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Meyer T, Vinkemeier U, Meyer U. [Assessment of the ethical consequences of genotype-based pharmacotherapy]. Dtsch Med Wochenschr 2002; 127:2524-6. [PMID: 12444566 DOI: 10.1055/s-2002-35638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Dänicke S, Gädeken D, Ueberschär KH, Meyer U, Scholz H. Effects of Fusarium toxin contaminated wheat and of a detoxifying agent on performance of growing bulls, on nutrient digestibility in wethers and on the carry over of zearalenone. ARCHIV FUR TIERERNAHRUNG 2002; 56:245-61. [PMID: 12462910 DOI: 10.1080/00039420214347] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Experiments were carried out to examine the effects of a Fusarium contaminated wheat (10 mg deoxynivalenol and 0.76 mg zearalenone, ZON, per kg dry matter) and of a detoxifying agent (Mycofix Plus, Biomin GmbH, Herzogenburg, Austria) on the growing performance of bulls, carry-over of ZON and its metabolites into body fluids and tissues, and on nutrient digestibility in wethers. The experiments were designed according to a complete two by two factorial approach which meant that both the uncontaminated control wheat and the Fusarium toxin contaminated wheat were tested both in the absence and presence of Mycofix Plus. The growing experiment with bulls (n = 14 per treatment) covered the live weight range between 244 kg and 460 kg. The respective wheat batches were included in the concentrate portion at 65%. Concentrates were fed according to plan whereas maize silage was offered for ad libitum consumption. Daily dry matter intake and live weight gain [kg per animal and day] were 7.40, 7.52, 7.51 and 7.49 and 1.367, 1.296, 1.380 and 1.307 for bulls fed the unsupplemented control wheat, the supplemented control wheat, the unsupplemented and Fusarium toxin contaminated wheat and the supplemented Fusarium toxin contaminated wheat, respectively. ZON and its metabolites were not detected in edible tissues. The most striking effects of feeding the Fusarium toxin contaminated wheat on carcass characteristics were a reduced dressing percentage, an increased weight of the emptied gastro-intestinal tract and a reduced weight of the testicles. No effect of the detoxifying agent was seen for these parameters whereas heart weight increased independently of Fusarium toxin contamination of the concentrates. Nutrient digestibility of the two wheat batches, unsupplemented or supplemented with Mycofix Plus was evaluated according to the difference method using wethers. Presence of Fusarium toxins in wheat did not influence its feeding value. The effects of the addition of the detoxifying agent were mycotoxin unspecific and resulted in an increase in apparent digestibility of crude protein and a decrease in crude fiber digestibility. It is concluded that feeding of Fusarium toxin contaminated wheat did not adversely affect performance of growing bulls (approximately 2.2 mg DON and 0.1 mg ZON per kg complete ration at a reference dry matter content of 88%) or nutrient digestibility in wethers. The effects of the detoxifying agent Mycofix Plus on growing performance and on nutrient digestibility were rather Fusarium toxin unspecific. The slightly negative effects on growing performance needs to be examined further.
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Mösche M, Meyer U. Toxicity of linear alkylbenzene sulfonate in anaerobic digestion: influence of exposure time. WATER RESEARCH 2002; 36:3253-3260. [PMID: 12188122 DOI: 10.1016/s0043-1354(02)00034-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The inhibition of anaerobic digestion by the anionic surfactant linear alkylbenzene sulfonate was studied. The development of bacterial activity during several weeks was monitored by performing batch degradation tests with acetate and propionate. In the first phase the decay of activity without surfactant addition was studied. After the addition of the surfactant an immediate inhibition was detected. Subsequently, the degradation activity continued to decrease with increasing exposure time. Both, the immediate inhibition and the rate of the subsequent decrease of activity were dependent on the surfactant concentration. A kinetic model is presented that describes this behavior. A surfactant concentration of 14 mg L(-1) causes a 50% immediate inhibition of acetate degradation (27 mg L(-1) in the case of propionate degradation). Additionally, each 12 mg L(-1) of surfactant increases the decay rate of acetate degradation activity by a factor 10 (23 mg L(-1) for propionate degradation). A deviation from this model occurs at low surfactant concentrations (<3 mg L(-1)), where a slight stimulation of bacterial activity was observed. The above-mentioned concentrations refer to measured surfactant concentrations. These were substantially lower than the nominal concentrations (added surfactant per volume). This discrepancy is explained by adsorption of the surfactant to the biomass. Finally, the importance of the presented kinetic model and the significance of surfactant toxicity for anaerobic digestion are discussed.
