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  • 1
    ISSN: 1432-1076
    Keywords: Infantile muscular glycogenosis type II ; “Floppy infant” ; Acid maltase (α-1,4-glucosidase) deficiency
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung Es wird über eine “abortive muskuläre Form” der Typ II-Glykogenose (Pompe) bei drei Geschwistern (zwei Buben und deren Schwester) berichtet. Die klinischen und routinehistologischen Befunde entsprechen dem Bild einer primär degenerativen Myopathie. Erst spezielle lichtmikroskopische (PAS-Reaktion), elektronenmikroskopische und biochemische Untersuchungen führten zur Sicherung der Diagnose. Im elektronenmikroskopischen Bild weisen die betroffenen Muskelzellen aller drei Geschwister große, autophage Vacuolen auf, die neben aggregierten Glykogengranula häufig myelinartige Abbauprodukte cytoplasmatischer Membranen enthalten. Daneben werden unspezifische Veränderungen an den übrigen Zellorganellen und den Myofibrillen beobachtet. Die biochemische Untersuchung einer Muskelbiopsie ergibt den Nachweis eines Mangels an α-1,4-Glucosidase.
    Notes: Summary This report describes a mild muscular form of type II glycogenosis (Pompe) in 3 children (two boys and their sister). The clinical picture and results of routine histological tests were in keeping with the picture of a primary degenerative myopathy. It was not possible to confirm the diagnosis until special preparations were examined by light microscopy (PAS stain) and by electromicroscopical and biochemical techniques. Electron-microscopical examination of muscle cells from the affected areashowed large, autophagic vacuoles in all three sibs, which contained aggregated glycogen granules and myelin-like degradation products of cytoplasmic membranes. Nonspecific changes of the other cell organelles and the myofibrils were also observed. Biochemical examination of a muscle biopsy revealed an α-1,4-glucosidase deficiency.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 95 (1991), S. 324-331 
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Applied microbiology and biotechnology 52 (1999), S. 289-297 
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract 1,3-Propanediol (1,3-PD) production by fermentation of glycerol was described in 1881 but little attention was paid to this microbial route for over a century. Glycerol conversion to 1,3-PD can be carried out by Clostridia as well as Enterobacteriaceae. The main intermediate of the oxidative pathway is pyruvate, the further utilization of which produces CO2, H2, acetate, butyrate, ethanol, butanol and 2,3-butanediol. In addition, lactate and succinate are generated. The yield of 1,3-PD per glycerol is determined by the availability of NADH2, which is mainly affected by the product distribution (of the oxidative pathway) and depends first of all on the microorganism used but also on the process conditions (type of fermentation, substrate excess, various inhibitions). In the past decade, research to produce 1,3-PD microbially was considerably expanded as the diol can be used for various polycondensates. In particular, polyesters with useful properties can be manufactured. A prerequisite for making a “green” polyester is a more cost-effective production of 1,3-PD, which, in practical terms, can only be achieved by using an alternative substrate, such as glucose instead of glycerol. Therefore, great efforts are now being made to combine the pathway from glucose to glycerol successfully with the bacterial route from glycerol to 1,3-PD. Thus, 1,3-PD may become the first bulk chemical produced by a genetically engineered microorganism.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Applied microbiology and biotechnology 50 (1998), S. 24-29 
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Klebsiella pneumoniae was shown to convert glycerol to 1,3-propanediol, 2,3-butanediol and ethanol under conditions of uncontrolled pH. Formation of 2,3-butanediol starts with some hours' delay and is accompanied by a reuse of the acetate that was formed in the first period. The fermentation was demonstrated in the type strain of K. pneumoniae, but growth was better with the more acid-tolerant strain GT1, which was isolated from nature. In continuous cultures in which the pH was lowered stepwise from 7.3 to 5.4, 2,3-butanediol formation started at pH 6.6 and reached a maximum yield at pH 5.5, whereas formation of acetate and ethanol declined in this pH range. 2,3-Butanediol and acetoin were also found among the products in chemostat cultures grown at pH 7 under conditions of glycerol excess but only with low yields. At any of the pH values tested, excess glycerol in the culture enhanced the butanediol yield. Both effects are seen as a consequence of product inhibition, the undissociated acid being a stronger trigger than the less toxic diols and acid anions. The possibilities for using the fermentation type described to produce 1,3-propanediol and 2,3-butanediol almost without by-products are discussed.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 0006-3592
