801
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Fischer R, Ostendorf B, Richter J, Schneider M. [Hypovolemic shock associated with generalized edema: paroxysmal non-hereditary angioedema (Clarkson syndrome)]. Dtsch Med Wochenschr 2000; 125:427-8. [PMID: 10812367 DOI: 10.1055/s-2007-1024234] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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802
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Schindler TH, Magosaki N, Jeserich M, Krause T, Fischer R, Moser E, Nitzsche E, Just H, Solzbach U. [New developments in diagnosis of coronary heart disease--3D fusion image]. ZEITSCHRIFT FUR KARDIOLOGIE 2000; 89:338-48. [PMID: 10868009 DOI: 10.1007/s003920050494] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The interpretation of three-dimensional (3D) structures of the coronary tree and the myocardium by a clinician demands a subjective visual integration of two-dimensional (2D) images of cardiac diagnostic procedures like coronary angiography and myocardial scintigraphy. Although in the conventional analysis of 2D display scintigraphic myocardial perfusion segments are arbitrarily assigned to three major coronary artery systems, the standard myocardial perfusion distribution territories correspond with the individual pathologic-anatomic coronary tree in only 50-60% of the patients. Hence, the mental integration of both 2D images of coronary angiography and myocardial scintigraphy does not necessarily allow an accurate assignment of particular myocardial perfusion regions to the corresponding vessels. For an objective assignment of each vessel segment of the coronary tree to the corresponding myocardial regions, we have developed a 3D "fusion image" technique and applied it to patients with coronary artery disease. Cause-and-effect relationships may be more obvious with 3D data fusion and may enable an easier comparison of anatomy and physiology. Preliminary results demonstrate that our newly developed 3D fusion image is useful for accurate assignment of coronary vessel segments to the corresponding myocardial perfusion regions and suggest that it may allow the clinician a comprehensive and accurate assessment of the patient's myocardial status.
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803
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Fischer R, Hoffmann K, Schillberg S, Emans N. Antibody production by molecular farming in plants. J BIOL REG HOMEOS AG 2000; 14:83-92. [PMID: 10841283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
"Molecular farming" is the production of pharmaceutical proteins in transgenic plants and has great potential for the production of therapeutic anti-cancer antibodies and recombinant therapeutic proteins. Plants make fully functional recombinant human or animal antibodies. Cultivating transgenic plants on an agricultural scale will produce almost unlimited supplies of recombinant proteins for uses in medicine. Combinatorial library technology is a key tool for the generation and optimisation of therapeutic antibodies ahead of their expression in plants. Optimised antibody expression can be rapidly verified using transient expression assays in plants before creation of transgenic suspension cells or plant lines. Subcellular targeting signals that increase expression levels and optimise protein stability can be identified and exploited using transient expression to create high expresser plant lines. When high expresser lines have been selected, the final step is the development of efficient purification methods to retrieve functional antibody. Antibody production on an industrial scale is then possible using plant suspension cell culture in fermenters, or by the propagation of stably transformed plant lines in the field. Recombinant proteins can be produced either in whole plants or in seeds and tubers, which can be used for the long-term storage of both the protein and its production system. The review will discuss these developments and how we are moving toward the molecular farming of therapeutic antibodies becoming an economic and clinical reality.
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804
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Dürken M, Herrnring C, Finckh B, Nagel S, Nielsen P, Fischer R, Berger HM, Moison RM, Pichlmeier U, Kohlschütter B, Zander AR, Kohlschütter A. Impaired plasma antioxidative defense and increased nontransferrin-bound iron during high-dose chemotherapy and radiochemotherapy preceding bone marrow transplantation. Free Radic Biol Med 2000; 28:887-94. [PMID: 10802219 DOI: 10.1016/s0891-5849(00)00174-x] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
To analyze the effects of radiochemotherapy on the pro-oxidative/antioxidative balance in plasma, we measured the total radical antioxidant parameter of plasma (TRAP) and single plasma antioxidants (uric acid, sulfhydryl groups, alpha-tocopherol, ubiquinone-10/total coenzyme-Q10 ratio, ascorbate, and bilirubin) every 12 h during high-dose chemotherapy and radiochemotherapy preceding bone marrow transplantation (BMT). Nontransferrin-bound iron (NTBI) was monitored as a potential pro-oxidant. Plasma levels of polyunsaturated fatty acids (PUFA) were measured as substrates, and thiobarbituric acid-reactive substances (TBARS) were measured as products of lipid peroxidation. Allantoin was analyzed as the product of uric acid oxidation. Patients receiving busulfan, VP-16, and cyclophosphamide (BU/VP/CY) (n = 8) were compared with those receiving total body irradiation in addition to VP-16 and cyclophosphamide (TBI/VP/CY) (n = 8). TRAP values were within the normal range before therapy and decreased after BU/VP/CY by 37% (p <. 02) and after TBI/VP/CY by 39% (p <.02). During TBI and after VP-16, a temporary increase in TRAP values occurred, which was not related to changes in individual antioxidants. In vitro experiments confirmed that VP-16 had an antioxidative effect. The concentration of uric acid declined in both groups and correlated with TRAP (BU/VP/CY: r =.80, p <.001; TBI/VP/CY: r =.84, p <.001). Levels of NTBI, which is normally not found in plasma, increased rapidly during conditioning therapy (p <.02 in both groups) and correlated inversely with TRAP (weighted intraindividual Spearman rank correlation coefficient for both groups: NTBI and TRAP: r = -.59, p <.001) and PUFA (in the radiochemotherapy group: r = -.67, p <.001). Whereas PUFA declined (p <.02 in both groups), TBARS increased (p <. 05 in both groups). Furthermore, an increase of allantoin and ubiquinone-10/total coenzyme-Q10 ratio in the BU/VP/CY group was found (allantoin: p <.02; ubiquinone-10/total coenzyme-Q10 ratio: p <.05). Antioxidants only partially recovered to baseline values until day 14 after BMT. Our findings indicate oxidative stress after high-dose radiochemotherapy and suggest a contribution of NTBI therein.
