20 results on '"Brach, M."'
Search Results
2. In Salah Gas CO2 storage JIP : surface gas and biological monitoring
- Author
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Jones, D.G., Lister, T.R., Smith, D.J., West, J.M., Coombs, P., Gadalia, A., Brach, M., Annunzialellis, A., Lombardi, S., Jones, D.G., Lister, T.R., Smith, D.J., West, J.M., Coombs, P., Gadalia, A., Brach, M., Annunzialellis, A., and Lombardi, S.
- Abstract
Surface gas and biological monitoring were carried out in 2009 at the In SalahGas project (Krechba, Algeria), where geological storage of CO2 has been underway since mid-2004. The CO2 is removed from produced natural gas and re-injected below the gas-water contact on the flanks of the reservoir. The biological work was the first such study undertaken at the site. Observations were made in: Uplifted areas around the three CO2 injection wells, around the KB-5 well where breakthrough of CO2 from the KB-502 injector had occurred, around the KB-4 well and in a background area away from CO2 injection and gas production. Near ground atmospheric measurements were made with a mobile open path laser system, with soil gas and flux measurements in support of these and of a botanical and microbiological survey. Longer term monitoring was initiated for radon and other gases using buried probes and activated charcoal integrative collectors. Laser measurements appeared to show only natural variations, but interference from the vehicle exhaust, windblown dust and rain was apparent. Modifications are needed to overcome these problems. Natural variation of atmospheric CO2 needs to be better constrained to identify anomalous values. Soil gas concentrations and fluxes were very low but slightly higher values over the KB-5 well could indicate low-level leakage. This is likely to be a legacy of breakthrough prior to the abandonment of the well. A variety of monocotyledonous and dicotyledenous plants was present, particularly in dry wadis or shallow depressions. The xerophytic flora and the microbial numbers were typical of such desert environments and the data provide baseline values since there were no indications of elevated CO2. There were analytical problems with the microbial activity determinations but it can be concluded that activities were low.
- Published
- 2011
3. Information seeking behavior and perceived health literacy of family caregivers of persons living with a chronic condition. The case of spinal cord injury in Switzerland.
- Author
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Diviani N, Zanini C, Jaks R, Brach M, Gemperli A, and Rubinelli S
- Subjects
- Adaptation, Psychological, Adolescent, Adult, Aged, Chronic Disease, Cost of Illness, Cross-Sectional Studies, Female, Humans, Male, Middle Aged, Spinal Cord Injuries psychology, Switzerland, Caregivers psychology, Family psychology, Health Literacy statistics & numerical data, Information Seeking Behavior
- Abstract
Objective: To examine the information seeking behavior and health literacy of caregivers of individuals living with spinal cord injury in Switzerland and their impact on the caregiving experience., Methods: Nationwide survey of family caregivers of people with spinal cord injury (N = 717). Caregivers aged 18+ who assisted with activities of daily living were included. Self-reported information seeking behavior, including topics, preferred sources, and health literacy were assessed and analyzed., Results: Health professionals were the most trusted source of information. Among information-seekers, higher health literacy levels were shown to be associated with lower subjective caregiver burden and, in turn, with higher caregivers' satisfaction with own health., Conclusion: Caregivers use information on different topics and coming from different sources. In order for information to improve the caregiving experience, however, caregivers need health literacy skills to make sense of it., Practice Implications: Building health literacy is a promising approach to support caregivers in their activities, reduce their subjective burden, and even to improve their health. Interventions should consider involving health professionals, as the most trusted source of information, and address both health-related and more practical issues., (Copyright © 2020 Elsevier B.V. All rights reserved.)
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- 2020
- Full Text
- View/download PDF
4. How healthcare professionals experience patient participation in designing healthcare services and products. A qualitative study in the field of spinal cord injury in Switzerland.
- Author
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Amann J, Brach M, and Rubinelli S
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- Adult, Feedback, Female, Humans, Internet, Interviews as Topic, Male, Middle Aged, Qualitative Research, Switzerland, Attitude of Health Personnel, Biomedical Technology, Diffusion of Innovation, Patient Participation, Spinal Cord Injuries rehabilitation
- Abstract
Objectives: This study explored healthcare professionals' accounts of patient participation, focusing particularly on aspects related to patients' contributions to the planning and design of healthcare services and products. It aimed to determine (1) how healthcare professionals experience patient participation, (2) what factors, in their view, may inhibit or promote it; and (3) through what channels they think it can take place., Methods: This study adopted a pragmatic epistemological approach. Data was collected through semi-structured interviews with healthcare professionals at four specialized centers for spinal cord injury in Switzerland., Results: Healthcare professionals who participated in this study were generally open to patient participation in the healthcare innovation process, highlighting several factors that may influence this process. Participants referred to three types of patient contributions that would usually emerge from informal exchange: (1) bringing in information unknown to staff; (2) reporting problems; and (3) providing concrete suggestions for improvement., Conclusion & Practice Implications: Healthcare professionals' positive view on and experiences with patient participation in the healthcare innovation process provide a fertile ground to further explore ways of fostering this new form of collaboration. Ultimately, it will be important to demonstrate its positive impact on both patients' as well as healthcare professionals' experiences., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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5. Designing interactivity on consumer health websites: PARAFORUM for spinal cord injury.
