, Aged, Cadaver, Female, Forensic Pathology, Gene Expression Regulation, Enzymologic, Humans, Male, Middle Aged, Oxidative Stress, RNA, Messenger genetics, Real-Time Polymerase Chain Reaction, Myocardial Infarction enzymology, Myocardium enzymology, Nitric Oxide Synthase Type II genetics
- Abstract
Increased inducible nitric oxide synthase (iNOS) expression has been reported in heart failure, cardiomyopathies, and arteriosclerosis. iNOS is expressed in the heart upon inflammatory stimuli and produces excessive amounts of nitric oxide (NO). The overproduction of NO is cytotoxic and involved in cardiovascular diseases. Furthermore, iNOS produces superoxide anion which proceeds with NO to the harmful oxidant peroxynitrite, causing oxidative stress in the heart. The aim of the study was to gain new insights into the role of iNOS in human myocardial infarction (MI) and its contribution to oxidative stress in the heart. Furthermore, we investigated the unaffected myocardium of the infarction hearts, to study if iNOS expression is increased, probably as an indicator for oxidative stress. Our results show a significant increase (p = 0.013) of the iNOS expression in the affected regions of MI hearts (n = 9) in comparison with healthy control hearts (n = 4). In the unaffected regions of MI hearts, an increase in the iNOS expression in some samples was found as well. Our study demonstrated the direct detection of iNOS mRNA in human myocardial tissue. The balance between beneficial and deleterious effects of iNOS may be particularly influenced by the presence or absence of concurrent oxidative stress.
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- 2020
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14. Collagen I Promotes Adipocytogenesis in Adipose-Derived Stem Cells In Vitro.
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Zöller N, Schreiner S, Petry L, Hoffmann S, Steinhorst K, Kleemann J, Jäger M, Kaufmann R, Meissner M, and Kippenberger S
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- Adipocytes drug effects, Adipocytes metabolism, Adiponectin genetics, Adiponectin metabolism, Cell Adhesion drug effects, Cells, Cultured, Humans, Integrin alpha2beta1 metabolism, Lipogenesis drug effects, RNA, Messenger genetics, RNA, Messenger metabolism, Receptors, Collagen metabolism, Stem Cells cytology, Stem Cells drug effects, Adipocytes cytology, Adipose Tissue cytology, Collagen Type I pharmacology, Stem Cells metabolism
- Abstract
A hallmark of ageing is the redistribution of body fat. Particularly, subcutaneous fat decreases paralleled by a decrease of skin collagen I are typical for age-related skin atrophy. In this paper, we hypothesize that collagen I may be a relevant molecule stimulating the differentiation of adipose-derived stem cells (ASCs) into adipocytes augmenting subcutaneous fat. In this context lipogenesis, adiponectin, and collagen I receptor expression were determined. Freshly isolated ASCs were characterized by stemness-associated surface markers by FACS analysis and then transdifferentiated into adipocytes by specific medium supplements. Lipogenesis was evaluated using Nile Red staining and documented by fluorescence microscopy or quantitatively measured by using a multiwell spectrofluorometer. Expression of adiponectin was measured by real-time RT-PCR and in cell-free supernatants by ELISA, and expression of collagen I receptors was observed by western blot analysis. It was found that supports coated with collagen I promote cell adhesion and lipogenesis of ASCs. Interestingly, a reverse correlation to adiponectin expression was observed. Moreover, we found upregulation of the collagen receptor, discoidin domain-containing receptor 2; receptors of the integrin family were absent or downregulated. These findings indicate that collagen I is able to modulate lipogenesis and adiponectin expression and therefore may contribute to metabolic dysfunctions associated with ageing.
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- 2019
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15. Fatty acid receptor GPR120: a novel marker for human melanoma.