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805
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Hartmann G, Tschöp M, Fischer R, Bidlingmaier C, Riepl R, Tschöp K, Hautmann H, Endres S, Toepfer M. High altitude increases circulating interleukin-6, interleukin-1 receptor antagonist and C-reactive protein. Cytokine 2000; 12:246-52. [PMID: 10704252 DOI: 10.1006/cyto.1999.0533] [Citation(s) in RCA: 301] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Hypoxic pulmonary vasoconstriction is associated with but may not be sufficient for the development of high-altitude pulmonary oedema (HAPO). Hypoxia is known to induce an inflammatory response in immune cells and endothelial cells. It has been speculated that hypoxia-induced inflammatory cytokines at high altitude may contribute to the development of HAPO by causing capillary leakage in the lung. We were interested if such an inflammatory response, possibly involved in a later development of HAPO, is detectable at high altitude in individuals without HAPO. We examined the plasma levels of interleukin 6 (IL-6), interleukin 1 receptor antagonist (IL-1ra) and C-reactive protein (CRP) in two independent studies: study A, Jungfraujoch, Switzerland, three overnight stays at 3458 m, n=12; study B: Capanna Regina Margherita, Italy, 3 overnight stays at 3647 m and one overnight stay at 4559 m, n=10. In both studies, probands showed symptoms of acute mountain sickness but no signs of HAPO. At the Jungfraujoch, IL-6 increased from 0.1+/-0.03 pg/ml to 2. 0+/-0.5 pg/ml (day 2, P=0.03), IL-1ra from 101+/-21 to 284+/-73 pg/ml (day 2, P=0.01), and CRP from 1.0+/-0.4 to 5.8+/-1.5 micrograms/ml (day 4, P=0.01). At the Capanna Margherita, IL-6 increased from 0. 5+/-0.2 pg/ml to 2.0+/-0.8 pg/ml (P=0.02), IL-1ra from 118+/-25 to 213+/-28 pg/ml (P=0.02), and CRP from 0.4+/-0.03 to 3.5+/-1.1 micrograms/ml (P=0.03). IL-8 was below the detection limit of the ELISA (<25 pg/ml) in both studies. The increase of IL-6 and IL-1ra in response to high altitude was delayed and preceded the increase of CRP. We conclude that: (1) circulating IL-6, IL-1ra and CRP are upregulated in response to hypobaric hypoxic conditions at high altitude, and (2) the moderate systemic increase of these inflammatory markers may reflect considerable local inflammation. The existence and the kinetics of high altitude-induced cytokines found in this study support the hypothesis that inflammation is involved in the development of HAPO.
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806
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Brock M, Fischer R, Linder D, Buckel W. Methylcitrate synthase from Aspergillus nidulans: implications for propionate as an antifungal agent. Mol Microbiol 2000; 35:961-73. [PMID: 10712680 DOI: 10.1046/j.1365-2958.2000.01737.x] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Aspergillus nidulans was used as a model organism to investigate the fungal propionate metabolism and the mechanism of growth inhibition by propionate. The fungus is able to grow slowly on propionate as sole carbon and energy source. Propionate is oxidized to pyruvate via the methylcitrate cycle. The key enzyme methylcitrate synthase was purified and the corresponding gene mcsA, which contains two introns, was cloned, sequenced and overexpressed in A. nidulans. The derived amino acid sequence of the enzyme shows more than 50% identity to those of most eukaryotic citrate synthases, but only 14% identity to the sequence of the recently detected bacterial methylcitrate synthase from Escherichia coli. A mcsA deletion strain was unable to grow on propionate. The inhibitory growth effect of propionate on glucose medium was enhanced in this strain, which led to the assumption that trapping of the available CoA as propionyl-CoA and/or the accumulating propionyl-CoA itself interferes with other biosynthetic pathways such as fatty acid and polyketide syntheses. In the wild-type strain, however, the predominant inhibitor may be methylcitrate. Propionate (100 mM) not only impaired hyphal growth of A. nidulans but also synthesis of the green polyketide-derived pigment of the conidia, whereas in the mutant pigmentation was abolished with 20 mM propionate.