- Author
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Rubinelli S, Collm A, Glässel A, Diesner F, Kinast J, Stucki G, and Brach M
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- Chronic Disease, Delivery of Health Care, Health Behavior, Health Education methods, Humans, Community Participation, Consumer Health Information methods, Internet, Self Care, Spinal Cord Injuries, User-Computer Interface
- Abstract
Objective: This paper addresses the issue of interactivity on health consumer websites powered by health organizations, by presenting the design of PARAFORUM, an interactive website in the field of spinal cord injury (SCI)., Methods: The design of PARAFORUM is based on different streams of research in online health communication, web-based communities, open innovation communities and formative evaluation with stakeholders., Results: PARAFORUM implements a model of diversified interactivity based on individuals with SCI and their families, health professionals, and researchers sharing their expertise in SCI. In addition to traditional health professional/researcher-to-consumer and peer-to-peer interactions, through PARAFORUM consumers, health professionals and researchers can co-design ideas for the enhancement of practice and research on SCI., Conclusion: There is the need to reflect on the conceptualization and operationalization of interactivity on consumer health websites. Interactions between different users can make these websites important platforms for promoting self-management of chronic conditions, organizational innovation, and participatory research., Practice Implications: Interactivity on consumer health websites is a main resource for health communication. Health organizations are invited to build interactive websites, by considering, however, that the exploitation of interactivity require users' collaboration, processes and standards for managing content, creating and translating knowledge, and conducting internet-based studies., (Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.)
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- 2013
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6. Activation of Hodgkin cells via the CD30 receptor induces autocrine secretion of interleukin-6 engaging the NF-kappabeta transcription factor.
- Author
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Gruss HJ, Ulrich D, Dower SK, Herrmann F, and Brach MA
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- Antibodies, Monoclonal immunology, Antibodies, Monoclonal pharmacology, Base Sequence, Cytokines biosynthesis, Cytokines genetics, Genes, Reporter, Growth Hormone genetics, Humans, Interleukin-6 biosynthesis, Interleukin-6 genetics, Molecular Sequence Data, Promoter Regions, Genetic, Recombinant Fusion Proteins biosynthesis, Reed-Sternberg Cells metabolism, Transcription, Genetic, Transfection, Tumor Cells, Cultured, Gene Expression Regulation, Neoplastic, Hodgkin Disease pathology, Interleukin-6 metabolism, Ki-1 Antigen immunology, Lymphocyte Activation, NF-kappa B physiology, Neoplasm Proteins physiology, Reed-Sternberg Cells immunology, Signal Transduction physiology
- Abstract
The CD30 surface molecule is a recently identified member of the tumor necrosis factor/nerve growth factor receptor superfamily. Within the cytoplasmic signal transducing domain, CD30 shares no significant homology to other members of this family. Signaling events engaged via CD30 are still unknown. We here identify the NF-kappabeta transcription factor as a target of the CD30-induced signal pathway in Hodgkin's disease (HD) cells. Exposure of HD cells to CD30 ligand induces release of interleukin-6 (IL-6) that can be duplicated by cross-linking HD-cells to an agonistic anti-CD30 specific monoclonal antibody (alphaCD30), but not by cross-linking to an isotype-identical irrelevant monoclonal antibody. Cross-linking of HD cells to alphaCD30 leads to enhanced accumulation of IL-6 mRNA in a time-dependent fashion resulting from transcriptional activation of the IL-6 promoter. Transient transfection assays using a series of deleted IL-6 promoter constructs linked to the human growth hormone gene as a reporter gene furthermore indicate that transcriptional activation of the IL-6 promoter requires the presence of an intact NF-kappabeta binding site. In addition, introduction of an NF-kappabeta binding site appeared to be sufficient to confer inducibility of an heterologous promoter on activation of CD30 in HD cells. Cross-linking of CD30 promotes rapid and transient binding activity of nuclear proteins to the NF-kappabeta recognition site of the IL-6 promoter. Supershift experiments using a series of monoclonal antibodies recognizing distinct members of the NF-kappaBeta transcription factor family furthermore indicate that in CD30 cross-linked HD cells p50, p65/Rel-A, and Rel-B are present, whereas the c-rel protein is not.
- Published
- 1996
7. Transcript synthesis and surface expression of the interleukin-2 receptor (alpha-, beta-, and gamma-chain) by normal and malignant myeloid cells.