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Meyer U, van Kampen M, Isovich E, Flügge G, Fuchs E. Chronic psychosocial stress regulates the expression of both GR and MR mRNA in the hippocampal formation of tree shrews. Hippocampus 2002; 11:329-36. [PMID: 11769314 DOI: 10.1002/hipo.1047] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A persistent hyperactivity of the hypothalamic-pituitary-adrenal axis and thus elevated glucocorticoid levels are main neuroendocrine features of depressive symptomatology in humans. The broad range of effects that are set off by glucocorticoids is mediated by glucocorticoid receptors (GRs) and mineralocorticoid receptors (MRs), which themselves are subject to autoregulation. In order to investigate the impact of long-lasting psychological stress on corticosteroid receptor mRNA expression in the hippocampal formation, we employed the psychosocial stress paradigm in male tree shrews (Tupaia belangeri). By in situ hybridization studies and semiquantitative evaluation of stress-induced changes of GR and MR mRNA expression at the single-cell level, brain tissue from subordinate animals which were exposed to 27 days (1 h/day) of social confrontation was compared to that of nonstressed animals. Four weeks of stress exposure resulted in a downregulation of GR mRNA in the dentate gyrus and hippocampal subfields CA1 and CA3 of subordinate male tree shrews compared to controls. The MR mRNA content in these subfields of the anterior hippocampus was also clearly reduced. On the contrary, in a more posterior location on the longitudinal axis of the tree shrew hippocampus, the MR message was increased in subfields CA1 and CA3 and in the dentate gyrus. These results suggest a relevance of the stress-induced regulation of both corticosteroid receptor subtype mRNAs in a naturalistic challenging situation. Moreover, the differential regulation of MR mRNA along the rostrocaudal axis of the hippocampus adds another feature to the heterogenous composition of this structure.
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Feitkenhauer H, Meyer U. Mikrobielle Textilveredlung mit anaeroben Mischkulturen: Integration von Abwasserreinigung und Produktion. CHEM-ING-TECH 2002. [DOI: 10.1002/1522-2640(200205)74:5<678::aid-cite678>3.0.co;2-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Aracama M, Esteruelas MA, Lahoz FJ, Lopez JA, Meyer U, Oro LA, Werner H. Synthesis, reactivity, molecular structure, and catalytic activity of the novel dichlorodihydridoosmium(IV) complexes OsH2Cl2(PR3)2 (PR3 = P-i-Pr3, PMe-t-Bu2). Inorg Chem 2002. [DOI: 10.1021/ic00002a025] [Citation(s) in RCA: 166] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Feitkenhauer H, Meyer U. Anaerobic digestion of alcohol sulfate (anionic surfactant) rich wastewater--batch experiments. Part II: influence of the hydrophobic chain length. BIORESOURCE TECHNOLOGY 2002; 82:123-129. [PMID: 12003312 DOI: 10.1016/s0960-8524(01)00174-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
High-strength wastewater of some industries contains high concentrations of surfactants and readily biodegradable compounds like starch and other carbohydrates. Wastewater of this type is found in the textile wet-processing industry (e.g., cotton desizing). The anaerobic degradation process in such wastewater is inhibited due to the high surfactant content. Alcohol sulfate (AS) of increasing hydrophobic chain length (C8 to C18, surfactant) and soluble starch (size) were used as model compounds in a series of batch experiments with high loadings of the biomass (65 g AS/kg cell dry weight; 910 g starch/kg cell dry weight). The strongest inhibition of the hydrolysis, acidogenesis and acetogenesis was found in reactors containing medium chain ASs like dodecyl sulfate. Starch hydrolyzation rates decreased by nearly 90% in the presence of dodecyl sulfate. Decyl sulfate caused the strongest inhibition of the methanogenesis and a decrease of the methane evolution by 75% within 87 days experimental time. It was found that short as well as long chain ASs caused only minor inhibition phenomena. The presented data can be used as a basis for the selection of suitable surfactants that do not (or not seriously) inhibit the anaerobic digestion of industrial effluents.