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807
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Stöger E, Vaquero C, Torres E, Sack M, Nicholson L, Drossard J, Williams S, Keen D, Perrin Y, Christou P, Fischer R. Cereal crops as viable production and storage systems for pharmaceutical scFv antibodies. PLANT MOLECULAR BIOLOGY 2000; 42:583-90. [PMID: 10809004 DOI: 10.1023/a:1006301519427] [Citation(s) in RCA: 158] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
This report describes the stable expression of a medically important antibody in the staple cereal crops rice and wheat. We successfully expressed a single-chain Fv antibody (ScFvT84.66) against carcinoembryonic antigen (CEA), a well characterized tumor-associated marker antigen. scFv constructs were engineered for recombinant antibody targeting to the plant cell apoplast and ER. Up to 30 microg/g of functional recombinant antibody was detected in the leaves and seeds of wheat and rice. We confirmed that transgenic dry seeds could be stored for at least five months at room temperature, without significant loss of the amount or activity of scFvT84.66. Our results represent the first transition from model plant expression systems, such as tobacco and Arabidopsis, to widely cultivated cereal crops, such as rice and wheat, for expression of an antibody molecule that has already shown efficacy in clinical applications. Thus, we have established that molecular pharming in cereals can be a viable production system for such high-value pharmaceutical macromolecules. Our findings provide a strong foundation for exploiting alternative uses of cereal crops both in industrialized and developing countries.
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808
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von Wasielewski R, Seth S, Franklin J, Fischer R, Hübner K, Hansmann ML, Diehl V, Georgii A. Tissue eosinophilia correlates strongly with poor prognosis in nodular sclerosing Hodgkin's disease, allowing for known prognostic factors. Blood 2000; 95:1207-13. [PMID: 10666192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023] Open
Abstract
Although eosinophilic granulocytes are frequently observed in lymphatic tissue of Hodgkin's patients, no substantial data reveal the prognostic role, if any, of tissue eosinophilia. Thus, eosinophilia was analyzed histologically in 1511 diagnostic biopsy specimens of patients treated under protocol therapy of the German Hodgkin's Lymphoma Study Group between 1988 and 1994. Prominent eosinophilia was seen in 38% of cases, which differed among the histologic types of Hodgkin's disease (HD): none in lymphocyte predominant, 14% in lymphocyte rich classical, 40% in nodular sclerosis grade 1 (NS-1), 55% in nodular sclerosis grade 2, 43% in mixed cellularity (MC), and 54% in lymphocyte depleted. In a multivariate analysis, tissue eosinophilia proved to be the strongest prognostic factor for freedom from treatment failure (P <. 001) and overall survival (P <.001) in a stage-stratified model. Among NS-1 patients, the effect was highly significant. In MC, no significant effect of eosinophilia on survival could be demonstrated. Eosinophils secrete CD30 ligand that is capable of binding to CD30 positive HD cells. The activation of TRAF2, followed by NF-kappaB, which occurs on CD30L/CD30 binding, may explain the neoplastic proliferation and apoptosis protection of HD cells. TRAF2 is also activated by EBV-LMP expression, which is detectable in the majority of MC but not NS cases. In addition to the possibility that eosinophils are only passive indicators for other unknown prognostic determinants, it may be concluded that the positive clinical outcome of eosinophilia-negative NS cases could be due to lower NF-kappaB activity. (Blood. 2000;95:1207-1213)
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809
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Wettstein M, Peters-Regehr T, Kubitz R, Fischer R, Holneicher C, Mönnighoff I, Häussinger D. Release of osmolytes induced by phagocytosis and hormones in rat liver. Am J Physiol Gastrointest Liver Physiol 2000; 278:G227-33. [PMID: 10666046 DOI: 10.1152/ajpgi.2000.278.2.g227] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Betaine, taurine, and inositol participate as osmolytes in liver cell volume homeostasis and interfere with cell function. In this study we investigated whether osmolytes are also released from the intact liver independent of osmolarity changes. In the perfused rat liver, phagocytosis of carbon particles led to a four- to fivefold stimulation of taurine efflux into the effluent perfusate above basal release rates. This taurine release was inhibited by 70-80% by the anion exchange inhibitor DIDS or by pretreatment of the rats with gadolinium chloride. Administration of vasopressin, cAMP, extracellular ATP, and glucagon also increased release of betaine and/or taurine, whereas insulin, extracellular UTP, and adenosine were without effect. In isolated liver cells, it was shown that parenchymal cells and sinusoidal endothelial cells, but not Kupffer cells and hepatic stellate cells, release osmolytes upon hormone stimulation. This may be caused by a lack of hormone receptor expression in these cells, because single-cell fluorescence measurements revealed an increase of intracellular calcium concentration in response to vasopressin and glucagon in parenchymal cells and sinusoidal endothelial cells but not in Kupffer cells and hepatic stellate cells. The data show that Kupffer cells release osmolytes during phagocytosis via DIDS-sensitive anion channels. This mechanism may be used to compensate for the increase in cell volume induced by the ingestion of phagocytosable material. The physiological significance of hormone-induced osmolyte release remains to be evaluated.