- Author
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Schumann RR, Nakarai T, Gruss HJ, Brach MA, von Arnim U, Kirschning C, Karawajew L, Ludwig WD, Renauld JC, Ritz J, and Herrmann F
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- Acute Disease, Antigens, CD biosynthesis, Antigens, CD chemistry, Antigens, CD genetics, Base Sequence, Bone Marrow pathology, Bone Marrow Cells, Cell Division drug effects, Gene Expression Regulation, Neoplastic, Hematopoietic Stem Cells pathology, Humans, Interleukin-2 pharmacology, Janus Kinase 3, Leukemia, Myeloid pathology, Molecular Sequence Data, Neoplasm Proteins biosynthesis, Neoplasm Proteins chemistry, Neoplasm Proteins genetics, Neoplastic Stem Cells metabolism, Phosphorylation drug effects, Polymerase Chain Reaction, Protein Processing, Post-Translational drug effects, Protein-Tyrosine Kinases metabolism, RNA, Messenger biosynthesis, Receptors, Interleukin biosynthesis, Receptors, Interleukin chemistry, Receptors, Interleukin genetics, Receptors, Interleukin physiology, Receptors, Interleukin-2 biosynthesis, Receptors, Interleukin-2 chemistry, Receptors, Interleukin-2 genetics, Receptors, Interleukin-4, Receptors, Interleukin-7, Receptors, Interleukin-9, Tumor Cells, Cultured, Gene Expression Regulation, Hematopoietic Stem Cells metabolism, Neoplasm Proteins physiology, Receptors, Interleukin-2 physiology, Transcription, Genetic
- Abstract
Expression of the interleukin-2 receptor alpha-(IL-2Ralpha-), IL-2Rbeta-, and the recently identified IL-2Rgamma-chain was examined on a wide range of cells of myeloid origin including neutrophils, monocytes, normal bone marrow-derived myeloid progenitors enriched for CD34+ cells, bone marrow blasts obtained from acute myelogenous leukemia (AML) patients, and permanent myeloid leukemia cell lines by reverse transcriptase-polymerase chain reaction and surface membrane analysis using receptor chain-specific monoclonal antibodies and flow cytometry. Expression of the p75 IL-2Rbeta- and the p64 IL-2Rgamma-chain was a common finding in most of the myeloid cell samples investigated, whereas IL-2Ralpha-chain was less frequently expressed. Although the high-affinity IL-2R form (ie, the alpha+, beta+, gamma+ IL-2R form) was detectable in a small minority of primary AML samples as well as the KG-1 cell line and IL-2 binding to these cells was sufficient to initiate signal transduction as evidenced by an increase in overall protein tyrosine phosphorylation and more specifically in tyrosine phosphorylation of the Janus kinase (JAK) 3, in none of these cell types did exposure to IL-2 affect cell growth kinetics. These results suggest that, in myeloid cells, the IL-2R may not stimulate mitogenic responses or that its components may be expressed in a combinational association with receptors for other cytokines and that IL-2Rgamma may play a regulatory role in normal and malignant myelopoiesis possibly independent from IL-2. Because recent studies by others have indicated that the IL-2Rgamma- chain may be shared by the IL-4R, the IL-7R, and most likely the IL-9R, expression of mRNA of these receptor types was also investigated in these cell samples. Surprisingly, in a substantial part of the myeloid lineage cells examined, an IL-2Rgamma+, IL-4R-, IL7R- configuration was noted that was, however, frequently associated with expression of IL-9R. Sharing of IL-9R/IL-2R components was furthermore suggested by inhibition of 125I-IL-2 binding to primary AML cells with excess of unlabeled IL-9.
- Published
- 1996
8. The NF-jun transcription factor in the hematopoietic response to mitogenic signals.
- Author
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Sott C, Herrmann F, and Brach MA
- Subjects
- Cell Division, Hematopoietic Stem Cells cytology, Humans, Hematopoietic Stem Cells drug effects, Mitogens pharmacology, Nuclear Proteins physiology, Proto-Oncogene Proteins c-jun physiology, Transcription Factors physiology
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- 1995
- Full Text
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9. Clinical applications of ribozymes.
- Author
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Kiehntopf M, Esquivel EL, Brach MA, and Herrmann F
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- Humans, Neoplasms drug therapy, RNA, Catalytic therapeutic use
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- 1995
- Full Text
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10. Transforming growth factor-beta relieves stem cell factor-induced proliferation of myelogenous leukemia cells through inhibition of binding of the transcription factor NF-jun.
