Publications by authors named "Schendel P"

Rheumatoid arthritis (RA) synovitis is dominated by monocytes/macrophages with inflammatory patterns resembling microbial stimulation. In search of triggers, we reduced the intestinal microbiome in 20 RA patients (open label study DRKS00014097) by bowel cleansing and 7-day fasting (≤250 kcal/day) and performed immune monitoring and microbiome sequencing. Patients with metabolic syndrome ( = 10) served as a non-inflammatory control group.

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Academic research plays a key role in identifying new drug targets, including understanding target biology and links between targets and disease states. To lead to new drugs, however, research must progress from purely academic exploration to the initiation of efforts to identify and test a drug candidate in clinical trials, which are typically conducted by the biopharma industry. This transition can be facilitated by a timely focus on target assessment aspects such as target-related safety issues, druggability and assayability, as well as the potential for target modulation to achieve differentiation from established therapies.

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Advances in microbiome research suggest involvement in chronic inflammatory diseases such as rheumatoid arthritis (RA). Searching for initial trigger(s) in RA, we compared transcriptome profiles of highly inflamed RA synovial tissue (RA-ST) and osteoarthritis (OA)-ST with 182 selected reference transcriptomes of defined cell types and their activation by exogenous (microbial) and endogenous inflammatory stimuli. Screening for dominant changes in RA-ST demonstrated activation of monocytes/macrophages with gene-patterns induced by bacterial and fungal triggers.

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Effective drug selection is the current challenge in rheumatoid arthritis (RA). Treatment failure may follow different pathomechanisms and therefore require investigation of molecularly defined subgroups. In this exploratory study, whole blood transcriptomes of 68 treatment-naïve early RA patients were analyzed before initiating MTX.

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The Ω phase of the liquid sodium α-Ω dynamo experiment at New Mexico Institute of Mining and Technology in cooperation with Los Alamos National Laboratory has demonstrated a high toroidal field B(ϕ) that is ≃8×B(r), where B(r) is the radial component of an applied poloidal magnetic field. This enhanced toroidal field is produced by the rotational shear in stable Couette flow within liquid sodium at a magnetic Reynolds number Rm≃120. Small turbulence in stable Taylor-Couette flow is caused by Ekman flow at the end walls, which causes an estimated turbulence energy fraction of (δv/v)(2)∼10(-3).

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This overview unit introduces general considerations and strategies for expressing proteins in E. coli. E.

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We report direct force measurements of the formation of a chemical bond. The experiments were performed using a low-temperature atomic force microscope, a silicon tip, and a silicon (111) 7x7 surface. The measured site-dependent attractive short-range force, which attains a maximum value of 2.

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Objective: To assess the relation between the course of rheumatoid arthritis (RA) during pregnancy or the onset of RA postpartum and DRB1, DQA1, and DQB1 incompatibilities between mother and child.

Methods: In 45 pregnancies of 33 RA patients the course of RA was related to the number of class II incompatibilities. Furthermore class II incompatibilities in 16 pregnancies followed by RA onset were compared with those in 87 control pregnancies.

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Dysregulation of neonatal myelopoiesis and thrombopoiesis predisposes the newborn to develop neutropenia and/or thrombocytopenia during states of increased demand. We have previously examined the effects of granulocyte colony-stimulating factor (G-CSF) alone or in combination with either stem cell factor (SCF) or interleukin-11 (IL-11) on in vivo neonatal rat hematopoiesis. In this study, we determined the effect of the triple combination of IL-11, SCF, and G-CSF on newborn rat hematopoiesis.

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IL-11, a new hematopoietic cytokine isolated from primate stromal cells (PU-34), has been shown to act synergistically with IL-3 to induce proliferation of early hematopoietic stem cells and induce in vitro CFU-MEG proliferation. We hypothesize that recombinant human (rh)IL-11 alone or in combination with granulocyte colony-stimulating factor (G-CSF) might modulate newborn in vivo granulopoiesis and thrombopoiesis. Newborn Sprague-Dawley rats were given 14 d of intraperitoneal rhIL-11 (0-250 micrograms/kg x 14 d), rhIL-11 (250 micrograms/kg) + rhG-CSF (5 micrograms/kg simultaneously x 14 d), rhIL-11 x 7 d followed by G-CSF x 7 d, G-CSF x 14 d, PBS/human serum albumin x 7 d followed by G-CSF x 7 d, or PBS/human serum albumin x 14 d.

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Purified recombinant human interleukin-11 (rhuIL-11) was assessed for its in vivo effects on the proliferation and differentiation of hematopoietic progenitors as well as its capacity to accelerate the recovery of a drug-suppressed hematopoietic system. Dosage and time sequence studies demonstrated that administration of IL-11 to normal mice resulted in increases in absolute numbers of femoral marrow and splenic myeloid (granulocyte-macrophage colony-forming unit [CFU-GM], burst-forming unit-erythroid [BFU-E], CFU-granulocyte, erythroid, macrophage, megakaryocyte) progenitor cells and in stimulation of these progenitors to a higher cell cycling rate. This was associated with increased numbers of circulating neutrophils.