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810
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Fischer R, Hanson KM, Dose V. Background estimation in experimental spectra. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 2000; 61:1152-1160. [PMID: 11046387 DOI: 10.1103/physreve.61.1152] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/1999] [Indexed: 05/23/2023]
Abstract
A general probabilistic technique for estimating background contributions to measured spectra is presented. A Bayesian model is used to capture the defining characteristics of the problem, namely, that the background is smoother than the signal. The signal is allowed to have positive and/or negative components. The background is represented in terms of a cubic spline basis. A variable degree of smoothness of the background is attained by allowing the number of knots and the knot positions to be adaptively chosen on the basis of the data. The fully Bayesian approach taken provides a natural way to handle knot adaptivity and allows uncertainties in the background to be estimated. Our technique is demonstrated on a particle induced x-ray emission spectrum from a geological sample and an Auger spectrum from iron, which contains signals with both positive and negative components.
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811
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van Zyl JH, de K Grundling H, van Rensburg CJ, Retief FJ, O'Keefe SJ, Theron I, Fischer R, Bethke T. Efficacy and tolerability of 20 mg pantoprazole versus 300 mg ranitidine in patients with mild reflux-oesophagitis: a randomized, double-blind, parallel, and multicentre study. Eur J Gastroenterol Hepatol 2000; 12:197-202. [PMID: 10741935 DOI: 10.1097/00042737-200012020-00011] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
BACKGROUND AND AIM The aim of this study was to compare the efficacy and tolerability of low dose pantoprazole (20 mg) (a gastric proton pump inhibitor) with standard dose ranitidine (300 mg) (a histamine-receptor antagonist), in their ability to relieve symptoms and heal oesophageal lesions associated with gastrooesophageal reflux disease (GORD). METHODS Patients with endoscopically established mild GORD (stage I, modified Savary-Miller classification) were enrolled into a multicentre, randomized, double-blind, parallel-group comparison study (intention-to-treat population, n = 201; age range, 18-82 years). Patients took either oral pantoprazole 20 mg in the morning (n = 101) or ranitidine 300 mg in the evening (n = 100) once daily for 4 weeks or, if the healing was not complete, 8 weeks. Relief from key symptoms (heartburn, acid regurgitation, pain on swallowing) was assessed after 2, 4, and if applicable, 8 weeks. Healing of lesions was confirmed endoscopically after 4 and, if applicable, 8 weeks. RESULTS Complete relief from key symptoms was noted after 2 weeks in 70/88 (80%) patients treated with pantoprazole vs 45/89 (51%) patients treated with ranitidine ('per-protocol and key-point available' populations, P < 0.001); the corresponding results after 4 weeks were 77/88 (88%) vs 51/88 (58%) (P < 0.001). Complete healing of lesions after 4 weeks of treatment was seen in 74/88 (84%) vs 49/89 (55%) in the pantoprazole and ranitidine group, respectively (P < 0.001, per-protocol); by week 8 the cumulative healing rates were 84/88 (95%) vs 69/89 (78%) in the pantoprazole and ranitidine group, respectively (P < 0.001). For the intention-to-treat populations, the corresponding values for healing after 4 and 8 weeks were 73% vs 49% (P < 0.001) and 83% vs 69% (P < 0.05), respectively. Both study medications were well tolerated. CONCLUSION Compared to ranitidine 300 mg, the regimen with pantoprazole 20 mg provides faster relief from symptoms and is significantly more effective in healing of oesophageal lesions in patients with mild reflux-oesophagitis. Thus, the low dose of pantoprazole offers a treatment approach which minimizes drug exposure and costs while retaining high efficacy.