- Author
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Sott C, Dorner B, Karawajew L, Herrmann F, and Brach MA
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- Binding Sites, Cell Division, DNA chemistry, DNA metabolism, Gene Expression, Genes, jun, Humans, Leukemia, Myeloid metabolism, Oligonucleotides, Antisense chemistry, Oligonucleotides, Antisense pharmacology, Promoter Regions, Genetic, Recombinant Proteins, Stem Cell Factor, Transcription, Genetic, Tumor Cells, Cultured, Hematopoietic Cell Growth Factors pharmacology, Leukemia, Myeloid pathology, Nuclear Proteins metabolism, Proto-Oncogene Proteins c-jun metabolism, Transforming Growth Factor beta pharmacology
- Abstract
Transforming growth factor-beta (TGF-beta) is a potent inhibitor of growth factor-stimulated hematopoiesis in normal and leukemic conditions. Using the factor-dependent myelogenous leukemia cell lines GF-D8 and Mo7, we show that TGF-beta interferes with stem cell factor (SCF)-induced proliferation by downmodulating c-jun gene expression. The ability of SCF to induce accumulation of c-jun transcripts was abolished when TGF-beta was present in culture. Transcriptional nuclear run-on assays indicated that TGF-beta relieved the capacity of SCF to enhance the transcriptional rate of the c-jun gene. Deletion analysis of the c-jun promoter furthermore showed that SCF was activating the c-jun promoter via the NF-jun transcription factor. Gel mobility shift assays showed that SCF increased the binding activity of NF-jun to its recognition site within 5 to 15 minutes. Binding activity peaked at 1 hour after exposure to SCF and declined to starting levels within 4 hours. The ability of SCF to enhance NF-jun binding activity was also dose-dependent in the range of 5 to 100 ng/mL. Exposure of GF-D8 and Mo7 cells to TGF-beta before the addition of SCF antagonized SCF-induced NF-jun binding. Moreover, whereas SCF was capable of functionally activating a heterologous promoter containing the NF-jun binding site, pretreatment of GF-D8 cells with TGF-beta abolished transcriptional activation of this heterologous promoter. These findings indicate that SCF-mediated activation of c-jun via NF-jun is crucial for the SCF-inducible proliferative response and is inhibited by TGF-beta. In additional experiments, the antisense technique was used. Treatment of GF-D8 and Mo7 cells with an antisense oligodeoxyribonucleotide directed against the translation initiation site of c-jun abolished the capacity of SCF to induce a proliferative response, whereas sense and nonsense oligomers had no effect. Taken together, our data indicate that the counteracting modulation of the binding activity of NF-jun by SCF and TGF-beta regulates the expression of the c-jun gene and thereby the proliferative state of the GF-D8 and Mo7 target.
- Published
- 1994
11. Post-transcriptional regulation of interleukin-6 gene expression in human keratinocytes by ultraviolet B radiation.
- Author
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de Vos S, Brach M, Budnik A, Grewe M, Herrmann F, and Krutmann J
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- Blotting, Northern, Cells, Cultured, Dose-Response Relationship, Drug, Enzyme-Linked Immunosorbent Assay, Gene Expression Regulation radiation effects, Humans, Interleukin-6 analysis, Interleukin-6 physiology, Keratinocytes chemistry, RNA Processing, Post-Transcriptional, RNA, Messenger analysis, RNA, Messenger genetics, RNA, Messenger metabolism, Time Factors, Interleukin-6 genetics, Keratinocytes cytology, Keratinocytes radiation effects, Transcription, Genetic radiation effects, Ultraviolet Rays
- Abstract
Exposure to increasing doses (290-315 nm) of ultraviolet (UV) B radiation is thought to profoundly affect human health. Studies on the biologic and molecular effects of UVB radiation on human skin are therefore of particular interest. There is experimental and clinical evidence to assume that UVB radiation-induced local and systemic inflammatory reactions might be mediated at least in part by UVB-induced keratinocyte-derived interleukin (IL)-6. Previously, a UVB-induced increase of steady-state levels of IL-6 mRNA was found to be a prerequisite for keratinocyte IL-6 production after UVB irradiation. The present study was aimed at addressing the question of whether in vitro UVB irradiation would increase IL-6 mRNA expression in long-term cultured, normal human keratinocytes via transcriptional or post-transcriptional mechanisms. UVB exposure (0-100 J/m2) of keratinocytes increased low baseline expression levels of IL-6 mRNA in a time- and dose-dependent manner. Using nuclear run-on assays, transcription rates of the IL-6 gene in nuclei isolated from UVB-irradiated cells were found to be essentially identical to those seen in unirradiated cells, indicating that UVB light did not lead to increased transcription of the IL-6 gene. To determine a possible post-transcriptional mechanism in UVB-induced IL-6 mRNA expression, the effects of UVB irradiation on IL-6 mRNA stability were examined. To this end irradiated and unirradiated keratinocytes were treated with actinomycin D and subjected to Northern blot analysis to calculate IL-6 mRNA half-life. As compared with unirradiated cells, IL-6 mRNA stability was increased significantly (three- to four-fold) in UVB-irradiated cells, suggesting that UVB radiation upregulates IL-6 mRNA levels in human keratinocytes by increasing the stability of IL-6 transcripts. This is the first report indicating that UVB radiation at a physiologically relevant dose may affect gene expression in human cells at a post-transcriptional level.