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We have developed a versatile Escherichia coli expression system based on the use of E. coli thioredoxin (trxA) as a gene fusion partner. The broad utility of the system is illustrated by the production of a variety of mammalian cytokines and growth factors as thioredoxin fusion proteins.

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Interleukin 11 (IL-11) is a pleiotropic hematopoietic growth factor with stimulatory effects on multiple hematopoietic progenitor cells. An immortalized primate bone marrow stromal cell line was established to facilitate the analysis of interactions between hematopoietic progenitors and the microenvironment. This line was found to produce a novel growth factor that directed the proliferation of a murine plasmacytoma cell line.

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The availability of large quantities of highly purified recombinant interleukin 11 (rhuIL-11) has allowed us to investigate the effects of rhuIL-11 on sheep red blood cell (SRBC)-specific antibody responses in the murine system. The results showed that rhuIL-11 was effective in enhancing the generation of mouse spleen SRBC-specific plaque-forming cells (PFC) in the in vitro cell culture system in a dose-dependent manner. These effects of rhuIL-11 were abrogated completely by the addition of anti-rhuIL-11 antibody, but not by the addition of preimmunized rabbit serum.

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Treatment of rat hepatoma H-35 cells with purified human recombinant interleukin-11 (IL-11) resulted in the stimulated production of several major acute phase plasma proteins. The qualitative and quantitative changes were comparable to those mediated by IL-6 or leukemia inhibitor factor (LIF). Like IL-6, IL-11 acted synergistically with IL-1 on type 1 acute phase proteins.

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Granulocyte/macrophage-colony-stimulating factor (GM-CSF) is an effective growth factor for the blasts of acute myeloblastic leukemia (AML). Radioiodinated Chinese hamster ovary (CHO)-cell derived GM-CSF was prepared using Bolton-Hunter reagent to label free amino groups on the protein. Normal human neutrophils and the blast cells from AML patients were examined for binding.

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The association of interstitial nephritis, the most common renal lesion in Sjogren's syndrome, to the other manifestations of the disease is unclear. To begin to address this issue, the infiltrating cells in frozen kidney tissues from two patients with interstitial nephritis secondary to Sjogren's syndrome were characterized by indirect immunofluorescence. T cells predominated, the majority of which were helper/inducer cells (OKT4+).

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The genes for the two subunits of the formate dehydrogenase from Methanobacterium formicicum were cloned and their sequences determined. When expressed in Escherichia coli, two proteins were produced which had the appropriate mobility on an SDS gel for the two subunits of formate dehydrogenase and cross-reacted with antibodies raised to purified formate dehydrogenase. The genes for the two formate dehydrogenase subunits overlap by 1 base pair and are preceded by DNA sequences similar to both eubacterial and archaebacterial promoters and ribosome-binding sites.

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A mutation in the purB gene of E. coli K-12, isolated and partially characterized by Geiger and Speyer (1977), confers a temperature sensitive requirement for adenine and an antimutator phenotype at 30 degrees C. Several hypotheses about the mechanism of action of this mutation, named mud for mutation defective, were tested in the present work.

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Newly synthesized DNA is undermethylated in E. coli K-12. The amount of N6-methyl deoxyadenylic acid in labeled DNA varied from 0.

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The phenomenology of mutagenesis by N-methyl-N'-nitro-N-nitrosoguanidine and related alkylating agents is reviewed and a three-step model for the molecular events of mutagenesis is presented. The first step is the production of miscoding lesions, especially O6-methylguanine, and the induction and synthesis of methyltransferase. The second step is the generation of DNA sequences in which O6-methylguanine is paired with thymine.

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Extracts from Escherichia coli cells induced for the adaptive response have been prepared that are capable of repairing O6-methylguanine, O4-methylthymine, and the phosphotriesters produced on the DNA backbone by alkylating agents such as N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). The phosphotriesters are repaired by a methyltransferase distinct from the one that demethylates O6-methylguanine. We propose that this increased capacity to repair phosphotriesters accounts for much of the increased resistance to MNNG toxicity seen in cultures induced for the adaptive response.

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The mutagenic and toxic effects of a series of N-alkyl-N'-nitro-N-nitrosoguanidines were examined in Escherichia coli K-12. The role of nucleotide excision repair, the SOS response, and the adaptive response in both the reduction and the production of the biological effects of these chemicals was tested. The effects of ethyl-nitrosoguanidine are similar in nucleotide excision repair-proficient and -deficient strains, but both the mutagenicity and the toxicity of alkyl groups larger than two carbons are significantly reduced by the presence of this repair system.

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