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Meyer U, Stamm T, Meier N, Joos U. First experience with a public domain computer-aided surgical system. Br J Oral Maxillofac Surg 2002; 40:96-104. [PMID: 12180219 DOI: 10.1054/bjom.2001.0739] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The outcome of complex craniofacial operations is critically dependent on careful and accurate preoperative planning. Recent advances in computer technology enable the surgeon to do surgical simulations directly on to a computer terminal. We describe the clinical application of a public domain-based computer-aided system in craniofacial surgery. Operation planning was based on clinical investigations and radiological images, with particular use of a virtual three-dimensional surgical simulation. Three patients with complex craniofacial malformations were admitted for orbital correction. Surgical simulation defined numerically the extent of bone movements and the extent of resection areas. Operations were guided by the virtual planning. The outcome was compared with the planning to assess the accuracy of the operative correction. Our first experience confirms that computer-assisted simulation is a reliable and useful tool that improves surgical planning and helps to evaluate the surgical outcome.
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Feitkenhauer H, Meyer U. Anaerobic digestion of alcohol sulfate (anionic surfactant) rich wastewater--batch experiments. Part I: influence of the surfactant concentration. BIORESOURCE TECHNOLOGY 2002; 82:115-121. [PMID: 12003311 DOI: 10.1016/s0960-8524(01)00173-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Textile wet processing wastewater (e.g., from cotton desizing) contains high concentrations of surfactants as well as readily biodegradable compounds like starch and other carbohydrates. Decyl sulfate (DS, surfactant) and soluble starch were used as model pollutants for biodegradation batch experiments. Very high loadings of the biomass were applied (DS: 21.7-217 g/kg cell dry weight (CDW); starch: 910 g/kg cell dry weight) to study inhibitory effects of the surfactant on the degradation cascade of the biopolymer. The starch hydrolysis was inhibited above sludge loadings of 65 g DS/kg CDW. Acidogenesis was the degradation step with the highest resistance towards inhibitory effects of the surfactant, whereas methanogenesis proved to be the most sensitive. The effects of the surfactant were described by the change of the methane evolution, which was reduced by 50% in 87 days with an addition of 58 g DS/kg CDW. The surfactant caused a high temporary accumulation of intermediates like volatile fatty acids. At the highest loading (217 g DS/kg CDW) the conversion of the substrate to methane was only minor.
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Dänicke S, Gädeken D, Ueberschär KH, Meyer U, Scholz H. Effects ofFusarium-toxincontaminated wheat in ruminant nutrition. Mycotoxin Res 2002; 18 Suppl 1:24-7. [DOI: 10.1007/bf02946056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Piffko J, Meyer U, Joos U. [Possibilities and limitations in evaluating treatment concepts in lip-jaw-palate clefts]. MUND-, KIEFER- UND GESICHTSCHIRURGIE : MKG 2002; 6:49-52. [PMID: 11974546 DOI: 10.1007/s10006-001-0349-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Recently, government and medical practitioners have shown considerable interest in the discipline of evidence-based medicine. LITERATURE RESEARCH AND RESULTS In this study, we investigated the literature concerning treatment concepts in cleft surgery according to criteria of evidence-based medicine. Over the last decade 996 articles on cleft patients were published, 181 of which were studies evaluating the clinical outcome of distinct treatment options. Only 57 studies proved to be classifiable due to a well-described study protocol. One treatment study of cleft patients reached the strength of evidence grade I and strength of recommendation grade A, whereas all other studies had a lower evidence rating. DISCUSSION The reasons behind these findings seem to be due to problems faced by the specialty of this disease.