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- 1994
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12. Interleukin-3 and granulocyte-macrophage colony-stimulating factor induce activation of the MAPKAP kinase 2 resulting in in vitro serine phosphorylation of the small heat shock protein (Hsp 27).
- Author
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Ahlers A, Engel K, Sott C, Gaestel M, Herrmann F, and Brach MA
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- Benzoquinones, Cells, Cultured, Enzyme Activation drug effects, Humans, Interleukin-3 pharmacology, Intracellular Signaling Peptides and Proteins, Lactams, Macrocyclic, MAP Kinase Kinase 2, Phosphorylation, Quinones pharmacology, Rifabutin analogs & derivatives, Granulocyte-Macrophage Colony-Stimulating Factor pharmacology, Heat-Shock Proteins metabolism, Mitogen-Activated Protein Kinase Kinases, Protein Serine-Threonine Kinases metabolism, Protein-Tyrosine Kinases metabolism, Serine metabolism
- Abstract
Interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) have previously been reported to induce rapid phosphorylation of the mitogen-activated protein (MAP) kinase. However, little is known about signaling events initiated by both hematopoietins that occur downstream of the MAP kinase. MAP kinase has been shown to phosphorylate the AP-1 transcription factor and also to activate two kinases designated insulin-stimulated protein kinase-1 and MAP kinase-activated protein (MAP-KAP) kinase 2. We show here that IL-3 and GM-CSF induce MAPKAP kinase 2 activity in the human megakaryoblastic leukemia cell line MO7 and phosphorylate the human small heat shock protein Hsp 27 on serine residues in vitro. GM-CSF also induced Hsp 27 phosphorylation in neutrophils in a range similar to that observed in MO7 cells, suggesting that MAPKAP kinase 2-mediated Hsp 27 activation occurs independently of proliferation. Hsp 27 phosphorylation was dose-dependent, occurred as early as 5 minutes after factor exposure, and was inhibited by the tyrosine kinase inhibitors genistein and herbimycin A. Furthermore, the protein phosphatase A2 abolished IL-3- and GM-CSF-induced serine phosphorylation of Hsp 27. Taken together, our findings indicate that tyrosine phosphorylation of MAP kinase is a prerequisite for serine phosphorylation of Hsp 27, which is mediated by MAPKAP kinase 2. Hsp 27 has shown activation-dependent translocation from the cytosolic to the nuclear region and has been linked to the cellular stress response. However, its precise function is largely unknown. Our data identify Hsp 27 as a target of the IL-3/GM-CSF stimulation pathway that involves MAP kinase and MAPKAP kinase 2. In addition, our results indicate that Hsp 27 may be target of phosphorylation events not only in the stress response but also in unstressed cells responding to cytokine stimulation.
- Published
- 1994
13. Prolongation of survival of human polymorphonuclear neutrophils by granulocyte-macrophage colony-stimulating factor is caused by inhibition of programmed cell death.
- Author
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Brach MA, deVos S, Gruss HJ, and Herrmann F
- Subjects
- Complement C5a pharmacology, Cycloheximide pharmacology, Dactinomycin pharmacology, Female, Granulocyte Colony-Stimulating Factor pharmacology, Humans, Interleukin-3 pharmacology, Interleukin-4 pharmacology, Interleukin-6 pharmacology, Interleukin-8 pharmacology, Kinetics, Male, N-Formylmethionine Leucyl-Phenylalanine pharmacology, Neutrophils drug effects, Recombinant Proteins pharmacology, Time Factors, Transforming Growth Factor beta pharmacology, Apoptosis drug effects, Cell Survival drug effects, Cytokines pharmacology, Granulocyte-Macrophage Colony-Stimulating Factor pharmacology, Neutrophils cytology
- Abstract
In the absence of appropriate stimuli, polymorphonuclear neutrophils (PMN) undergo programmed cell death (PCD), also termed apoptosis. We show that granulocyte-macrophage colony-stimulating factor (GM-CSF), but not the chemotactic factors formyl-methionyl-leucyl-phenylalanine (FMLP), recombinant human (rh) C5a, transforming growth factor (TGF)-beta, and interleukin-8 (IL-8), or other cytokines including IL-3, IL-4, IL-6, and G-CSF, maintains viability of PMN in culture by preventing these cells from undergoing PCD. Prevention from PCD by GM-CSF was associated with induction of RNA and protein synthesis in PMN. Inhibition of RNA and protein synthesis by actinomycin-D and cycloheximide impeded the protection of apoptosis by GM-CSF. Similarly, neutralization of GM-CSF biologic activity by a specific antiserum abrogated GM-CSF-mediated inhibition of PCD.