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Kleemann J, Hrgovic I, Ter-Nedden J, Kleimann P, Steinhorst K, Härle K, Müller J, Kaufmann R, Meissner M, and Kippenberger S
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- Female, Humans, Immunohistochemistry, Male, Melanoma genetics, Melanoma pathology, Middle Aged, Receptors, G-Protein-Coupled genetics, Retrospective Studies, Skin Neoplasms genetics, Skin Neoplasms pathology, Melanoma metabolism, Receptors, G-Protein-Coupled metabolism, Skin Neoplasms metabolism
- Abstract
The correlation between ultraviolet radiation of the skin and melanoma incidence in humans is well established. Interestingly, epidemiologic data suggest also a correlation to an increased BMI pointing to metabolic trigger factors in melanoma pathogenesis. To substantiate this connection, we studied the expression of G-protein-coupled receptor 120 (GPR120), a receptor sensitive to unsaturated long-chain free fatty acids in melanoma tissues. One-hundred fourteen tissue sections histologically confirmed as nevi (n=32), primary melanoma (n=39), and melanoma metastasis (n=43) were immunohistochemically stained against GPR120. The staining was evaluated by three trained dermatopathologists and independently scored. Compared with nevi, primary melanoma and melanoma metastasis showed significantly higher levels of GPR120 staining. Only three out of 32 nevi showed strong GPR120 expression [median immunoreactivity-scoring system (IRS) score: 1, range: 0-10], whereas in primary melanomas 14 out of 39 were highly GPR120-positive (median IRS score: 7, range: 0-12) and in melanoma metastasis 27 out of 43 were highly GPR120-positive (median IRS score: 9, range: 0-12). GPR120 expression and tumor thickness (mm) show a statistically significant correlation in primary melanoma (P=0.011). Moreover, GPR120-positive staining was found throughout the epidermis and in sebaceous and sweat glands, which is yet not described. This study identified GPR120 as a novel marker for melanoma, indicating that melanoma cells are sensitive to free fatty acids. It is tempting to speculate that pharmacologically interfering with GPR120 signaling might improve melanoma therapy.
- Published
- 2018
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16. Activation of PKB/Akt and p44/42 by mechanical stretch utilizes desmosomal structures and the keratin filament.
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Kippenberger S, Kleemann J, Meissner M, Steinhorst K, Müller J, Zouboulis CC, Kaufmann R, and Zöller N
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- Calcium physiology, Cells, Cultured, Desmoglein 3 physiology, Enzyme Activation, Humans, Stress, Mechanical, Desmosomes physiology, Keratins physiology, Mitogen-Activated Protein Kinase 1 physiology, Mitogen-Activated Protein Kinase 3 physiology, Proto-Oncogene Proteins c-akt physiology
- Abstract
Background: Mechanical stress is an ubiquitous challenge of human cells with fundamental impact on cell physiology. Previous studies have shown that stretching promotes signalling cascades involved in proliferation and tissue enlargement., Objective: The present study is dedicated to learn more about cellular structures contributing to perception and signal transmission of cell stretch. In particular, we hypothesized that desmosmal contacts and the adjacent keratin filament build an intercellular matrix providing information about the mechanical load., Methods: Epidermal cells with different keratin equipment were seeded on flexible silicon dishes and stretched. As read out parameter the activation of PKB/Akt and p44/42 was monitored by Western blotting. Likewise desomosomal contacts were manipulated by depletion or addition of calcium. Moreover, desmoglein 3 and desmocollin 3 were blocked by either specific antibodies or siRNA., Results: It was found that the omission of calcium from the medium, a necessary cofactor for desmosomal cadherins, inhibited stretch mediated activation of PKB/Akt and p44/42. The relevance of desmosomes in this context was further substantiated by experiments using a desmoglein 3 blocking antibody (AK23) and siRNA against desmocollin 3. Moreover, disruption of the keratin filament by sodium orthovanadate also abrogates PKB/Akt and p44/42 activation in response to stretch. Likewise, KEB-7 keratinocytes harbouring a mutation in the keratin 14 gene and genetically modified keratinocytes devoid of any keratin show an altered signalling after stretch indicating the relevance of the keratin filament in this context., Conclusion: Besides their important role in cell architecture our results identify desmosomes and keratins as mechanosensing structures., (Copyright © 2017 Japanese Society for Investigative Dermatology. Published by Elsevier B.V. All rights reserved.)
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- 2018
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17. Sensitization of Melanoma Cells for Death Ligand TRAIL Is Based on Cell Cycle Arrest, ROS Production, and Activation of Proapoptotic Bcl-2 Proteins.