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812
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Yuan L, Lowell GH, Hoover DL, Colleton CA, Hammack CA, Young LD, Fischer R, Patchen ML, Cross AS. Kinetics of cellular and cytokine responses in a chimeric mouse model for the study of staphylococcal enterotoxin B pathogenesis. Immunol Lett 2000; 71:19-26. [PMID: 10709781 DOI: 10.1016/s0165-2478(99)00158-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The mechanisms by which superantigens, such as staphylococcal enterotoxin B (SEB), contribute to microbial pathogenicity have been poorly defined. The study of such pathogenic processes has been hampered by the lack of an adequate animal model. We utilized a previously described murine chimeric model to determine the cytokines and cell populations that might be involved in SEB toxicity. In the absence of bone marrow transplantation (BMT), all total body irradiated (TBI) mice died, while all transplanted mice survived up to 6 months. Compared with non-TBI and non-BMT mice, chimeric mice had an increased percentage of CD11b (Mac-1)-positive splenocytes (17 vs. 59%, P < 0.05) and decreased CD45R-positive (B) cells (33 vs. 6%, P < 0.05) at 6 weeks after BMT. The relative numbers of splenocyte CD4 and CD8 cells were similar in chimeric and normal mice. Susceptibility of chimeric animals to 10 or 100 microg SEB was time-dependent: no mice challenged at 2 weeks post-BMT died, but 15% of mice challenged at 4 weeks and 50% of those challenged at 6-8 weeks died. Compared with TBI and non-BMT C3H/HeJ mice, SEB-challenged chimeric mice at 6-8 weeks had (1) increased splenocyte mRNA expression for: IFN-gamma (3.5 x optimally at 1 h), TNF-alpha (6.5 x at 2 h), IL-6 (4.8 x at 4 h), IL-1beta (8.4 x at 4 h), IL-2 (4.7 x at 4 h), and IL-10 (3 x at 16 h), and (2) increased and earlier peak serum levels of IFN-gamma, IL-6, IL-1beta and IL-2, but no increase in serum TNF-alpha or IL-4. These data support the hypothesis that the decreased percentage of B cells and increased macrophages in chimeric mice lead to enhanced T cell-macrophage interactions after SEB administration and a lethal burst of T cell and macrophage cytokine release. This model will provide insight into cell populations and mechanisms that mediate superantigen-induced toxicity.
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813
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Fischer R, Lang SM, Steiner U, Toepfer M, Hautmann H, Pongratz H, Huber RM. Theophylline improves acute mountain sickness. Eur Respir J 2000; 15:123-7. [PMID: 10678632 DOI: 10.1183/09031936.00.15112300] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A randomized two-part study was conducted in order to determine the efficacy of theophylline in the treatment of acute mountain sickness during fast ascent to altitudes >2,500 m. Fourteen healthy male subjects participated in a randomized single-blind placebo-controlled crossover study carried out in a decompression chamber (simulated altitude 4,500 m). A second randomized single-blind, placebo-controlled study was conducted at a high-altitude research laboratory (3,454 m) and included 21 healthy male subjects. The study medication was either 375 mg oral slow-release theophylline (250 mg if <70 kg) or a matched placebo tablet taken twice daily. The acute mountain sickness score (AMSS) was assessed three times a day, beginning 18 h prior to altitude exposure and continuing for 18 h after altitude exposure. In addition, measurements of respiratory frequency, pulse rate, oxygen saturation and arterial blood gas levels were performed. Acute mountain sickness was significantly reduced by theophylline during the decompression chamber study (mean+/-SD 1.2+/-0.9) with placebo versus 3.6+/-0.8 with theophylline; p=0.03). During the high-altitude study, subjects with theophylline showed a significantly lower AMSS on arrival and after 18 h at altitude (0.6 versus 2.3, p=0.03). Oxygenation was improved in both parts of the study. In conclusion, oral slow-release theophylline improves acute mountain sickness.
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814
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Berg D, Hoggenmüller U, Hofmann E, Fischer R, Kraus M, Scheurlen M, Becker G. The basal ganglia in haemochromatosis. Neuroradiology 2000; 42:9-13. [PMID: 10663462 DOI: 10.1007/s002340050002] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Haemochromatosis is characterised by deposition of iron-containing pigment in various organs, but little is known about possible deposition in the brain and its clinical impact. We therefore investigated 14 patients with hereditary haemochromatosis with MRI, CT and transcranial ultrasound (TCS) and examined them neurologically. In six of the patients dense lesions were found within the lentiform nucleus on CT, all of whom displayed hyperechogenic lesions in the same area on TCS, as did one other patient. In these patients the relative signal intensities of the lentiform nucleus measured by MRI relaxometry were higher. No patient had clinical signs of basal ganglia disorders.