    Keywords: Klebsiella pneumoniae ; glycerol ; pyruvate kinase ; pyruvate:formate-lyase ; pyruvate dehydrogenase ; in vitro and in vivo activities ; dynamics ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The activities of pyruvate kinase (PK), pyruvate: formate-lyase (PFL), pyruvate dehydrogenase (PDH), and citrate synthase (CS) involved in the anaerobic glycerol conversion by Klebsiella pneumoniae were studied in continuous culture under conditions of steady states and sustained oscillations. Both the in vitro and in vivo activities of PK, PFL, and PDH are strongly affected by the substrate concentration and its uptake rate, as is the in vitro activity of CS. The flux from phosphoenolpyruvate to pyruvate is found to be mainly regulated on a genetic level by the synthesis rate of PK, particularly at low substrate concentration and low growth rate. In contrast, the conversion of pyruvate to acetyl-CoA is mainly regulated on a metabolic level by the in vivo activities of PFL and PDH. The ratio of in vitro to in vivo activities is in the range of 1 to 1.5 for PK, 5 to 17 for PFL and 5 to 80 for PDH under the experimental conditions. The regulation of in vivo activity and synthesis of these enzymes is sensitive to fluctuations of culture conditions, leading to oscillations of both the in vitro and in vivo activities. In particular, PFL is strongly affected during oscillations; its average in vitro activity is only about half of its corresponding steady-state value under similar environmental conditions. The average in vitro activities of PDH and PK under oscillations are close to their corresponding steady-state values. In contrast to all other enzymes measured for the glycerol metabolism by K. pneumoniae PFL and PDH are more effectively in vivo utilized under oscillations than under steady state, underlining the peculiar role of pyruvate metabolism in the dynamic responses of the culture. © 1998 John Wiley & Sons, Inc. Biotechnol Bioeng 60: 617-626, 1998.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 0006-3592
    Keywords: Klebsiella pneumoniae ; glycerol dissimilation ; 1,3-propanediol ; in vitro and in vivo enzyme activities ; dynamics ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The initial steps of glycerol dissimilation and 1,3-propanediol (1,3-PD) formation by Klebsiella pneumoniae anaerobically grown on glycerol were studied by quantifying the in vitro and in vivo activities of enzymes in continuous culture under conditions of steady state and oscillation and during transient phases. The enzymes studied included glycerol dehydrogenase (GDH), glycerol dehydratase (GDHt), and 1,3-propanediol oxidoreductase (PDOR). Three conclusions can be drawn from the steady-state results. First, glycerol concentration in the culture is a key parameter that inversely affects the in vitro activities (concentrations) of all three enzymes, but has a positive effect on their in vivo activities. Growth rate significantly affects the ratio of in vitro and in vivo enzyme activities under low glycerol concentrations, but not under glycerol excess. Second, whereas the flux through the oxidative pathway of glycerol dissimilation is governed mainly by the regulation of in vivo enzyme activity on a metabolic level, the flux through the reductive pathway is largely controlled by the synthesis of enzymes. Third, GDHt is a major rate-liming enzyme for the consumption of glycerol and the formation of 1,3-PD in K. pneumoniae at high glycerol concentrations. Results from oscillating cultures revealed that both in vitro and in vivo activities of the enzymes oscillated. The average values of the in vitro activities during an oscillation cycle agreed well with their corresponding values for nonoscillating cultures under similar environmental conditions. Experiments with step changes in the feed concentration of glycerol demonstrated that growth and product formation are very sensitive to changes of substrate concentration in the culture. This sensitivity is due to the dynamic responses of the genetic and metabolic networks. They should be considered when modeling the dynamics of the culture and attempting to improve the formation of 1,3-PD. © 1998 John Wiley & Sons, Inc. Biotechnol Bioeng 59: 544-552, 1998.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim [u.a.] : Wiley-Blackwell
    Materials and Corrosion/Werkstoffe und Korrosion 46 (1995), S. 39-41 
    ISSN: 0947-5117
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Cracking of fine-grained structural steels related to hot-dip galvanizing
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim [u.a.] : Wiley-Blackwell
    Materials and Corrosion/Werkstoffe und Korrosion 47 (1996), S. 42-45 
    ISSN: 0947-5117
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Fractures of prestressing steels caused by contact to zinc
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 74 (1962), S. 839-847 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die bisher nicht bekannten tricyclischen Ringsysteme des Pyrazolo[1,5-a]benzimidazols und des Pyrazolo[5,1-b]chinazolons konnten nach verschiedenen Methoden hergestellt werden. Das bereits bekannte Pyrazolo[3,4-b]chinolin ließ sich nach einem neuen, wesentlich einfacheren Verfahren synthetisieren. Die genannten Verbindungen wurden in ihre Alkyl-, Sulfo-, Nitroso-, Nitro-, Amino- und Azo-Derivate übergeführt und als Komponenten für Farbfilme erprobt.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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