- Author
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Quast SA, Steinhorst K, Plötz M, and Eberle J
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- Blotting, Western, Cell Death genetics, Humans, Melanoma pathology, Membrane Potential, Mitochondrial physiology, RNA, Small Interfering metabolism, Sensitivity and Specificity, Transfection, Tumor Cells, Cultured, Apoptosis Regulatory Proteins metabolism, Cell Cycle Checkpoints physiology, Melanoma genetics, Proto-Oncogene Proteins c-bcl-2 metabolism, Reactive Oxygen Species metabolism, Receptors, TNF-Related Apoptosis-Inducing Ligand genetics
- Abstract
The death ligand TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) represents a promising strategy for melanoma due to significant expression of TRAIL receptor 1 in melanoma metastases and high TRAIL sensitivity through this receptor. However, prevalent and inducible resistance are limiting its clinical use. In previous work, we and others have described multiple strategies leading to TRAIL sensitization; however, the common principles of these strategies remained elusive. Here, we demonstrate in melanoma cell lines (TRAIL-sensitive, TRAIL-resistant, and TRAIL-selected cells with acquired resistance) that cell cycle arrest clearly correlates with enhanced TRAIL sensitivity. Cell cycle arrest was induced by high cell confluence, serum starvation, or cyclin-dependent kinase (CDK) 4/6 inhibition. Addressing the signaling pathways revealed disruption of mitochondrial membrane potential and production of reactive oxygen species (ROS) in response to antiproliferative conditions alone. Activation of the proapoptotic Bcl-2 protein Bax and inhibition of apoptosis by Bcl-2 overexpression or by the antioxidant N-acetyl cysteine underlined the critical involvement of mitochondrial apoptosis pathways and of ROS, respectively. Most pronounced was the upregulation of small proapoptotic Bcl-2 proteins (Puma and Bcl-xS). These data provide a general understanding on TRAIL sensitization as well as an alternative view on CDK inhibitors and may suggest selective targeting of melanoma cells by cell cycle inhibition and TRAIL.
- Published
- 2015
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18. Benchmark datasets for 3D MALDI- and DESI-imaging mass spectrometry.
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Oetjen J, Veselkov K, Watrous J, McKenzie JS, Becker M, Hauberg-Lotte L, Kobarg JH, Strittmatter N, Mróz AK, Hoffmann F, Trede D, Palmer A, Schiffler S, Steinhorst K, Aichler M, Goldin R, Guntinas-Lichius O, von Eggeling F, Thiele H, Maedler K, Walch A, Maass P, Dorrestein PC, Takats Z, and Alexandrov T
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- Animals, Benchmarking, Databases, Factual, Humans, Imaging, Three-Dimensional, Metabolomics, Mice, Reproducibility of Results, Spectrometry, Mass, Electrospray Ionization, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
- Abstract
Background: Three-dimensional (3D) imaging mass spectrometry (MS) is an analytical chemistry technique for the 3D molecular analysis of a tissue specimen, entire organ, or microbial colonies on an agar plate. 3D-imaging MS has unique advantages over existing 3D imaging techniques, offers novel perspectives for understanding the spatial organization of biological processes, and has growing potential to be introduced into routine use in both biology and medicine. Owing to the sheer quantity of data generated, the visualization, analysis, and interpretation of 3D imaging MS data remain a significant challenge. Bioinformatics research in this field is hampered by the lack of publicly available benchmark datasets needed to evaluate and compare algorithms., Findings: High-quality 3D imaging MS datasets from different biological systems at several labs were acquired, supplied with overview images and scripts demonstrating how to read them, and deposited into MetaboLights, an open repository for metabolomics data. 3D imaging MS data were collected from five samples using two types of 3D imaging MS. 3D matrix-assisted laser desorption/ionization imaging (MALDI) MS data were collected from murine pancreas, murine kidney, human oral squamous cell carcinoma, and interacting microbial colonies cultured in Petri dishes. 3D desorption electrospray ionization (DESI) imaging MS data were collected from a human colorectal adenocarcinoma., Conclusions: With the aim to stimulate computational research in the field of computational 3D imaging MS, selected high-quality 3D imaging MS datasets are provided that could be used by algorithm developers as benchmark datasets.
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- 2015
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19. Endothelial cells are highly heterogeneous at the level of cytokine-induced insulin resistance.