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815
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Poellinger B, Huber R, Fischer R, Hautmann H, Siefert A, Duehmke E. High-dose rate brachytherapy (HDR-BT): A prospective randomized trial of two fractionation schedules in the palliative treatment of central lung tumors. Int J Radiat Oncol Biol Phys 2000. [DOI: 10.1016/s0360-3016(00)80261-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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816
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Schillberg S, Tiburzy R, Fischer R. Transient transformation of the rust fungus Puccinia graminis f. sp. tritici. MOLECULAR & GENERAL GENETICS : MGG 2000; 262:911-5. [PMID: 10660051 DOI: 10.1007/pl00008658] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The biotrophic rust fungus Puccinia graminis f. sp. tritici (Pgt) was transformed by particle bombardment. The promoter from the Pgt translation elongation factor 1alpha (EF-1alpha) gene was fused to the bacterial marker genes hygromycin B phosphotransferase (hpt) and beta-glucuronidase (GUS). Transformation constructs were introduced into uredospores of Pgt, an obligate pathogen of wheat, by biolistic bombardment. Uredospores transformed with the construct containing the hpt gene germinated and initiated branching on selective medium, indicating that they had acquired resistance to hygromycin B. However, transformants stopped growing 5 days after bombardment. GUS activity in uredospores and germlings was histochemically detected 4-16 h after bombardment. GUS expression was also obtained using the INF24 promoter from the bean rust fungus Uromyces appendiculatus, demonstrating that heterologous genes can be expressed in P. graminis under the control of regulatory sequences from closely related organisms.
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817
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Thiele J, Kvasnicka HM, Schmitt-Graeff A, Zirbes TK, Birnbaum F, Kressmann C, Melguizo-Grahmann M, Frackenpohl H, Sprungmann C, Leder LD, Diehl V, Zankovich R, Schaefer HE, Niederle N, Fischer R. Bone marrow features and clinical findings in chronic myeloid leukemia--a comparative, multicenter, immunohistological and morphometric study on 614 patients. Leuk Lymphoma 2000; 36:295-308. [PMID: 10674901 DOI: 10.3109/10428190009148850] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
A multicenter, immunohistochemical and morphometric study was performed on diagnostic pretreatment bone marrow biopsies in 614 adult patients with Ph1+ chronic myeloid leukemia (CML) to compare histological features with clinical findings. For identification of megakaryopoiesis we used the monoclonal antibody CD61 and additionally the PAS reaction to determine the subfraction of atypical micromegakaryocytes and precursors. Labelling of erythroid precursors was carried out by a monoclonal antibody directed against glycophorin C. In order to selectively stain macrophages and their activated subset we applied CD68 and the GSA-I lectin. Density of argyrophilic fibers (reticulin plus collagen) was measured following Gomori's silver impregnation method. In accordance with laboratory data morphological variables revealed a comparable amount of congruence in the various groups of CML patients derived from different sources. In about 26% of patients early (reticulin) to advanced (collagen) fibrosis was detectable. Significant correlations were calculated between the extent of myelofibrosis with splenomegaly, anemia and increasing numbers of erythroblasts and myeloblasts in the peripheral blood count. These features were assumed to indicate more advanced stages of the disease process with ensuing transition into myeloid metaplasia and consequently were associated with an unfavorable prognosis. Significant relationships were revealed between the number of CD61+ megakaryocytes and more important, also their precursor fraction with the degree of fibrosis. This result extends previous experimental findings regarding the impact of immature elements of this cell lineage for the generation of myelofibrosis. The significant association of erythroid precursors with the number of mature (resident) macrophages including their activated GSA-I subset may shed some light on their functional involvement in iron turnover and hemoglobin synthesis. A modified histological classification of predominant bone marrow features is introduced. This simplified synthesis staging system (Cologne Classification) is not only associated with certain sets of laboratory data, but also with different survival patterns.
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818
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Fischer R, Merseburger A, Hecker H, Zywietz C. Determination of QT dispersion in view of measurement accuracy. J Electrocardiol 2000. [DOI: 10.1016/s0022-0736(00)80029-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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819
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Suelmann R, Fischer R. Mitochondrial movement and morphology depend on an intact actin cytoskeleton in Aspergillus nidulans. CELL MOTILITY AND THE CYTOSKELETON 2000; 45:42-50. [PMID: 10618165 DOI: 10.1002/(sici)1097-0169(200001)45:1<42::aid-cm4>3.0.co;2-c] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Mitochondria are essential organelles for the oxidative energy metabolism in eukaryotic cells. Determinants of mitochondrial morphology as well as the machinery underlying their subcellular distribution are not well understood. In this study we constructed an Aspergillus nidulans strain, in which mitochondria are stained with the green-fluorescent protein (GFP) to visualize them and study their behavior in vivo (http://www.uni-marburg. de/mpi/movies/mitochondria/mitochondria.html). Mitochondria form a complex membranous system in the cytoplasm consisting of interconnected tubular structures. Mitochondrial tubes separate frequently or produce small organelles that migrate some distance with velocities of up to 15 microm/min before they fuse again with the reticulum. Experiments using cytochalasin A as an anti-cytoskeletal drug revealed that a functional actin cytoskeleton is crucial for mitochondrial morphology and the dynamic behavior of the mitochondrial network. Movement of organelles along actin filaments requires actin-dependent motor proteins, such as myosin. We found that MyoA, a class I myosin motor of A. nidulans involved in vesicle migration, is not responsible for mitochondrial movement.