- Published
- 1992
14. Involvement of nuclear factor-kappa B in induction of the interleukin-6 gene by leukemia inhibitory factor.
- Author
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Gruss HJ, Brach MA, and Herrmann F
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- Binding Sites, Blotting, Northern, Cells, Cultured, DNA metabolism, Growth Hormone genetics, Humans, Interleukin-6 biosynthesis, Kinetics, Leukemia Inhibitory Factor, Promoter Regions, Genetic, Recombinant Proteins pharmacology, Transcription Factors metabolism, Transcription, Genetic, Gene Expression, Growth Inhibitors pharmacology, Interleukin-6 genetics, Lymphokines pharmacology, NF-kappa B metabolism, Phagocytes metabolism
- Abstract
Recent studies have indicated that the leukemia inhibitory factor (LIF) induces secretion of interleukin-6 (IL-6) in myeloid cells. We here show that synthesis of IL-6 by human mononuclear phagocytes exposed to recombinant human (rh) LIF is preceded by an increase of IL-6 transcript levels as a result of transcriptional activation of the IL-6 gene. Analysis of deleted fragments of the IL-6 promoter indicated that transcriptional activation of the IL-6 promoter was associated with enhanced binding activity of the transcription factor nuclear factor (NF)-kappa B. Binding of activation protein (AP)-1 and NF-IL-6, also known to transcriptionally activate the IL-6 promoter, was not inducible by LIF. Furthermore, introduction of the NF-kappa B sequence into a heterologous promoter construct, but not of AP-1- and NF-IL-6-binding sequences, conferred inducibility by LIF to this promoter. Deletion of the NF-kappa B binding site in the IL-6 promoter was associated with loss of inducibility by LIF, lending further support for the notion that the NF-kappa B binding site is crucial for LIF-mediated induction of the IL-6 promoter. Taken together, our results show that rhLIF induces IL-6 gene expression in mononuclear phagocytes through transcriptional gene activation involving NF-kappa B.
- Published
- 1992
15. High concentrations of the interleukin-1 receptor antagonist in serum of patients with Hodgkin's disease.
- Author
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Gruss HJ, Dölken G, Brach MA, Mertelsmann R, and Herrmann F
- Subjects
- Humans, Hodgkin Disease blood, Interleukin-1 blood
- Published
- 1992
- Full Text
- View/download PDF
16. Functional expression of c-kit by acute myelogenous leukemia blasts is enhanced by tumor necrosis factor-alpha through posttranscriptional mRNA stabilization by a labile protein.
- Author
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Brach MA, Bühring HJ, Gruss HJ, Ashman LK, Ludwig WD, Mertelsmann RH, and Herrmann F
- Subjects
- Cycloheximide pharmacology, Hematopoietic Cell Growth Factors pharmacology, Humans, Proto-Oncogene Mas, Proto-Oncogene Proteins c-kit, Receptors, Cell Surface analysis, Stem Cell Factor, Tumor Cells, Cultured, Gene Expression Regulation drug effects, Hematopoietic Cell Growth Factors genetics, Leukemia, Myeloid, Acute genetics, Proto-Oncogene Proteins genetics, Proto-Oncogenes, RNA, Messenger analysis, Tumor Necrosis Factor-alpha pharmacology
- Abstract
The c-kit proto-oncogene encodes a transmembrane glycoprotein identical to the receptor for the recently cloned stem cell factor (SCF). The present study examines constitutive synthesis of transcripts in primary acute myelogenous leukemia (AML) blasts and the effects of recombinant human tumor necrosis factor (TNF)-alpha on c-kit mRNA expression in these cells. The c-kit transcripts were detectable at low levels in 10 of 10 different AML samples investigated. TNF treatment of AML cells was associated with enhanced c-kit mRNA expression in all specimens. Nuclear run-on transcription assays indicated that the c-kit gene was transcriptionally active in all leukemias examined and the rate of transcription was unaffected by exposure to TNF, suggesting posttranscriptional control mechanisms of c-kit mRNA accumulation. In the absence of TNF, the half-life of c-kit transcripts was 2 to 3 hours, while in TNF-treated AML cells, c-kit half-life was found to be 5 to 9 hours. Inhibition of protein synthesis reduced TNF-induced c-kit mRNA expression by Northern blot analysis, but did not affect the rate of c-kit gene transcription. In the presence of inhibition of protein synthesis, the half-life of c-kit transcripts in TNF-induced leukemia cells decreased to 2 to 4 hours. These findings indicate that levels of c-kit mRNA are controlled by a labile protein that is involved in TNF-mediated stabilization of c-kit transcripts. The effects of TNF-alpha also extended to the protein level in that TNF-alpha treatment of primary AMLs was associated with enhanced surface expression of the SCF receptor by some of these cells. While exogenous SCF induced clonogenic growth of all primary AML samples investigated, TNF-alpha failed to stimulate leukemic cells to proliferate. However, the combination of SCF and TNF-alpha resulted in synergistic growth stimulation in seven of nine different AML specimens investigated. The finding of transmodulation of the SCF receptor through posttranscriptional modifications might further contribute to our understanding of the synergistic interplay of TNF-alpha and SCF.