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Woth K, Prein C, Steinhorst K, Diehl S, Boehncke WH, and Buerger C
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- Brain cytology, Cell Line, Cell Line, Transformed, Female, Human Umbilical Vein Endothelial Cells, Humans, Inflammation, Microcirculation, Phenotype, Placenta cytology, Pregnancy, Signal Transduction, Skin cytology, Cytokines metabolism, Endothelial Cells cytology, Gene Expression Regulation, Insulin Resistance physiology, Psoriasis immunology
- Abstract
The endothelial wall plays a crucial role in various diseases as it serves as the barrier between circulatory system and organ tissue. Inflammation-driven insulin resistance and subsequent endothelial dysfunction represent a pathomechanism in cardiovascular diseases such as atherosclerosis and myocardial infarction. It was recently suggested that insulin resistance also contributes to the pathogenesis of psoriasis, a chronic inflammatory disease of the skin. However, it is not clear whether similar mechanisms at the endothelium contribute to the disease. In this study, we ask which endothelial cells are most suitable to address this question. We investigated the insulin response of four cell types (primary cells and cell lines) representing different vascular beds (micro- and macrovascular cells) in the presence of different pro-inflammatory cytokines. All four cell types used responded well to insulin; however, the ability to become resistant to insulin due to an inflammatory stimulus by cytokines involved in psoriasis (e.g. IL-1β, IL-12, IL-17, IL-23 and TNF-α) was very heterogeneous and could not be attributed to the differential expression of the cognate cytokine receptors. We conclude that this disparity is due to the different origins and properties of the endothelial cells used. Thus, endothelial cells should be carefully selected for the purpose of the respective study, particularly when it comes to analysing the pathogenesis of a disease and the search of new molecular targets for innovative therapies., (© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2013
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20. Methylprednisolone blocks autoantibody-induced tissue damage in experimental models of bullous pemphigoid and epidermolysis bullosa acquisita through inhibition of neutrophil activation.
- Author
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Hellberg L, Samavedam UKSRL, Holdorf K, Hänsel M, Recke A, Beckmann T, Steinhorst K, Boehncke WH, Kirchner T, Möckel N, Solbach W, Zillikens D, Schmidt E, Ludwig RJ, and Laskay T
- Subjects
- Adult, Animals, Antigen-Antibody Complex immunology, Butadienes pharmacology, Dermis cytology, Dermis immunology, Disease Models, Animal, Enzyme Inhibitors pharmacology, Epidermal Cells, Epidermis immunology, Epidermolysis Bullosa Acquisita immunology, Epidermolysis Bullosa Acquisita pathology, Glucocorticoids pharmacology, Humans, Imidazoles pharmacology, MAP Kinase Signaling System immunology, Mice, Mice, Inbred C57BL, Neutrophils cytology, Neutrophils immunology, Nitriles pharmacology, Pemphigoid, Bullous immunology, Pemphigoid, Bullous pathology, Pyridines pharmacology, Reactive Oxygen Species metabolism, Respiratory Burst drug effects, Respiratory Burst immunology, Autoantibodies immunology, Epidermolysis Bullosa Acquisita drug therapy, Methylprednisolone pharmacology, Neutrophils drug effects, Pemphigoid, Bullous drug therapy
- Abstract
Corticosteroids are regularly used to treat autoimmune diseases, such as bullous pemphigoid (BP). In BP, autoantibodies bind to type XVII collagen (COL17), located at the dermal-epidermal junction. A crucial role of neutrophils in experimental BP has been established. Specifically, reactive oxygen species and proteolytic granule enzymes mediate tissue injury. Therefore, we investigated the effects of methylprednisolone (MP) on neutrophils, which are likely to be affected by topical treatment. First, MP inhibited dermal-epidermal separation ex vivo in cryosections of the human skin induced by co-incubation of BP autoantibodies with neutrophils from healthy volunteers. Next, MP inhibited neutrophil activation in vitro induced by immune complexes (ICs) of COL17 and autoantibodies. This neutrophil activation was associated with phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2), p38 mitogen-activated protein kinase (MAPK), and Akt. In turn, inhibition of ERK1/2, p38 MAPK, or Akt phosphorylation inhibited neutrophil activation by IC in vitro and dermal-epidermal separation ex vivo. In addition, we observed an increase of p38 MAPK phosphorylation in dermal infiltrates of BP patients. Treatment of mice with either MP or inhibitors of p38-MAPK or ERK1/2 phosphorylation impaired induction of autoantibody- or irritant-induced neutrophil-dependent inflammation. We here identify the inhibition of Akt, ERK1/2, and p38 MAPK phosphorylation as molecular mechanisms to promote MP's therapeutic effects.