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820
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Bevier WC, Fischer R, Jovanovic L. Treatment of women with an abnormal glucose challenge test (but a normal oral glucose tolerance test) decreases the prevalence of macrosomia. Am J Perinatol 1999; 16:269-75. [PMID: 10586979 DOI: 10.1055/s-2007-993871] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Infant macrosomia is a serious medical concern. Pregnant women who do not meet the specific diagnosis for gestational diabetes may still have glucose-mediated macrosomia. In Santa Barbara County all pregnant women are screened for gestational diabetes at 24-28 weeks with a 50-g, 1-hr glucose challenge test (GCT). All patients who fail this test are placed on a standard euglycemic diet (40% carbohydrate, 20% protein, 40% fat) and perform home glucose monitoring of fasting and postprandial glucose levels. The objective of this study was to examine the effectiveness of this treatment program in decreasing infant macrosomia, maternal and infant morbidity, maternal complications, and operative delivery. We studied 103 women who had a positive GCT, but a negative 100-g, 3-hr oral glucose tolerance test (OGTT). The women were randomly assigned to either experimental or control groups with experimental women receiving dietary counseling and home glucose monitoring instruction (HBGM). HBGM diaries were reviewed weekly by clinic nurses. All women had hemoglobin A1c (HbA1c) tests at 28 and 32 weeks. Maternal and fetal charts were reviewed to determine delivery type and complications, indications for cesarean section (C-section), and infant gestational age, gender, Apgar scores, birth weight, morbidities, and congenital anomalies. Of the 103 women, 5 women required insulin treatment, 1 woman had an abortion, and 14 women were indeterminate regarding compliance or were control women who received diet counseling and HBGM. The results are based on 83 women--48 control and 35 experimental. There were no significant differences between the groups for age, parity, or weight at 28-30 weeks or 37 weeks to delivery, or HbA1c at 28 weeks. HbA1c was significantly higher in control women at 32 weeks. Birth weight expressed in grams or as a percentile specific for gender, ethnicity, and gestational age was significantly higher in control infants. Birth weight was significantly correlated with maternal intake weight, weight at 28-30 weeks, and weight at delivery and with HbA1c at 32 weeks' gestation. There were no significant differences between groups for maternal complications. Groups were significantly different for mode of delivery with experimental women having more induced vaginal deliveries but fewer repeat C-sections than control women. Groups were not different for primary C-sections. Women who fail the GCT, but not the OGTT and thus do not receive the diagnosis of GDM are still at risk for delivering a macrosomic infant and operative delivery. Our program of treatment for all women who fail the GCT improves outcome by reducing infant birth weight and the number of cesarean sections.
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821
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Betancourt L, Fischer R, Giannetta J, Malmud E, Brodsky NL, Hurt H. Problem-solving ability of inner-city children with and without in utero cocaine exposure. J Dev Behav Pediatr 1999; 20:418-24. [PMID: 10608371 DOI: 10.1097/00004703-199912000-00003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
To evaluate the problem-solving abilities of a cohort of inner-city cocaine-exposed children and controls, children were invited to play with the Goodman Lock Box, a large red and blue box with 10 compartments, each having a different lock and toy. Examiners, blinded to the children's group status, coded the children's activities during the 6.5-minute play period. Nineteen behaviors were collapsed into three outcomes: Aimless Actions, Competence, and Mental Organization. Groups' scores were compared with scores of the Goodman standardization sample of mixed socioeconomic status preschoolers. Seventy-three cocaine-exposed children and 82 controls were evaluated at age 3.5 years; of these, 58 cocaine-exposed and 63 controls were reevaluated at age 4.5 years. The groups' scores did not differ on any outcome at either time point (p > or = .22). However, both groups' Mental Organization scores were consistently lower than the Goodman group at each age (p < .01). This high-risk cohort may experience problems functioning in more complex environments such as the classroom.