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Feitkenhauer H, Meyer U. On-line titration of non-ionic surfactants in wastewater treatment plants using a specific electrode. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2002; 45:61-68. [PMID: 11936676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Textile finishing industry wastewater often contains high concentrations of surfactants. Non-ionic surfactants like alcohol ethoxylates are among the most used surfactants and are discharged from batch-processes in widely varying concentrations. The anaerobic biomass and especially methanogenic microorganisms have been shown to be inhibited by surfactants. To protect these microorganisms from irreversible inhibition a measurement of the surfactant concentration is useful for the process control, but most analytical methods are too complicated and expensive for an on-line process control. It was shown that the titration of non-ionic surfactants is possible in the presence of biomass and in wastewater from textile wet processes using the Metrohm NIO-electrode. Titration and sampling were successfully performed with standard equipment. The software used for the process control of a lab-scale anaerobic treatment plant was also used to evaluate the obtained titration curves. This allowed performing the titrations without using a more expensive titrator.
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Meyer U. From khellin to sodium cromoglycate--a tribute to the work of Dr. R. E. C. Altounyan (1922-1987). DIE PHARMAZIE 2002; 57:62-9. [PMID: 11836935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Sodium cromoglycate, which was launched in 1968 by the British company Fisons for the treatment of allergies and asthma, was an absolute novelty in chemical, pharmacological as well as therapeutic respects. The khellin derivative meanwhile did not owe its discovery to the usual strategies for finding drugs. On the contrary, the protective effect of the substance was discovered in a self trial through systematic antigen-induced provocation tests of the medicinal doctor and allergic Roger Ernest Collingwood Altounyan (1922-1987). The only subsequently formed hypothesis of a mast cell stabilising effect of Sodium cromoglcycate did not prove to be valid for the search for similar or more effective substances. A further development of this drug class could not take place because of the lack of suitable pharmacological models.
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Handschel J, Sunderkötter C, Kruse-Lösler B, Prott FJ, Meyer U, Piffko J, Joos U. Late effects of radiotherapy on oral mucosa in humans. Eur J Oral Sci 2001; 109:95-102. [PMID: 11347662 DOI: 10.1034/j.1600-0722.2001.00975.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In order to gain further understanding of the late effects of radiotherapy on oral mucosa, we analysed the histomorphological alterations, the cell populations in the subepithelial tissue, and the endothelial expression pattern of different adhesion molecules. Biopsies were taken from patients before irradiation, directly after 60 Gy, and 6-12 months after radiotherapy. Besides the histomorphological evaluation of the vessels, the endothelial expression of ICAM-1, VCAM-1 and E-selectin was determined as well as the distribution of LFA-1-, Mac-1-, VLA-4-, RM3/1-, 27E10- and 25F9-bearing cells in the subepithelial tissue. The expression of ICAM-1 was downregulated after radiotherapy, whereas the percentage of LFA-1- and VLA-4-bearing cells increased. VCAM-1 remained at low levels. The subepithelial infiltration was still dominated by RM3/1-positive macrophages. The number of vessels decreased, while the lumen of the remaining vessels increased. In conclusion, the late effects of radiotherapy are characterized by a decreased number of blood vessels and by significantly different expression patterns of the adhesion molecules studied, and of integrins and macrophage subpopulations, compared to the conditions before irradiation and directly after irradiation with 60 Gy.