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- 2013
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21. Exploring three-dimensional matrix-assisted laser desorption/ionization imaging mass spectrometry data: three-dimensional spatial segmentation of mouse kidney.
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Trede D, Schiffler S, Becker M, Wirtz S, Steinhorst K, Strehlow J, Aichler M, Kobarg JH, Oetjen J, Dyatlov A, Heldmann S, Walch A, Thiele H, Maass P, and Alexandrov T
- Subjects
- Analytic Sample Preparation Methods, Animals, Mice, Imaging, Three-Dimensional methods, Kidney metabolism, Molecular Imaging methods, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization methods
- Abstract
Three-dimensional (3D) imaging has a significant impact on many challenges of life sciences. Three-dimensional matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) is an emerging label-free bioanalytical technique capturing the spatial distribution of hundreds of molecular compounds in 3D by providing a MALDI mass spectrum for each spatial point of a 3D sample. Currently, 3D MALDI-IMS cannot tap its full potential due to the lack efficient computational methods for constructing, processing, and visualizing large and complex 3D MALDI-IMS data. We present a new pipeline of efficient computational methods, which enables analysis and interpretation of a 3D MALDI-IMS data set. Construction of a MALDI-IMS data set was done according to the state-of-the-art protocols and involved sample preparation, spectra acquisition, spectra preprocessing, and registration of serial sections. For analysis and interpretation of 3D MALDI-IMS data, we applied the spatial segmentation approach which is well-accepted in analysis of two-dimensional (2D) MALDI-IMS data. In line with 2D data analysis, we used edge-preserving 3D image denoising prior to segmentation to reduce strong and chaotic spectrum-to-spectrum variation. For segmentation, we used an efficient clustering method, called bisecting k-means, which is optimized for hierarchical clustering of a large 3D MALDI-IMS data set. Using the proposed pipeline, we analyzed a central part of a mouse kidney using 33 serial sections of 3.5 μm thickness after the PAXgene tissue fixation and paraffin embedding. For each serial section, a 2D MALDI-IMS data set was acquired following the standard protocols with the high spatial resolution of 50 μm. Altogether, 512 495 mass spectra were acquired that corresponds to approximately 50 gigabytes of data. After registration of serial sections into a 3D data set, our computational pipeline allowed us to reveal the 3D kidney anatomical structure based on mass spectrometry data only. Finally, automated analysis discovered molecular masses colocalized with major anatomical regions. In the same way, the proposed pipeline can be used for analysis and interpretation of any 3D MALDI-IMS data set in particular of pathological cases.
- Published
- 2012
- Full Text
- View/download PDF
22. Determination of genetic sex in chinook salmon (Oncorhynchus tshawytscha) using the male-linked growth hormone pseudogene by real-time PCR.
- Author
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Nagler JJ, Cavileer T, Steinhorst K, and Devlin RH
- Subjects
- Alaska, Animals, DNA Primers, Fluorescent Dyes, Male, Washington, Growth Hormone genetics, Polymerase Chain Reaction methods, Pseudogenes genetics, Salmon genetics, Sex Determination Analysis methods
- Abstract
This study used a real-time quantitative polymerase chain reaction (qPCR) method based on the growth hormone pseudogene (GHp) in chinook salmon (Oncorhynchus tshawytscha) to determine genetic sex. The GHp is present as a single copy in the genome of the male chinook salmon but is absent in the female, providing a means of using this real-time qPCR method to discriminate genetic sex. Comparisons between genomic DNA samples from 2 geographically distinct populations of chinook salmon (Columbia River, Washington, and Yukon River, Alaska) showed, within each population examined, that the males were clearly differentiated from the females. There were no interpopulation differences between males or females. The advantages of this real-time qPCR method are that it is rapid, is amenable to high sample throughput, and provides an accurate numerical value that allows comparisons between samples by statistical methods.
- Published
- 2004
- Full Text
- View/download PDF
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