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822
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Hellwig S, Robin F, Drossard J, Raven NP, Vaquero-Martin C, Shively JE, Fischer R. Production of carcinoembryonic antigen (CEA) N-A3 domain in Pichia pastoris by fermentation. Biotechnol Appl Biochem 1999; 30:267-75. [PMID: 10574697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Carcinoembryonic antigen (CEA) is a 180-kDa glycoprotein found on the surface of normal colon and malignant human adenocarcinomas. Recently, a fusion protein containing two of the seven Ig-like domains present in CEA (N and A3) has been constructed and expressed in Pichia pastoris [You, Hefta, Yazaki, Wu and Shively (1998) Anticancer Res. 18, 3193-3201]. Here, we report the generation and selection of a multi-copy clone expressing this fusion protein, the optimization of the shake-flask expression protocol and the upscaled production of CEA N-A3 using fermentation technology. P. pastoris transformants secreting the CEA N-A3 domain were generated by electrotransformation of the GS115 host strain with the pPIC9K vector containing the CEA N-A3 cDNA [You, Hefta, Yazaki, Wu and Shively (1998) Anticancer Res. 18, 3193-3201] then screened for CEA N-A3 expression and G418 resistance. The recombinant CEA N-A3 domain was detected in the culture supernatant using the monoclonal anti-CEA antibody T84.66. Optimization of methanol-induction conditions resulted in a high-methanol shake-flask expression protocol yielding significantly increased CEA N-A3 levels. Fermentation and culture conditions were optimized for 5-l working-volume fermentations and CEA N-A3 was affinity purified using Ni-IDA (imino di-acetic acid) affinity chromatography from the clarified fermentation supernatant. Peptide N-glycosidase F treatment revealed that the recombinant protein was heavily glycosylated but expressed as a single polypeptide of 28 kDa with no evidence of proteolytic degradation. Our results demonstrate that functional CEA N-A3 domain can be produced in sufficient quantities in P. pastoris for structural analysis or diagnostic applications. To our knowledge, this article represents the first report on the production of a human tumour antigen through fermentation.
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823
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824
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Thiele J, Kvasnicka HM, Fischer R. Histochemistry and morphometry on bone marrow biopsies in chronic myeloproliferative disorders - aids to diagnosis and classification. Ann Hematol 1999; 78:495-506. [PMID: 10602893 DOI: 10.1007/s002770050546] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The aim of this review is to evaluate morphological characteristics of the different subtypes of chronic myeloproliferative disorders (MPDs) derived by applying immunohistochemical and morphometric techniques to bone marrow biopsies and to combine these results with relevant clinical parameters. In comparison to control specimens, a significant decrease in erythroid precursors is determinable in chronic myeloid leukemia (CML), while this cell lineage is most prominent in polycythemia vera (PV) and moderately to markedly reduced in idiopathic myelofibrosis (IMF). On the other hand, neutrophilic granulopoiesis shows a predominance in CML and a relevant increase in PV, but no conspicuous changes are detectable in essential thrombocythemia (ET). CML is characterized by a prevalent growth of dwarflike micromegakaryocytes, occurring in particular in the so-called megakaryocyte-rich subtypes (about 30%). This finding differs significantly from the pleomorphous aspect, i.e. , clusters of small to giant-sized megakaryocytes in PV and the grossly abnormal (dysplastic) appearance of this cell lineage in patients with IMF. Similar cytological abnormalities of megakaryopoiesis consistent with maturation defects are never encountered in ET. The incidence of mature (resident) macrophages (phagocytic reticular cells) is significantly enhanced in IMF in comparison to the other MPDs and controls. Moreover, there is a striking difference in the density of reticulin-collagen fibers, ranging from normal (ET) to extreme values (IMF). In IMF more than 80% of the patients present with some degree of myelofibrosis-osteosclerosis at diagnosis, while the rest show an initial prefibrotic, hypercellular stage. This feature deserves special attention since, when accompanied by thrombocythemia, it may simulate ET. Sequential bone marrow biopsies in patients with IMF disclose that evolution of myelofibrosis is progressive, but occurs at a variable and unpredictable speed. A synoptical approach regarding clinical diagnosis and histological subtyping of MPDs is explicitly recommended and demonstrated by sets of diagnostic criteria. This rationale requires equal consideration of laboratory data and morphology by clinicians to include well-defined subtypes of MPDs into prospective management studies. Furthermore, it may even warrant follow-up studies and repeated bone marrow examinations in initially unclassifiable cases.
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825
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Ko S, Deiwick A, Jäger MD, Dinkel A, Rohde F, Fischer R, Tsui TY, Rittmann KL, Wonigeit K, Schlitt HJ. The functional relevance of passenger leukocytes and microchimerism for heart allograft acceptance in the rat. Nat Med 1999; 5:1292-7. [PMID: 10545996 DOI: 10.1038/15248] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
With an organ transplant, hematopoietic donor cells are transferred to the recipient. To study the relevance of the resulting microchimerism for allograft acceptance, we analyzed a rat model of cyclosporine-induced tolerance for strongly incompatible heart allografts. Using a monoclonal antibody that detects a donor-specific CD45 allotype (RT7a), we selectively depleted donor leukocytes at different times after transplantation (days 0 or 18). Depletion was similarly effective at both times. However, only depletion on day 0 prevented tolerance induction and was associated with severe acute or chronic graft rejection. This indicates that passenger leukocytes have an essential immunomodulatory effect on the induction phase of allograft acceptance.
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