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Kruse-Lösler B, Meyer U, Flören C, Joos U. Influence of distraction rates on the temporomandibular joint position and cartilage morphology in a rabbit model of mandibular lengthening. J Oral Maxillofac Surg 2001; 59:1452-9; discussion 1460-1. [PMID: 11732033 DOI: 10.1053/joms.2001.28281] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE Although various aspects of bone formation during distraction osteogenesis have been studied extensively, there are only limited experimental data concerning the influence of mandibular distraction rates on structural alterations in the temporomandibular joint (TMJ). In this study, a rabbit model of unilateral mandibular distraction was used to test the effects of various strain schedules on the position and morphology of the TMJ. MATERIAL AND METHODS Fifty-two immature white female rabbits were used. The distraction procedure was performed using physiologic (2,000 microstrains, 1 per day) and elevated strain magnitudes (20,000 microstrains, 1 per day), as well as high strain magnitudes (200,000 and 300,000 microstrains, 1 per day). The investigation of the TMJ included clinical, radiologic, and histologic aspects. RESULTS Clinical and radiologic examinations at the end of the distraction period showed no evidence of joint luxation even at maximal distraction rates. Histologic and ultrastructural analyses revealed a positive correlation between the degree of mechanical loading and the development of degenerative alterations in the cartilage. In samples distracted at hyperphysiologic strain magnitudes, all cartilaginous layers were reduced in the regions of the TMJ that had been exposed to the higher pressure forces. The fibrous layer became nearly completely destroyed. CONCLUSIONS These experimental data show that distraction schedules with single but hyperphysiologic loads may lead to degenerative or even early arthrotic changes in the condyle. These data support the principle that distraction protocols should be performed without extensive mechanical loading on the TMJ.
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Meyer U, Meyer T, Wiesmann HP, Kruse-Lösler B, Vollmer D, Stratmann U, Joos U. Mechanical tension in distraction osteogenesis regulates chondrocytic differentiation. Int J Oral Maxillofac Surg 2001; 30:522-30. [PMID: 11829235 DOI: 10.1054/ijom.2001.0159] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Differentiation of chondrocytes to cells of osteoblastic phenotype occurs during an interim period of bone development, fracture repair and distraction osteogenesis. To study the relationship between tension-stress and chondrogenesis, uniaxial strains (0 microstrains, 2000 microstrains, 20000 microstrains, 200000 microstrains, 300000 microstrains) were applied in a rabbit model of mandibular distraction osteogenesis. The results demonstrated that cell differentiation, apoptosis and tissue development in the newly formed gap tissue showed a correlation to the applied strain magnitudes. Only strains of 20000 microstrains resulted in a statistically significant (P<0.05) formation of cartilage struts with embedded chondrocyte-like cells. However, chondrocyte-like cells were rarely detected in samples distracted at lower or higher strain magnitudes. Osteoblasts appeared to replace cartilaginous matrix by mineralized bone matrix. The phenotypic change from chondrocytes to osteoblasts was accompanied by a decreased proteoglycan synthesis. a change in the expression from type II collagen towards type I and involved asymmetric cell divisions and apoptotic cell death. Therefore, we suggest that mechanical strain is an external stimulus responsible for phenotypic cell alterations.
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Ottermann B, Meyer U. [Not Available]. WURZBURGER MEDIZINHISTORISCHE MITTEILUNGEN 2001; 5:311-21. [PMID: 11631106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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Meyer U, Wiesmann HP, Meyer T, Schulze-Osthoff D, Jäsche J, Kruse-Lösler B, Joos U. Microstructural investigations of strain-related collagen mineralization. Br J Oral Maxillofac Surg 2001; 39:381-9. [PMID: 11601821 DOI: 10.1054/bjom.2001.0627] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Distraction osteogenesis in rabbit mandibles after osteotomy can be used as an experimental model to study the microstructural features of mineralization of callus under defined mechanical loads. Our aim was to study the relation between the micromotions in the gap and the resulting features of mineralization of the matrix. We found that assembly of collagen and formation of crystals depended on the magnitude of the mechanical stress applied. At physiological bone strains (2000 microstrains), the callus had collagen type I in a mature bone-like extracellular arrangement, whereas at 20000 microstrains bundles were orientated predominantly towards the tension vector. Maximum loads (200000 microstrains) resulted in disorganized assembly of the collagen. Quantitative energy-dispersive analysis by X-rays confirmed that high strains were associated with substantially lower concentrations of calcium and phosphate. In contrast to bone-like apatitic formation of crystals at physiological strains, significantly fewer but larger crystals were detected by electron diffraction analysis in samples exposed to high strains. We suggest that mechanical stress regulates the assembly and mineralization of collagen during distraction osteogenesis.