- Published
- 1992
17. Interleukin-1 beta (IL-1 beta) expression in human blood mononuclear phagocytes is differentially regulated by granulocyte-macrophage colony-stimulating factor (GM-CSF), M-CSF, and IL-3.
- Author
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Oster W, Brach MA, Gruss HJ, Mertelsmann R, and Herrmann F
- Subjects
- Base Sequence, Blotting, Northern, Half-Life, Humans, Molecular Sequence Data, NF-kappa B metabolism, RNA, Messenger biosynthesis, RNA, Messenger metabolism, Recombinant Proteins pharmacology, Transcription, Genetic, Gene Expression Regulation, Granulocyte-Macrophage Colony-Stimulating Factor pharmacology, Interleukin-1 genetics, Interleukin-3 pharmacology, Macrophage Colony-Stimulating Factor pharmacology, Phagocytes metabolism
- Abstract
In this report we show that recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) and rh macrophage (M)-CSF induce accumulation of interleukin-1 beta (IL-1 beta) mRNA in blood-derived mononuclear phagocytes (MNP). GM-CSF and M-CSF treatment of MNP is also associated with IL-1 beta secretion. Regulation of GM- and M-CSF-induced IL-1 beta mRNA expression involves transcriptional and posttranscriptional mechanisms. However, the action of IL-3 on synthesis of IL-1 beta mRNA differs from that of other CSFs: While GM-CSF and M-CSF induce binding activity of the nuclear factor (NF) kappa B, IL-3 treatment of MNP has no profound effect on NF kappa B binding to DNA. Moreover, IL-3 decreases the transcription rate of the IL-1 beta gene and has only little effect on stability of IL-1 beta mRNA, which is increased by GM- and M-CSF. However, IL-3 enhances M-CSF-induced accumulation of IL-1 beta mRNA by unknown posttranscriptional means that may relate to an increased expression of M-CSF receptor (ie, c-fms) mRNA, detectable in mononuclear phagocytes on exposure to IL-3.
- Published
- 1992
18. Activation of the AP-1 transcription factor by arabinofuranosylcytosine in myeloid leukemia cells.
- Author
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Brach MA, Herrmann F, and Kufe DW
- Subjects
- Base Sequence, Enhancer Elements, Genetic, Gene Expression Regulation, Humans, Microbial Collagenase genetics, Molecular Sequence Data, Oligonucleotides chemistry, Regulatory Sequences, Nucleic Acid, Transcription, Genetic, Tumor Cells, Cultured, Cytarabine pharmacology, Leukemia, Myeloid genetics, Promoter Regions, Genetic, Proto-Oncogene Proteins c-jun genetics, Proto-Oncogene Proteins c-jun physiology
- Abstract
Previous studies have shown that 1-beta-D-arabinofuranosylcytosine (ara-C) induces transcription of the c-jun immediate early response gene in human myeloid leukemia cells. The present work has examined the mechanisms responsible for this effect. Deleted forms of the c-jun promoter were linked to the chloramphenicol acetyltransferase (CAT) gene and transfected into KG-1 cells. The results demonstrate that ara-C-induced c-jun transcription is mediated by an element between positions -74 and -20 upstream to the start site. Electrophoretic mobility shift assays with the fragment f(-74/-20) showed an increase in binding with nuclear proteins from ara-C-treated cells as compared with untreated cells. Competition with an oligonucleotide containing the AP-1 consensus sequence indicated that ara-C stimulates binding of nuclear proteins at the AP-1 site in the c-jun promoter. These findings were confirmed in other gel shift studies with the collagenase enhancer AP-1 consensus sequence and with a DNA fragment containing an altered AP-1 site. The binding of JUN/AP-1 was maximal at 1 hour of ara-C treatment and decreased to baseline levels at 12 hours. The finding that ara-C induces AP-1 binding in the absence of protein synthesis indicated that this agent activates already synthesized JUN/AP-1. To confirm these findings, the AP-1 consensus sequence was introduced 5' to the heterologous SV40 promoter. The results show that AP-1 enhances SV40 promoter activity in ara-C-treated cells. Taken together, these findings indicate that: (1) enhancement of JUN/AP-1 activity in ara-C-treated cells involves a posttranslational modification of JUN/AP-1; and (2) binding of activated JUN/AP-1 to the AP-1 site in the c-jun promoter confers ara-C inducibility of this gene.