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Fraering P, Imhof I, Meyer U, Strub JM, van Dorsselaer A, Vionnet C, Conzelmann A. The GPI transamidase complex of Saccharomyces cerevisiae contains Gaa1p, Gpi8p, and Gpi16p. Mol Biol Cell 2001; 12:3295-306. [PMID: 11598210 PMCID: PMC60174 DOI: 10.1091/mbc.12.10.3295] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Gpi8p and Gaa1p are essential components of the GPI transamidase that adds glycosylphosphatidylinositols (GPIs) to newly synthesized proteins. After solubilization in 1.5% digitonin and separation by blue native PAGE, Gpi8p is found in 430-650-kDa protein complexes. These complexes can be affinity purified and are shown to consist of Gaa1p, Gpi8p, and Gpi16p (YHR188c). Gpi16p is an essential N-glycosylated transmembrane glycoprotein. Its bulk resides on the lumenal side of the ER, and it has a single C-terminal transmembrane domain and a small C-terminal, cytosolic extension with an ER retrieval motif. Depletion of Gpi16p results in the accumulation of the complete GPI lipid CP2 and of unprocessed GPI precursor proteins. Gpi8p and Gpi16p are unstable if either of them is removed by depletion. Similarly, when Gpi8p is overexpressed, it largely remains outside the 430-650-kDa transamidase complex and is unstable. Overexpression of Gpi8p cannot compensate for the lack of Gpi16p. Homologues of Gpi16p are found in all eucaryotes. The transamidase complex is not associated with the Sec61p complex and oligosaccharyltransferase complex required for ER insertion and N-glycosylation of GPI proteins, respectively. When GPI precursor proteins or GPI lipids are depleted, the transamidase complex remains intact.
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Feitkenhauer H, Meyer U. Integration of biotechnological wastewater treatment units in textile finishing factories: from end of the pipe solutions to combined production and wastewater treatment units. J Biotechnol 2001; 89:185-92. [PMID: 11500212 DOI: 10.1016/s0168-1656(01)00297-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Increasing costs for water, wastewater and energy put pressure on textile finishing plants to increase the efficiency of wet processing. An improved water management can decrease the use of these resources and is a prerequisite for the integration of an efficient, anaerobic on-site pretreatment of effluents that will further cut wastewater costs. A two-phase anaerobic treatment is proposed, and successful laboratory experiments with model effluents from the cotton finishing industry are reported. The chemical oxygen demand of this wastewater was reduced by over 88% at retention times of 1 day or longer. The next step to boost the efficiency is to combine the production and wastewater treatment. The example of cotton fabric desizing (removing size from the fabric) illustrates how this final step of integration uses the acidic phase bioreactor as a part of the production and allows to close the water cycle of the system.
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Monnerjahn C, Techel D, Meyer U, Rensing L. The grp78 promoter of Neurospora crassa: constitutive, stress and differentiation-dependent protein-binding patterns. Curr Genet 2001; 39:319-26. [PMID: 11525405 DOI: 10.1007/s002940100202] [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: 10/27/2022]
Abstract
In order to characterize the transcriptional regulation of the grp78 (glucose-regulated protein 78 kDa) gene of Neurospora crassa, a 1.65-kb genomic fragment upstream of the protein-coding region was sequenced and analysed. A single transcription start point was mapped 160 nt upstream of the first codon. Several distinct protein-DNA binding sites were identified in the promoter region by non-radioactive scanning electrophoretic mobility shift analysis during growth, stress treatment and differentiation of conidia. A protein DNA binding complex induced by tunicamycin was linked to a promoter motif similar to the unfolded protein response element consensus of yeast. Another binding complex in differentiating aerial hyphae was found, which differs from the known cis-elements involved in conidiation-dependent gene expression.