- Published
- 1992
19. Interleukin-4 inhibits growth of multiple myelomas by suppressing interleukin-6 expression.
- Author
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Herrmann F, Andreeff M, Gruss HJ, Brach MA, Lübbert M, and Mertelsmann R
- Subjects
- Base Sequence, Humans, Molecular Sequence Data, Tumor Cells, Cultured drug effects, Interleukin-4 pharmacology, Interleukin-6 physiology, Multiple Myeloma pathology
- Abstract
Unfractionated bone marrow (BM) cells obtained from patients with multiple myeloma (MM) exhibit high levels of interleukin (IL)-6. Secretion of IL-6 by these cells as well as spontaneous plasma cell proliferation can be abrogated by neutralizing anti-IL-6 monoclonal antibody (MoAb). Treatment of BM cells with recombinant human (rh)IL-4 at doses of 50 to 250 U/mL blocked endogenous IL-6 synthesis in a dose-dependent fashion and was associated with significant reduction of plasma cell growth that could be reversed by exogenous rhIL-6. Enrichment of BM cells from MM patients for plasma cells and adherent cells and analysis of IL-6 mRNA in these subpopulations by means of quantitative polymerase chain reaction (PCR) showed that adherent BM cells accounted for most of the synthesis of IL-6 transcripts, whereas plasma cells displayed negligible levels of IL-6 mRNA only. These results suggest therapeutic evaluation of rhIL-4 in patients with plasma cell neoplasms.
- Published
- 1991
20. Interleukin-6 (IL-6) is an intermediate in IL-1-induced proliferation of leukemic human megakaryoblasts.
- Author
-
Brach MA, Löwenberg B, Mantovani L, Schwulera U, Mertelsmann R, and Herrmann F
- Subjects
- Antibodies, Monoclonal, Cell Transformation, Neoplastic drug effects, Cell Transformation, Neoplastic pathology, Cells, Cultured, DNA biosynthesis, Granulocyte Colony-Stimulating Factor genetics, Granulocyte Colony-Stimulating Factor immunology, Granulocyte Colony-Stimulating Factor physiology, Granulocyte-Macrophage Colony-Stimulating Factor genetics, Granulocyte-Macrophage Colony-Stimulating Factor immunology, Granulocyte-Macrophage Colony-Stimulating Factor physiology, Humans, Interleukin-1 metabolism, Interleukin-6 genetics, Leukemia, Megakaryoblastic, Acute metabolism, Macrophage Colony-Stimulating Factor genetics, Macrophage Colony-Stimulating Factor metabolism, Macrophage Colony-Stimulating Factor physiology, Megakaryocytes metabolism, Megakaryocytes ultrastructure, RNA metabolism, Receptors, Immunologic genetics, Receptors, Immunologic metabolism, Receptors, Interleukin-6, Recombinant Proteins metabolism, Recombinant Proteins pharmacology, Thymidine metabolism, Transcription, Genetic drug effects, Tritium, Interleukin-1 pharmacology, Interleukin-6 metabolism, Leukemia, Megakaryoblastic, Acute pathology, Megakaryocytes pathology
- Abstract
We have examined the in vitro effects of recombinant human (rh) interleukin-1 (IL-1) on the growth of purified megakaryoblasts obtained from patients with acute megakaryoblastic leukemia. We demonstrate that both IL-1 alpha and IL-1 beta treatment of these cells led to stimulation of DNA synthesis (as shown by increase of 3H-thymidine incorporation up to 35-fold) and also resulted in colony formation of leukemic megakaryoblasts. However, the stimulatory effect of IL-1 was dependent on endogenous production of IL-6, because addition of neutralizing monoclonal antibody (MoAb) to IL-6 abrogated the stimulatory activity of IL-1. In contrast, neutralizing MoAbs to granulocyte (G)-colony stimulating factor (CSF), granulocyte-macrophage (GM)-CSF, and macrophage (M)-CSF failed to counteract the growth-enhancing effects of IL-1. Leukemic megakaryoblasts accumulated IL-6 mRNA and released IL-6 protein into their culture supernatant when exposed to rh IL-1 but failed to disclose transcripts for G-, GM-, and M-CSF under these conditions. Analysis of IL-6 receptor (IL-6R) transcript levels demonstrated that megakaryoblasts constitutively expressed IL-6R mRNA and that these transcripts are down-regulated to undetectable levels upon exposure to IL-1 and IL-6. Increase of 3H-thymidine incorporation by megakaryoblasts could be duplicated by exogenous IL-6 that could be blocked by neutralizing MoAb to IL-6. In conclusion, our results suggest that leukemic megakaryoblasts could produce and secrete IL-6, and express IL-6R, and that the growth-enhancing effect of IL-1 on these cells is indirect, via production of IL-6 by leukemic cells.
- Published
- 1990
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