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Meyer U, Terodde M, Joos U, Wiesmann HP. [Mechanical stimulation of osteoblasts in cell culture]. MUND-, KIEFER- UND GESICHTSCHIRURGIE : MKG 2001; 5:166-72. [PMID: 11432332 DOI: 10.1007/s100060100293] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND Mechanical loading of bone is known to play a crucial role in bone remodeling and regeneration. Whereas the clinical effects of mechanically modulated bone healing have been extensively studied, less is known about the underlying mechanisms on a cellular level. This study was aimed at investigating the effects of uniaxial strains on osteoblast-like cells in culture. Mechanical loading was applied in physiological and hyperphysiological magnitudes. Nonstimulated cultures served as controls. RESULTS Cultured primary bovine periosteal cells exhibited phenotypic features of osteoblast-like cells. Application of physiological strains (2,000 mu strain) led to a bone-specific expression of extracellular matrix proteins (osteonectin, osteocalcin, collagen type I). Hyperphysiological loads (10,000 mu strain) were associated with an increased synthesis of proteoglycans. Proliferation of cells was higher than the controls at 10,000 mu strain and showed no difference from physiologically loaded osteoblasts. DISCUSSION Our study demonstrates that physiological loading of osteoblast-like cells enhances the regenerative capacity of bone, whereas hyperphysiological loads may impair bone regeneration.
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Meyer U, Vollmer D, Runte C, Bourauel C, Joos U. Bone loading pattern around implants in average and atrophic edentulous maxillae: a finite-element analysis. J Craniomaxillofac Surg 2001; 29:100-5. [PMID: 11465432 DOI: 10.1054/jcms.2001.0198] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION Oral implants placed in the maxilla, especially the posterior region, have a lower success rate than those placed in the mandible. Poor bone quantity and quality have been suggested as a reason for this differential success rate. OBJECTIVE The purpose of this study was, therefore, to evaluate stress and strain distributions around loaded implants in the normal and atrophic maxilla by finite-element (FE) analyses. MATERIAL FE models of a solitary implant were generated to determine stresses and strains in the bone adjacent to the implant surface under loading conditions. STUDY DESIGN Different bony situations and implant lengths were used in a FE model. Static loads were applied axially and the resulting stresses and strains calculated. RESULTS Bone quality and quantity play a major role in decreasing bone strains adjacent to the implant surface under loading. It was found that stresses were more homogeneously distributed when more spongy bone was present. Decreased bone height was found to have less pronounced effects on strain and stress alterations than poor bone quality. Atrophic bony dimensions in combination with poor bone quality were associated with surface strains exceeding physiological levels (> 6,000 microstrains). CONCLUSION Our investigation indicates that supraphysiological bone strains adjacent to the implant surface should be expected under mechanical loading in the atrophic maxilla.
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Handschel J, Sunderkötter C, Prott FJ, Meyer U, Kruse-Lösler B, Joos U. Increase of RM3/1-positive macrophages in radiation-induced oral mucositis. J Pathol 2001. [PMID: 11180172 DOI: 10.1002/1096-9896(2000)9999:9999<::aid-path754>3.0.co;2-p] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The purpose of this study was to describe the distribution patterns of various leukocyte subpopulations in the oral mucosa during the course of radiotherapy and to determine whether there are dose-dependent alterations, or any correlation between the clinical stages and the population density of specific leukocytes. The distribution and density of various leukocytes in oral mucosa in 13 head and neck cancer patients were immunohistochemically analysed before radiotherapy at 30 and 60 Gy and compared with the clinical degree of oral mucositis. Antibodies were used which characterized different subtypes of macrophages (27E10, 25F9, RM3/1) and recognized epitopes of granulocytes (CD15) and T cells (CD3, CD4, CD8). The study showed that whereas macrophages reactive with RM3/1 increased significantly at 30 Gy (p<0.01) and showed a further increase at 60 Gy (p<0.01), no significant alterations could be detected in the density of macrophages which stained positively for 27E10 or 25F9. Moreover, the percentage of macrophages reactive with RM3/1 showed a non-linear correlation with the clinical mucositis score (p<0.05). No significant alterations were detected in the percentage of T cells and granulocytes, compared with the values before radiotherapy. In conclusion, radiation-induced mucositis is characterized by features of an intermediate stage of an inflammatory response, suggesting active involvement of down-regulatory macrophages in its pathogenesis.
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